ARMY MODEL UH-1H/V HELICOPTERS. OPERATOR’S MANUAL (1988)

TM 55-1520-210-10

CAUTION PANEL

FAULT

WORDING

CONDITION

ENGINE OIL PRESS

Engine oil pressure below 25 psi

*ENGINE ICING

Engine Icing detected

*ENGINE ICE DET

Not connected

ENGINE CHIP DET

Metal particle in engine oil

LEFT FUEL BOOST

Left fuel boost pump inoperative

RIGHT FUEL BOOST

Right fuel boot pump inoperative

ENG FUEL PUMP

Engine fuel pump inoperative

20 MINUTE

Fuel quantity bout 170 Ibs

FUEL FILTER

Fuel filter Impending bypass

*GOV EMER

Governor switch m emergency position

AUX FUEL LOW

Auxiliary fuel tank empty

XMSN OIL PRESS

Transmission oil pressure below 30 psi

XMSN OIL HOT

Transmission oil temperature above 110°C

HYD PRESSURE

Hydraulic pressure Low

*ENGINE INLET AIR

Engine air filter clogged

INST INVERTER

Failure of inverter

DC GENERATOR

DC Generator failure

EXTERNAL POWER

External power access door open

CHIP DETECTOR

Metal particles present in 42’ or 90’ gearbox

or main- transmission

*IFF

IFF System inoperative

*May not be installed on all configu

ration

Figure 2-9. Caution Panel - Typical

Change 17

2-35

55-1520-210-10

Chapter 3

Avionics

Section I.

GENERAL

3-1.

General This chapter covers the avionics

of the trigger switch is used for keying the inter-

equipment

configuration.

includes a brief

phone. The fully depressed (second detent) position

description of the avionics equipment, its technical

of the trigger switch keys the radio selected with the

characteristics,

capabilities,

and location. The

transmit-interphone selector switch on the signal

chapter

also

contains

complete

operating

distribution panel. A foot-operated type keying

instructions for all avionics equipment installed. For

switch (pilot and copilot) is located at each side of

mission avionics equipment, refer to chapter

the center console, between the center console and

Mission Equipment.

cyclic control stick, and on the cabin floor at each

crew station. The depressed position of the foot-op-

3-2.

Avionics Equipment Configuration

The

erated switch keys the radio or interphone selected

configuration consists of the following:

with the rotary selector switch at the appropriate sig-

nal distribution panel.

a. Headset Cordage. The pilot and copilot cordage

connectors are located at their respective sides

c. Power Supply and Circuit Breakers. Refer to fig-

near the aft portion of the overhead console. The

ure

2-8.

crew cordage connectors are located near the over-

head mounted signal distribution panel (figs

3-1,

d. Operation. The operation of the avionics equip-

3-2, and 3-3) at each crew station.

ment in this helicopter is dependent on the operation

of the interphone system (figs 3-1, 3-2, and 3-3).

b. Keying Switches. A trigger type keying switch is

Do not turn interphone system off until the end of

located on each (pilot and copilot) cyclic control

flight day.

stick grip. The half depressed (first detent) position

Section Il. COMMUNICATIONS

3-3. Signal Distribution Panel-SB-329/AR

(2)

RECEIVERS switches-As desired.

a. Description. The Signal Distribution Panel, lo-

(3)

TRANS selector switch-As desired.

cated at each crewmember station, amplifies and

(4)

VOL control-Adjust.

controls the distribution of audio signals between

each headset-microphone, to and from radio trans-

3-4. Signal Distribution Panel C-1611/AIC

mitters and receivers, and from navigation receiv-

ers. The system is used for intercommunications be-

a. Description. The Signal Distribution Panel ampli-

tween crewmembers and for monitoring communi-

fies and controls the distribution of audio signals ap-

cation and navigation receivers singly or in combina-

plied to or from each headset-microphone, to or

tion.

from communication receivers and transmitters,

from navigation receivers, intercommunication be-

b. Controls and

Functions. Refer to figure 3-1.

tween crewmembers, and for monitoring the com-

munication and navigation receivers singly or in

C. Operation.

combination. In addition the C-1611/AIC panel per-

(1) FM Switch

panel AN/ARC-44 number 31CS

mits the operator to control four receiver-transmit-

ters. A private interphone line is also provided.

switch-up.

3-1

TM 55-1520-210-10

CONTROL/lNDICATOR

FUNCTION

Receive switches

The switches marked

3 MB and NAV are for connecting or

disconnecting receiver audio signals to the associated headset. The up

position is on and connects the receiver. The down position is off and

disconnects the receiver. The number 1 switch is for the FM receiver,

number 2 switch is for the UHF receiver and switch number 3 is for the

VHF receiver when installed. The switch marked MB connects audio

from the marker beacon receiver, and the switch marked NAV

connects audio from the ADF or VHF navigation receivers.

TRANS selector switch

This is a rotary type switch with indicator window at the top. The

switch has four positions, INT, 1 (FM), 2 (UHF), and 3 (VHF). Positions

2, and 3 select the receiver-transmitter to be used to receive or

transmit regardless of the position of the RECEIVERS

3 switches.

The INT position connects signal distribution panels for interphone

operation. The operator will hear side tone when transmitting. The

other crewmember will hear the interphone message regardless of the

position of their TRANS selector switch.

VOL control

Adjusts the volume level of the audio applied to the headset associated

with the INT signal distribution panel.

Figure 3-1. Signal Distribution Panel SB-329/AR

3-2

Change

TM 55-1520-210-10

CONTROL/lNDICATOR

FUNCTION

1. Receiver Switches

Connect (ON) or disconnect OFF)

communications receivers from the headsets.

1 - FM No.

1 ARC-54 or ARC-131

2 - UHF ARC-51BX

- VHF ARC-115

- HF ARC-102

- FM No. 2 ARC-114

2. AUX Receiver Switch

Connects (ON) or disconnects (OFF) VOR omni

receiver ARN-82 from the headset.

3. NAV Receiver Switch

Connects (ON) or disconnects (OFF) ADF

navigation receiver ARN-83 from the headset.

4. HOT MIKE Switch

Permits hand-free intercommunications with

transmit-interphone selector in any position.

6. VOL Control

Adjusts volume from receivers.

Adjusts intercommunications volume.

6. Transmit- Interphone Selector

Selects transmitter to be keyed and connects

microphone to transmitters.

1 - FM No.

1 ARC-54 or ARC-131

- UHF ARC-51BX

- VHF ARC-115

- HF ARC-102

6 - FM No. 2 ARC-114

ICS

Connects the microphone to the

intercommunications system only, disconnecting

microphone from transmitters.

Figure 3-3. Signal Distribution Control Panel (C-6533/ARC)

3-4

Change 7

TM 55-1520-210-10

When the selector switch is in the PVT position it

tal, tunes in 0.05 MHz increments and provides 3500

provides a hot line (no external switch is used) to

channels. The set also permits 20 preset channels

any station in the helicopter which also has PVT se-

and monitoring of the guard channel. Transmission

lected. A HOT MIC switch is also provide on the

and reception are conducted on the same fre-

C-1611/AIC control panel at the medical attendants

quency.

station. Four C-1611/AIC units may be installed in

b. Controls and Functions. Refer to figure 3-4.

serial no. 63-8739 and subsequent. One each of the

units are installed for the pilot and copilot, and two

c. Operation.

are installed in the crew/passenger compartment of

the crew. All four of the C-1611/AIC units are wired

(1)

UHF function select switch-T/R (T/R+G as de-

to provide interphone operations for the crew, and

sired)

full transmit and receive facilities for all communica-

tion and navigation equipment.

(2)

UHF mode selector switch-PRESET CHAN.

b. Controls and Functions. Refer to figure 3-2.

(3)

RECEIVERS switch No. 2-ON

c. Operation.

(4) Channel-Select.

(1)

Transmit interphone selector switch-As de-

NOTE

sired.

An 800-cps audio tone should be heard

(2)

RECEIVERS switches-As desired.

during channel changing cycle.

(3)

Microphone switches-As desired.

(5) SQ DISABLE switch-OFF.

(4)

VOL control-Adjust.

(6) VOL-Adjust.

3-5.

Signal Distribution Panel C-6533/ARC

(7) Transmit-interphone selector switch-No.

position.

a. Description. Two panels are installed in the

pedestal for the pilot and copilot and two panels are

d. Emergency Operation.

installed in the cabin roof aft of the overhead con-

(1) UHF mode switch-GD XMIT.

sole for the right and left crewmembers. The system

is used for intercommunications and radio control.

(2) UHF function switch-T/R+G.

The system has three modes of operation; two way

radio communications, radio monitoring, and inter-

3-7. UHF Radio Set AN/ARC-51X

phone.

a. Description. The radio set provides two way

b. Controls and Functions. Refer to figure 3-3.

communications in the UHF (225.0 to 399.9 MHz)

band. The set located at the left side of the pedes-

c. Operation.

tal, tunes in 0.1 MHz increments and provides 1750

(1)

NAV receiver switch-As desired.

channels. The set also permits monitoring of the

guard channel. Transmission and reception are con-

(2)

AUX receiver switch-As desired.

ducted on the same frequency.

(3)

Transmit-interphone selector switch-As de-

b. Controls and Functions. Refer to figure 3-5.

sired.

c. Operation.

(4)

Receiver switches-As desired.

(1) UHF function selector switch-T/R (T/R+G as

(5)

HOT MIKE switch-As desired.

desired). Allow five minute warmup.

(6)

VOL control-Adjust.

(2)

Frequency-Select.

3-6. UHF Radio Set AN/ARC-51BX

(3)

RECEIVERS switch No. 2-ON.

a. Description. The Radio Set provides two way

(4) SENS and VOL controls-Adjust.

communications in the UHF (225.0 to 399.9 MHz)

band. The set located at the left side of the pedes-

Change 7

3-5

TM 55-1520-210-10

1. Mode selector

2. Preset channel control

3. Function select switch

0.05 megahertz control

1 megahertz control

10 megahertz control

CONTROL/lNDICATOR

FUNCTION

Function select switch

Applies power to radio set and selects type of operation as follows:

OFF position - Removes operating power from the set.

T/R position - Transmitter and main receiver ON.

T/R + G position - Transmitter, main receiver and guard receiver ON.

ADF position - Energizes, UHF-DF system when installed.

VOL control

Controls the receiver audio volume.

SQ DISABLE switch

In the ON position squelch is disabled. In the OFF position, the squelch

is operative.

Mode Selector

Determines the manner in which the frequencies are selected as

follows:

PRESET CHAN position - Permits selection of one of

20 preset

channels by means of preset channel control.

MAN position - Permits frequency selection by means of megacycle

controls.

(GD XMIT position - Receiver-transmitter automatically tunes to

guard channel frequency

(243.00 MHz).

PRESET CHANnel

Permits selection of any one of

20 preset channels.

Preset channel indicator

Indicates the preset channel selected by the preset channel control.

Ten megahertz control

Selects the first two digits (or ten-megahertz number).

One megahertz control

Selects the third digit (or one-megahertz number).

Five-hundredths

Selects the fourth and fifth digits (or

0.05 megahertz number).

megahertz control

Figure

3-4. UHF Control Panel C-6287/ARC-51BX

3-6

Change 7

TM 55-1520-210-10

1. Frequency selector (first two digits)

2. Frequency selector (third digit)

3. Frequency selector (fourth digit)

4. Function selector switch

CONTROL/lNDICATOR

FUNCTION

Function select

Applies power to the radio and selects type of operation as follows:

switch

OFF position - Removes operating power from radio set.

T/R position - Applies power to the set and permits transmission and

reception; guard receiver is not operative.

T/R

+ G position

- Permits transmission and reception; guard

receiver is operative.

ADF position - Not used.

VOL control

Controls the receiver audio volume.

SENS control

Adjusts main receiver sensitivity. When rotated fully clockwise the

control disables the squelch.

Ten-megahertz

Selects the first two digits (or ten-megahertz number}.

control

One-megahertz

selects the third digit (or one-megahertz number).

control

One-tenth

Selects the fourth digit (or tenth-megahertz number).

megahertz control

Figure

3-5. UHF Control Panel C-4677/ARC-51X

Change 7

3-7

TM 55-1520-210-10

1. Function selector switch

2. Frequency selector (first two digits)

3. Frequency selector (third digit)

4. Frequency selector (fourth digit)

CONTROL/lNDICATOR

FUNCTION

Selector switch

Applies power to the radio set and selects the mode of operation

OFF position - turns off primary power.

T/R position - transmitter and main receiver are on.

T/R + G REC position - transmitter, main receiver and guard

receiver are on.

ADF position - not used.

Volume sensitivity

This is a dual purpose rotary control. The larger or outer knob is

control

marked SENS, and controls receiver sensitivity. The smaller or inner

knob is marked VOL, and controls receiver volume.

Tuning controls

The tuning controls consist of two large control knobs, an inner control

knob, and an indicator window. The large knob on the left side selects

the first two digits (or ten megahertz number). The large knob on the

right side selects the third digit (or one megahertz number). The inner

knob selects the fractional (or tenth megahertz number).

Figure

3-6. UHF Control Panel C-1827/ARC-55B

3-8 Change 7

55-1520-210-10

(5) Transmit-interphone

selector switch-No.

d. Emergency Operation. Select guard frequency

position.

121.50 MHz.

d. Emergency Operation. Select guard frequency

3-10. VHF Radio Set-AN/ARC-134

243.0 MHz.

a. Description. The set transmits and receives the

3-8. UHF Radio Set AN/ARC-55B

same frequency. The panel (VHF COMM) is located

on the left side of the pedestal. The set provides

a. Description. The UHF command set provides

voice communications in the VHF range of 116.000

two way, amplitude-modulated communications on

through 149.975 MHz on 1360 channels spaced 25

any of 1750 channels within 225.0 to 399.9 MHz.

kHz apart.

Channel selection is manual and the guard channel

may be monitored.

b. Controls and Functions Refer to figure 3-8.

b. Controls and Functions. Refer to figure 3-6.

c. Operation.

(1)

OFF/PWR switch-PWR. Allow set to warm up.

(1) UHF function selector switch-As desired.

(2)

Frequency-Select.

(2) Frequency-Select.

(3)

RECEIVERS switch No. 3-ON.

(3) RECEIVERS switch No. 2-ON.

(4)

Volume-Adjust. If signal is not audible with

VOL control fully clockwise, press COMM TEST

(4) UHF VOL-SENS controls-Adjust.

switch to unsquelch circuits.

(5) Transmit-interphone selector switch-No.

position.

d. Emergency Operation. Select guard frequency

(6) OFF/PWR switch-OFF.

243.0 MHz.

d. Emergency Operation. Select guard frequency

3-9. VHF Radio Set AN/ARC-115

121.500 MHz.

a. Description. The VHF Radio Set provides ampli-

3-11. VHF Radio Set-AN/ARC-73

tude-modulated, narrow band voice communica-

tions within the frequency range of 116.000 to

a. Description. The VHF Command Set is an alter-

149.975 MHz on 1360 channels for a distance of ap-

nate set for the UHF radio. The set provides trans-

proximately 50 miles line of sight. A guard receiver

mission and reception of AM radio signals in the VHF

is incorporated and fixed tuned to 121.50 MHz. The

range. The receiver may be tuned within its fre-

panel is Iabeled VHF AM COMM and mounted on the

quency range of 116.00 to 151.95 MHz in 50 kHz

left side of the pedestal.

increments to any of the 720 available channels. The

transmitter may be tuned within its frequency range

b. Controls and Functions. Refer to figure 3-7.

of 116.00 to 149.95 MHz in 50 kHz increments to any

c. Operation.

one of its

680 available channels. The distance

range is limited to line of sight or a distance of ap-

(1)

Function selector-As desired.

proximately 50 miles.

(2)

Frequency-Select.

b. Controls and Functions. Refer to figure 3-9.

(3)

RCVR TEST-Press to test.

c. Operation.

(4)

AUDIO-Adjust.

(1)

POWER switch-ON.

(5) Transmit-interphone selector switch-No.

(2)

Frequency-Select.

position.

(3) RECEIVERS switch No. 3-ON.

(6) RADIO transmit switch-Press.

Change 7

3-9

TM 55-1520-210-10

(4) SQ and VOL controls - Adjust.

3-13.

FM Radio Set - AN/ARC-131.

(5) Transmit interphone selector switch

No.

a. Description The FM Radio Set consists of a

3position.

receiver-transmitter,

remote control panel unit;

d. Emergency Operation Select guard

communication antenna and a homing antenna The

frequency121.500 MHz.

radio set provides 920 channels spaced 50 kHz apart

within the frequency range of 30.00 to 75.95 MHz.

3-12.

FM Radio Set - AN/ARC-114 and -114A.

Circuits are included to provide transmission sidetone

a Description The FM Radio Set provides two

monitoring. The control panel is located on the pedestal.

way frequency modulated (FM) narrow band voice

Homing data is displayed by the course indicator (fig 3-

communications and homing capability within the

20) on the instrument panel. A channel changing tone

frequency range of 30.00 to 75.95 MHz on 920 channels

should be heard in the headset while radio set is tuning.

for a distance range limited to line of sight. A guard

When the tone stops, the radio set is tuned. Operation in

receiver is incorporated in the set and is fixed tuned to

DIS position is possible; however flags on course

40.50 MHz. It has the additional capability -for

deviation indicator will be inoperative. When the first FM

retransmission of voice, or X-mode communications in

radio set is m the homing mode, the homing indicator

conjunction with radio set AN/ARC-131. The radio set is

may deflect left or right of on course indication while the

marked VHF FM COMM and is mounted on the center

second FM radio set Is keyed.

console, on helicopter serial Nos.

71-20000 and

b. Controls and Functions. Refer to figure 3-1 1.

subsequent.

c. Operation Depending on the settings of the

Controls and Functions. Refer to figure 3-10.

control panel controls, the radio set can be used for the

Operation.

following types of operation: Two way voice

(1) Two Way Voice Communication.

communication and homing (fig 3-12).

(a) Function selector - As desired.

(1) Two Way Voice Communication.

(b) Frequency - Select.

(a) Mode control switch - T/R (allow two minute

warm up).

(d) AUDIO - Adjust.

(b) Frequency - Select.

(e) Transmit interphone selector

- No.

position.

(d) VOL control - Adjust.

(2) Retransmission.

(e) SQUELCH control - Set for desired

squelch mode.

NOTE

(f) TRANS selector switch - No. I.

For transmission both FM circuit breakers must be in.

(2) Homing Operation.

(a) Frequencies - Select (both FM sets). -

(a) Mode control switch - HOME.

(b) Communications

- Establish with each

(b) Frequency - Adjust to frequency of selected

facility by selecting number I position and then number 5

homing station

position on the transmit-interphone selector.

TONE, however, the carrier squelch is automatically

sets).

selected by an internal contact arrangement on HOME

(d) Receivers switches - Number I and number

position.

5 positions as desired for monitoring.

(d) Fly helicopter toward the homing station by

d. Emergency Operation. Select guard frequency

heading in direction that causes homing course deviation

40.50 MHz.

indicator right-left vertical pointer to position itself m the

center of indicator scale. To ensure that helicopter is not

heading away from the homing station, change the

heading slightly and note that the course deviation

indicator vertical pointer deflects in direction opposite

that of the turn.

3-12

Change 17

(3) Retransmit Operation. Start the equipment and

proceed as follows for retransmit operation:

(3) Retransmit Operation. Start the equipment and

(a) Mode controls (both control units)

perform the following for retransmit operation.

RETRAN.

(a) Mode controls (both control units)

(b) SQUELCH controls (both control units) -

RETRAN.

Set as required. Do not attempt retransmit operation

(b) SQUELCH controls (both control units) -

with SQUELCH controls set to DIS. Both controls must

Set as desired.

be set to CARR or TONE. To operate satisfactorily the

NOTE

two radio sets must be tuned to frequencies at least 3

Do not attempt retransmit operation with the

MHz apart.

SQUELCH controls set to DIS. Both controls

must be set to CARR or TONE.

desired operation.

(4) Stopping Procedure. Mode control switch -

OFF.

desired operation. To operate satisfactorily the two radio

3-14. FM Radio Set AN/ARC-54.

sets must be tuned to frequencies at least 5 MHz apart.

a. Description The FM Radio Set provides two-

(4) Stopping Procedure. FM mode selector switch

way communications within the frequency range of 30.00

-OFF.

to 69.95 MHz. Voice communication permits selective

calling (TONE) and when used with the homing antenna

3-15.

FM Radio Set AN/ARC-44

and course indicator the pilot is provided with a homing

a. Description. The FM Radio Set provides two

facility. A channel changing tone should be heard in the

way communications within the frequency range of 24.0

headset while radio set is tuning. When the tone stops

to 51.9 MHz on 280 preset channels. Signal distribution

the radio set is tuned. Voice reception is possible m

panel SB-329 and control panel assembly 204-075-219

HOME position. With two or more FM radio sets

(FM switch assembly), to provide squelch control and

installed and the first FM radio set is in the homing

power to the antenna group are used in conjunction with

mode, the homing indicator may deflect left or right of on-

the FM Liaison Radio Set (fig 3-2 and fig 3-14). The set

course indication while the second FM radio set is keyed.

provides a homing facility on signals between 24.0 and

b. Controls and Functions. Refer to figure 3-12.

49.0 MHz. Cycling may take place in the receiver

C Operation.

transmitter. This will be indicated by a 400-cycle-per-

(1) Two Way Voice.

second signal heard in the headset

(a) FM mode selector switch - PTT (allow three

b. Controls end Functions. Refer to figure 3-13.

minute warm-up).

c. Operation

(b) Frequency - Select.

(1) Preliminary Setup.

(a) FM power switch - ON.

(d) FM SQUELCH control - CARR (or as

(b) FM home switch - Down.

desired).

No. 1 position.

(e) RECEIVERS switch No. 1 -- ON.

(d) REM-LOCAL switch -

LOCAL.

(f) TRANS selector switch - No. 1.

(e) Frequency - Select.

(g) Microphone switch - Press.

(2) Standing Procedures.

(2) Homing Operation. FM mode selector switch -

(a) BAT switch - ON (OFF for APU).

HOME.

(b) INT and FM circuit breakers - In.

Change 17

3-12.1

TM 55-1520-210-10

up).

(1) Preliminary

(3) Interphone Operation.

(a) Set the control indicator POWER switch to

(a) Microphone switch - Press.

ON.

(b) Speak into the microphone

- Adjust

(b) Apply power to FM radio set.

interphone volume.

(4) FM Receive-Transmit Operation.

alarm procedure is initiated.

(a) ICS switch - Up.

1. A constant tone is heard in the headset and

(b) FM ON-OFF power switch - ON.

after approximately two seconds the constant tone will

change to an interrupted tone.

(d) TRANS selector switch - No. I position.

2. To clear the interrupted tone press and

(e) Microphone switch - Press to transmit.

release the press to talk switch the interrupted tone will

(5) FM Home Operation. FM HOME switch - Up.

Stopping Procedures.

longer be heard and the circuit will be in a standby

(a) FM HOME switch - Down.

condition ready for either transmission or reception. No

(b) FM POWER switch - OFF.

traffic will be passed if the interrupted tone is still heard

after pressing and releasing the press to talk switch. (d)

Set control unit function switch for desired type of

3-16.

Voice Security Equipment - TSEC/ KY-28.

operation (2 and 3 below).

a. Description. The Voice Security Equipment is

(2) Plain Mode.

used with the FM Command Radio to provide secure two

(a) Set the control indicator POWER switch to

way communication (figs

3-11 through

3-14). The

ON.

equipment is controlled by the control-indicator mounted

(b) Set the PLAIN-CIPHER switch to PLAIN

in the pilot

(indicated by red light).

right console. The POWER switch must be in the ON

position regardless of the mode of operation whenever

when operating with retransmission units, at which time-

the equipment is installed.

switch will be placed in the RE-X position.

b. Control and Functions. Refer to figure 3-14.

(d) Press the press to talk switch and speak

c. Operation. Normal operation will exist without

into the microphone to transmit. Release the press to

its

talk switch for reception.

encoder/decoder and control indication being installed in

(3) Cipher Mode.

the helicopter. However two operation modes are

(a) Set the PLAIN-CIPHER switch to CIPHER

available when they are installed. PLAIN mode for

(indicated by a green light).

enciphered radio transmission or reception and CIPHER

(b) Place the RE-X-REG switch to REG except

mode for ciphered radio transmission or reception. Both

when operating with retransmission units at which time

modes may be operated with or without retransmission

the switch will be placed in RE-X position. (c) To transmit

nits.

press the press to talk switch. DO NOT TALK; in

approximately one-half second a be

will be heard. This indicates the receiving station is now

capable of receiving your message. Transmission can

now

commence. Only one voice security system can transmit

on a given frequency. Always listen before attempting to

transmit to assure that no one else is transmitting.

Change 17 3-12.2

TM 55-1520-210-10

CONTROL/lNDICATOR

FUNCTION

Function Selector

OFF

Power Off

T/R

Receiver - On; Transmitter - Standby.

T/R GUARD

Receiver - On; Transmitter - Standby; Guard Receiver - On.

NOTE

Reception on guard frequency is unaffected by

frequencies selected for normal communications.

HOMING

Not Used.

RETRAN

Activates the Retransmission Mode in Conjunction with Radio

Set ARC-54 or ARC-131.

2. Frequency selectors

Left Selector

Selects first two digits of desired frequency

Right Selector

Selects third and fourth digits of desired frequency.

3. RCVR TEST

When pressed audible signal indicates proper receiver

performance.

4. AUDIO

Adjusts receiver volume.

5. SQUELCH (ARC

114)

Squelch control adjusted by maintenance personnel only.

6. SQUELCH (ARC

114A)

OFF

Disables squelch.

NOISE

Enables noise squelch.

TONE X

Enables tone squelch and Secure Voice operation.

Figure

3-10. Control Panel AN/ARC-114 and AN/ARC-114A

3-14

Change 7

TM 55-1520-210-10

1. Tens megahertz digit

frequency selector

2. Frequency indicators

3. Units megahertz digit

frequency selector

4. Tenths magahertz digit

frequency selector

5. Frequency indicators

6. Hundredths megahertz digit

frequency selector

7. Mode control switch

CONTROL/lNDICATOR

FUNCTION

Mode control switch

(four-position switch)

OFF

Turns off primary power.

T/R

Radio set operates in normal communication mode (reception).

(transmit/receive)

(Aircraft transmit switch must be depressed to transmit.)

RETRAN

Radio set operates as a two-way relay station.

(retransmit)

(Two radio sets are required set at least 3 MHz apart.)

HOME

Radio set operates as a homing facility.

(Requires a homing antenna and indicator.)

VOL control

Adjusts the audio output level of the radio set.

SQUELCH switch

(three-position

rotary switch)

DIS (disable)

Squelch circuits are disabled.

CARR (carrier)

Squelch circuits operate normally in presence of any carrier.

TONE

Squelch opens (unsquelches) only on selected signals

(signals containing a

150-cps tone modulation).

Frequency indicator

Tens megahertz

Selects the tens megahertz digit of the operating frequency.

frequency selector

Units megahertz

Selects the units megahertz digit of the operating frequency.

frequency selector

Tenths megahertz

Selects the tenths megahertz digit of the operating frequency.

frequency selector

Hundredths megahertz

Selects the hundredths megahertz digit of the operating

frequency selector

frequency.

Frequency indicator

Displays the operating frequency of the radio set.

Figure 3-11. FM Radio Set Control Panel AN/ARC-131

Change 7

3-15

TM 55-1520-210-10

1. Frequency control whole

- megahertz

2. Mode selector switch

3. Frequency control decimal

- megahertz

CONTROL/lNDICATOR

FUNCTION

Mode selector

Applies power to the set and selects the mode of operation.

switch

OFF position - Turns off primary power. PTT (push-to-talk) applies

power. Radio set operates in normal communication mode. (Radio

cyclic stick switch or foot switch must be pressed to transmit.)

RETRAN (retransmit) - Applies power. Radio set operates as a

two-way relay station. (Two radio sets are required set at least

5 MHz apart)

HOME position - Applies power and radio set operates with

637A-2.

Homing Antenna and Course indicator as a homing facility.

Voice capability is provided in all three operating positions.

VOL control

Controls the receiver audio volume.

SQUELCH control

Selects one of three squelch modes as follows:

DIS (disable) position - Squelch circuits are disabled.

CAR (carrier) position - Squelch circuits operate normally.

TONE position - Squelch opens (unsquelches) only on signals

containing a

150-cps tone modulation.

Frequency control

Selects the whole megahertz digits

whole-megahertz digit

Frequency control

Selects the decimal-megahertz digits.

decimal-megahertz digit

Megahertz display

Displays the selected operating frequency.

window

Figure 3-12. FM Radio Set Control Panel C-3835/ARC-54

3-16

Change 7

TM 55-1520-210-10

(d) When transmission is completed, release

the

NOTE

press to talk switch. This will return equipment to

the

standby condition.

When operating in either secure or clear

(e) To receive, it is necessary for another station

(plain) voice operations the VOLUME must

to send you a signal first. Upon receipt of a signal

be adjusted on the aircraft radio and

the cipher equipment will be switched automatically

intercom equipment to a comfortable

to the receive condition, which will be indicated by a

operating level.

short beep heard in the headset. Reception will then

be possible. Upon loss of the signal, the cipher

(2) Clear Voice Procedures:

equipment will be automatically returned to the

(a) To operate in clear voice (plain text) simply:

standby condition.

1 Set the Z-AHP(RCU) PLAIN-C/RAD switch to

3-16.1 Voice Security Equipment TSEC/KY-58

PLAIN.

a. Description. The voice security equipment is

2 Operate the equipment

used with the FM Command Radio to provide secure

two way communication. The equipment is con-

(3) Zeroing Procedures

trolled by the control-indicator (Z-AHP) mounted in

the right pedestal panel. The POWER switch must be

in the ON position, regardless of the mode of opera-

NOTE

tion, whenever the equipment is installed.

Instructions should originate from the Net

b. Controls and Functions.

Refer to Figure 3-14.

Controller or Commander as to when to

zeroize the equipment

c. Operating Procedures.

(a) To zeroize the KY-58: (Power must be on).

(1) Operating procedures for secure voice.

1 Lift the red ZEROIZE switch cover on the RCU.

2 Lift the spring-loaded ZEROIZE switch. This will

zeroize positions

1-6.

To talk in secure

voice, the KY-58 must be

“Loading” with

any number of desired

3 Close the red cover.

variables.

The equipment is now zeroized and secure voice

(a) Set to MODE switch to OP.

communications are no longer possible.

(b) Set the FILL switch to the storage register

(4) Automatic Remote Keying Procedures

which contains the crypto-net variable (CNV) you

desire.

NOTE

Automatic Remote Keying (AK) causes an

(d) Set the PLAIN C/RAD switch to C/RAD.

"old" crypto-net variable (CNV) to be

replaced by a “new” CNV. Net Controller

(e) If the signal is to be retransmitted, set the DE-

simply transmits the “new” CNV to your

LAY switch to (ON).

KY-58.

(f) At this time a crypto alarm, and backg0round

(a) The Net Controller will use a secure voice

noise, in the aircraft audio intercom system should

channel, with directions to stand by for an AK trans-

be heard. To clear this alarm, press and release PTT

mission. Calls should not be made during this

in the aircraft audio/intercom system. Secure voice

standby action.

communication is now possible.

3-20

Change 7

TM 55-1520-210-10

(b) Several beeps should now be heard in your

(6) It is important to be familiar with certain KY-58

headset. This means that the "old" CNV is being

audio tones. Some tones indicate normal operation,

replaced by a "new" CNV.

while other indicate equipment malfunction. These

tones are:

ask you for a “radio check.”

(a) Continuous beeping, with backg0round noise,

is cryptoalarm. This occurs when power is first ap-

(d) After the “radio check” is completed, the Net

plied to the KY-58, or when the KY-58 is zeroized.

Controller instructions will be to resume normal

This beeping is part of normal KY-58 operation. To

communications. No action should be taken until the

clear this tone, press and release the PTT button on

net controller requests a “radio check.”

the Z-AHQ (after the Z-AHQ LOCAL switch has

been pressed. Also the PTT can be pressed in the

(5) Manual Remote Keying Procedures.

cockpit.

(a) The Net Controller will make contact on a se-

(b) Background noise indicates that the KY-58 is

cure voice channel with instructions to stand by for a

working properly. This noise should occur at TURN

new crypto-net variable (CNV) by a Manual Remote

ON of the KY-58, and also when the KY-58 is gener-

Keying (MK) action. Upon instructions from the Net

ating a cryptovariable. If the backg0round noise is not

Controller:

heard at TURN ON, the equipment must be checked

out by maintenance personnel,

1 Set the Z-AHP FILL switch to position 6. Notify

the Net Controller by radio, and stand by.

alarm.” This will occur whenever an empty storage

2 When notified by the Net Controller, set the Z-

AHP MODE switch to RV (receive variable). Notify

This tone can mean any of three conditions:

the Net Controller, and stand by.

1 Selection of any empty storage register.

3 When notified by the Net Controller, set the Z-

AHP FILL switch to any storage position selected to

2 A “bad” cryptovariable is present.

receive the new CNV (May be unused or may con-

tain the variable being replaced). Notify the Net Con-

3 Equipment failure has occurred. To clear this

troller, and stand by.

tone, follow the “Loading Procedures” in TM

11-5810-262-OP. If this tone continues, have the

NOTE

equipment checked out by maintenance personnel.

When performing Step

3, the storage

(d) Continuous tone could also indicate a cryp-

position (1 through 6) selected to receive

toalarm. If this tone occurs at any time other than in

the new CNV may be unused, or it may

contain the variable which is being

clear this tone, repeat the “Loading Procedures” in

replaced.

TM 11-5810-262-OP. If this tone continues, have

the equipment checked out by maintenance person-

(b) Upon instructions from the Net Controller:

nel.

Listen for a beep on your headset.

(e) Single beep, when RCU is not in TD (Time De-

lay), can indicate any of three normal conditions:

Wait two seconds

1 Each time the PTT button is pressed when the

Set the the RCU MDOE switch to OP

KY-58 is in C (cipher) and a filled storage register is

Confirm

selected, this tone will be heard. Normal use

(speaking) of the KY-58 is possible.

Controller will now contact you via the new CNV.

2 When the KY-58 has successfully received a

cryptovariable, this tone indicates that a “good”

(d) If the MK operation was not successful, the

cryptovariable is present in the selected register.

Net Controller will contact you via clear voice (plain)

transmission; with instructions to set your Z-AHP

3 When you begin to receive a ciphered mes-

FILL selector switch to position 6, and stand by while

sage, this tone indicates that the cryptovariable has

the MK operation is repeated.

3-21

Change

TM 55-1520-210-10

(1) Function selector switch - As desired.

passed the “parity” check, and that it is a

good variable.

(2) Frequency controls - Desired frequency.

if the function selector is moved from the OFF po-

(f) A single beep, when the RCU is in TD

sition to an operating mode and the desired oper-

(Time Delay) occurring after the “preamble” is

ating frequency is already sat up on the control

sent, indicates that you may begin speaking.

panel, rotate the first selector knob one digit off

frequency and then back to the operating fre-

(g) A single beep, followed by a burst of

quency. This will allow the system to return to the

noise after which exists a seemingly “dead”

frequency.

condition indicates that your receiver is on a

different variable than the distant transmitter.

(3) RF-SENS-Adjust.

if this tone occurs when in cipher text mode:

Turn RCU FILL switch to the CNV and con-

(4) intercommunications HF switch-As de-

tact the transmitter in PLAIN text and agree

sired.

to meet on a particular variable.

d. Emergency Operation. The AN/ARC-102 HF

3-17. HF Radio Set AN/ARC-102

radio has two built-in protective devices that could

cause the set to stop operating. The condition and

a. Description. HF AM/SSB Radio Set

corrective steps are as follows:

AN/ARC-102 is a long range, high frequency

(hf), single side band (ssb), transceiver that

(1) A protective circuit is designed to turn

transmits and receives in the 2.0 to

30.0

the receiver-transmitter off, when a short exists in

MHz range. The control panel is located on

the output circuit. To restore the receiver-

the right side of the pedestal and tunes in one

transmitter to operation, move the function selec-

kHz stops to any of 28,000 manually se-

tor to OFF position and then back to the desired

lected frequencies. The primary mode of op-

operating mode:

eration is ssb. However, it can also transmit

end receive compatible amplitude modulated

(2) When the associated antenna coupler is

(am) signals.

required to complete several consecutive tuning

cycles it may become overheated. In this event a

b. Controls and Functions. Refer to figure

thermal relay in the coupler unit is designed to turn

3-15.

off the receiver-transmitter. If the receiver-

transmitter stops operating after a series of tuning

c. Operation.

cycles, position the function selector switch to

OFF position, allow the thermal relay to cool for

two minutes and return the function selector to

When ground testing ARC-102

the desired operating mode.

equipment, be sure that personnel

are clear of antenna. Serious bums

(3) if the above procedure does not return

can result if body contact is made

the HF radio set to normal operation, place the

with the antenna during ground

frequency selector to 29.000 MHz and function

testing.

selector in the “OFF” position. Report the failure to

the maintenance personnel.

3-22

Change 18

TM 55-1520-210-10

3-17.1 HF Radio Set AN/ARC-220 (MWO 1-1520-

may be transmitted or received in USB or LSB

modes. In addition to conventional HF communi-

210-50-33)

cation, the AN/ARC-220 provides automatic link

WARNING

establishment (ALE) and two types of electronic

counter countermeasures (ECCM) communica-

Make sure that no personnel are

tions. The ALE simplifies HF radio operation by

within 3 feet of the HF antenna when

automatically establishing a 2-way link on the

transmitting, performing radio checks

best available frequency.

or when in ALE mode. Do not touch

the RF output terminal on the antenna

The two types of ECCM communications (MIL-

coupler, the antenna lead-in wire, the

STD-188-141A ECCM and Army enhanced ECCM)

lnsulated feed trough, or the antenna

provide a frequency hopping technique that com-

itself while the microphone is keyed

bats the effects of communications jammer and

(after the tuning cycle is complete) or

direction finding attempts. Although two different

while the system is in transmit self-

types of ECCM are available, system operation is

test. Serious RF burns can result from

the same regardless of the type used.

direct contact with the above criteria.

The AN/ARC-220 also supports both standard and

WARNING

advanced narrow-band digital voice terminal

(ANDVT). Digital data interfaces compatible with

Tow aircraft outside of hanger or

MIL-STD-188-114A allow transmission and recep-

metal-covered building before per-

tion of data from improved data modem (IDM) and

forming power-on checks.

data secured by the AIRTERM (TSEC/KY-100). In

addition, the AN/ARC-220 includes a MIL-STD-

a. Description. The AN/ARC-220 is a high fre-

110A data modem which may, in noisy environ-

quency, single-side band radio set. It receives and

transmits on any one of

280,000 manually-

ments, allow data to be received when voice

selected frequency channels spaced at 100-Hz

communications cannot. Power to operate the

increments in the HF band (2.0 to 29.9999 MHz).

AN/ARC-220 is supplied from the 28 vdc essential

Preset channels can be manually programmed by

bus through the HF ARC-220 circuit breaker on

an operator or preprogrammed as part of the

the pilot overhead circuit breaker panel. A shorted

communications mission load information.

The

loop antenna is located on the rear left side of the

AN/ARC-220 provides secure and nonsecure voice

aircraft (figure 2-1. The length of the antenna is

and data communications. Voice communications

approximately 12.6 feet in length.

are possible using either simplex or half-duplex

operation in the upper sideband (USB), lower

b. Controls and Functions. Refer to figure 3-

sideband (LSB), amplitude modulation equivalent

14.1 and the following table.

(AME), and continuous wave (CW) modes. Data

Change 18

3-22.1

TM 55-1520-210-10

Figure 3-14.1. HF Radio Set AN/ARC-220 Control Panel C-12436/URC

Controls and Functions of Control Panel C-124361URC

CONTROL /INDICATOR

FUNCTION

Cursor switches

Four pushbutton switches that position cursor verti-

cally or horizontally on display (2).

Display

Liquid crystal display (LCD), consisting of six display

lines, for displaying advisory information. Depending

on operation, information that may be displayed on

each line is as follows:

Line 1

Alpha-numeric display of 15 characters maximum

containing channel title (call sign). Default value is

Mode: channel #.

Line 2

ALE Address

Alpha-numeric display of 15 characters maximum

containing Call To (ADRS: xxx) or Self (SELF:

xxx)Address. (ADRS:) and (SELF:) labels are re-

moved for addresses greater than 10 characters in

length.

Noise Reduction

Character display (ON, OFF) having display format of

NOISE REDUCE: xxx. Default value is ON.

3-22.2 Change

55-1520-210-10

Controls and Functions of Control Panel C-12436/URC (Cont)

CONTROL /INDICATOR

FUNCTION

Fill Type

Character display (KEY, DATA) having display format of

TYPE: xxxx x. Default is DATA.

Contention Control

Character display (ON, OFF) having display format of

LBC: xxx. Default is OFF.

Line 3

Receive Frequency

Numeric display (2.0 to 29-9999 MHz) with display for-

mat of RCV: xx.xxxxxxxx.

ECCM Station Type

Character display (MEMBER, ALTERNATE, MASTER, NET

ENTRY, ALT NET ENT). Default is MEMBER.

Lines 3,4

Character display of emission mode (USB, LSB, AME,CW)

one space to right of frequency. Default is USB.

Line 4

Transmit Frequency

Numeric display (2.0 to 29.9999 MHz) with display for-

mat of XMT: xx.xxxxxxxx.

Time

Numeric display (00:00:00 to

23:59:59) with display

format of Hour:Minute:Second.

Line 5

Link Protection

Character display (OFF, ON) with display format of LINK

PROT: xxx, Default is ON (OFF if no link protection data-

fill).

Date

Alphanumeric display (01 JAN 00 to 31 DEC 99) with

display format of dd MM yy.

Antenna Type

Character display (T/R, RCV) with display format of ANT:

xxx. Default is T/R.

Line 8

Power Level

Character display (LOW, MED, HIGH) with display format

of PWR: xxxx. Default is HIGH.

Squelch

Alpha-numeric display (TONE, 0 to 5) with display format

of - SQ: xxx.

Volume

Numeric display (1 to 8) with display format of VOL:x.

Listen Before Talk

Character display (ON, OFF) with display format of

LBT: xxx.. Default value is OFF.

Change 18

3-22.3

TM 55-1520-210-10

Controls and Functions of Control Panel C-12436/URC (Cont)

CONTROL/INDICATOR

FUNCTION

Line-select switches

Three pushbutton switches that select options dis-

played to left of each switch.

Brightness switches

Two pushbutton switches that varies display screen

brightness.

Channel/Net selector switch

Seven-position rotary switch that selects programmed

operating channels or nets, depending on operating

mode. The + position of switch allows additional

channel/net selections using VALUE switches

(12).

Data connector

Interfaces AN/ARC-220 system to data transfer device

for datafill.

Key connector

Interfaces AN/ARC-220 system to data transfer device

for keyfill.

Mode switch

Five-position rotary switch that selects following

modes of operation:

MAN

Permits single channel selection of operating fre-

quency and emission mode for conventional HF com-

munications.

PRE

Permits preprogrammed preset channel operation for

conventional HF communications.

ALE

Selects automatic link establishment mode of opera-

tion.

ECCM

Selects electronic counter-countermeasure mode of

operation.

EMER

Used during emergency situations to place a distress

call. The mode (manual, preset, ALE, or ECCM), fre-

quency, net, etc., is determined by the datafill.

-SQL + switches

Two pushbutton switches (left arrow) and (right ar-

row) that control radio squelch and audio muting.

10.

VOL switch

Eight position rotary switch that varies receive audio

output level.

3-22.4

Change 18

TM 55-1520-210-10

Controls and Functions of Control Panel C-12436/URC (Cont)

CONTROL /INDICATOR

FUNCTION

11.

Function switch

Five-position rotary switch that selects system operation

as follows:

OFF

Turns AN/ARC-220 system off.

STBY

Turns AN/ARC-220 system on and places system in-

standby. In standby, built-in-test (BIT), setup, or fill op-

erations can be performed to ready system for operation.

SILENT

Used in ALE or ALE-ECCM mode to preventAN/ARC-220

system from automatically responding to incoming calls,

T/R

Allows AN/ARC-220 system to transmit and receive in

selected mode of operation.

ZERO

Erases ail data (including datafill and keyfill) that has been

(PULL)

loaded into system. Switch must be pulled before setting

it to this position.

12.

Value

Two pushbutton switches that increment field value or

single character value, depending on cursor position.

Change 18

3-22.5

55-1520-210-10

c. Operating Modes/Functions.

(9) Output Power Level. Three output lev-

els are selectable for display screen by using EDIT

(1) Power ON/OFF. On Function Switch.

line-select switch, which brings up edit mode,

moving cursor under power character field and

(2) System Turn-On. Turning Function

using VALUE switches to change field. Depress

Switch clockwise from OFF to STBY turns system

RTN line-select switch which stores the change

on and selects standby function. SYSTEM

and returns to normal operating mode.

TESTING is displayed while power-up BIT (P-BIT)

is in process. SYSTEM-GO will be displayed if all

(10) Test. There are two Built-in-Test (BIT)

tests pass or SYSTEM-NO-GO if not.

features which concerns the operator, P-BIT and

C-BIT. The Power-Up Bit (P-Bit) tests the ARC-

(3) CRT Brightness.

Two pushbutton

220 when initially turned on. P-Bit exercises ba-

switches used to vary brightness. The

(up ar-

sic radio control functions which must be opera-

row) increases intensity while the

(down arrow)

tional prior to entering system operational mode.

decreases intensity.

A GO/NO-GO status appears on display and de-

faults to stand-by mode upon completion. When

(4) Audio Volume. Eight-position rotary

NO-GO status appears, depressing INOP line-

switch used to vary audio output level. Setting is

select switch displays INOP MODES so an opera-

displayed on line 6 (bottom) of display for 5 sec-

tor can see if limited capability exists. Continuous

onds when system is first turned on or when VOL

Bit (C-BIT) is automatically performed during sys-

setting is changed. Display levels are 1 through 8.

tem operation without any operator intervention.

Critical system functions are monitored. Any fail-

(5) Channel Selection. Channel number may

ures cause a NO-GO advisory, accompanied by

be changed using seven-position rotary chan-

portion of system which failed, to appear on line 5

nel/net selector switch. The + position of switch

of display. C-Bit failures are stored in nonvolatile

allows channels 7 or greater to be selected using

memory.

VALUE switches.

(11) Store. RTN line-select key, used to

(6) Modulation Mode. Four modes are avail-

terminate edit mode, automatically stores any

able: USB, LSB, AME, and CW. The modulation

change(s) made.

mode is determined by the data fill except for the

manual mode. Modulation mode can be changed

(12) Data Fill. Contains preset frequencies,

on manual channels

scan lists, addresses, data messages and ALE

and/or ECCM parameters. With system in STBY,

(7) Receive/Transmit Frequency.

2.0 to

press FILL line-select switch. From the FILL

29.9999 MHz, programmable in 100 Hz steps. To

screen, use the line select switch to select DATA.

change frequencies, depress EDIT line select

Connect data transfer device (DTD) of DATA con-

switch. While in Edit screen, use CURSOR to posi-

nector on radio set control front panel and initiate

tion cursor under appropriate frequency. Use

fill from DTD. LOADING is displayed during data-

VALUE switches to change frequency. (Note:

fill From the DATAFILL screen, use the line select

XMT frequency will automatically change with

switch to select LOAD. FILL ENABLED is dis-

RCV frequency, but the reverse is not true).

played during datafill. The AN/CYZ-10 DTD will

indicate when the datafiil is completed. Use the

(8) Squelch Level/Audio Muting (-SQL + ).

line-select switch to select RTN after the DTD

Two pushbutton switches

(left arrow) and

indicated datafill completed. The display will re-

(right arrow), when pressed, displays squelch

turn to the screen showing DATAFILL VERSION.

status on line 6 of display for 5 seconds. Settings

The approporated Datafill Version is displayed for

are TONE and 0 through 5. TONE provides no

a successful fill. A copy of loaded datafill can be

muting and no squelch. Position 0 provides mut-

sent to DTD by pressing COPY line-select switch.

ing but no squelch. Positions 1 through 5 provide

COPYING is displayed during operation, COPY

muting and increasing levels of squelch. Muting is

COMPLETE is displayed if successful, COPY FAIL

normally enabled during ALE operation.

copy

cannot

completed.

3-22.6 Change

TM 55-1520-210-10

Press RTN line-select switch to return to STBY

NOTE

screen when datafill is complete.

Disconnect

Pressing RTN line select key on

DTD.

DATA FILL page stops the fill proc-

ess.

(13) Key Fill. Loads secure keys. From the

FILL screen, use the line-select switch to select

KEY. Connect DTD to KEY connector on radio set

key - Press. FILL ENABLED screen will appear.

control front panel. From the KEYFILL screen, use

the line-select switch to select LOAD. Fill enabled

(d) Start data fill on DTD. Monitor DTD to

IS DISPLAYED DURING KEYFILL. Initiate keyfill

see when data transfer is complete.

from DTD. The AN/CYZ-10 DTD will indicate

when the keyfill is completed. Use the line-select

(3) Load Secure Keys. Key fill contains secure

switch to select RTN after the DTD indicates key-

information needed for ALE link protection and

fill is completed. The display will return to the

ECCM operation.

screen showing ECCM KEY and LP KEY. The ap-

propriate keys are displayed for a successful fill.

(a) Initialize the DTD. Connect the DTD to

To erase selected loaded keys, press ZERO line-

the KEY connector.

select switch. A ZEROIZE screen appears. Press

YES or NO line-select switch. If YES is pressed, a

(b) With the FILL page selected, KEY line

ZEROIZED advisory is displayed, then fill screen

select key - Press.

reappears. If NO is pressed, fill screen reappears.

Press RTN line select switch to return to STBY

NOTE

screen when all keys are loaded.

Pressing RTN line select key on

d. Operation.

KEY FILL page stops the fill proc-

ess.

(1) Starting Procedure.

(a) Function switch - STBY. SYSTEM

lect key - Press. FILL ENABLED message will ap-

TESTING is displayed while power up built in test

pear.

(PBIT is in process. SYSTEM - GO will be dis-

played upon successful completion of PBIT.

(d) Start keyfill on DTD. Monitor DTD to

see when data transfer is complete.

(b) FILL line select key - Press. Status of

(4) Zero Secure Keys.

PRE, ALE, ECCM, and EMER modes will be dis-

played.

(a) Access KEY FILL page. From FILL

screen, KEY fixed function key - Press. Select key

(2) Load Presets. Datafill contains preset fre-

to zero with VALUE keys.

quencies, scan lists, addresses, data messages,

and non secure information needed for ALE/ECCM

operation. If the DTD is configured to receive

(b) ZERO line select key - Press.

data, it may be copied from the radio to the DID

by pressing COPY line select key on the DATA

NOTE

FILL page.

(a) Initialize the data transfer device

If you do not want to zero the

(DTD). Connect the DTD to the DATA connector.

key, press NO. The FILL screen

will then appear.

(b) With the FILL page selected, DATA line

select key - Press.

lect key. ZEROIZE advisory message will appear,

followed by the FILL screen.

Change 18

3-22.7

TM 55-1520-210-10

AN/ARC-220 Messages

ADVISORY

ACTION

ALE - NO DATA

ALE mission data not loaded.

Load mission data.

ALE - NO KEYS

ALE link protection keys not

Load keys.

loaded.

CALL FAIL

Radio failed to complete an out-

going call.

CALLING

Radio is placing an ALE - call to

another address.

CHANNEL BUSY

ALE or ECCM net is in use.

Walt or try another net

CHANNEL INOP

ALE or ECCM keys are not

loaded, or not correct.

CHECK MSG

A data message has been re-

ceived.

COPY COMPLETE

Copying process finished suc-

cessfully.

COPY FAIL

Copying process was unsuccess-

ful.

COPYING DATA

The radio is copying datafill con-

tents from DTS.

ECCM - NO DATA

ECCM data not installed.

Load mission data.

ECCM - NO KEYS

ECCM keys not Installed.

Load keys.

EMER

Mode or net selected for emer-

gency communication Is inopera-

tive.

EMERG - NO KEYS

No keys available for net selected Load keys.

for emergency communication.

EOM

End of message.

EXT FAIL

Radio failed due to external de-

vice, such as antenna.

Change 18

3-22.9

TM 55-1520-210-10

AN/ARC-220 Messages (Cont)

ADVISORY

MEANING

ACTION

GO DATA

Link quality analysis values too

low for reliable voice communica-

tion; data transmissions recom-

mended.

HELD

ALE call being held in specific

frequency by operator.

INCOMING CALL

Another radio is establishing an

ALE link.

INOP MODES EXIST

Warning to expect inoperative

modes.

LINKED

An ALE link is established.

LOAD COMPLETE

Keys and data successfully

loaded into radio.

LOAD FAIL

Keys and data not successfully

loaded into radio.

LOADING DATA

Radio currently loading data.

LOADING KEYS

Radio currently loading keys.

MSG ABORT

Radio discontinuing sending of

current message.

NET INOP

Selected net contains no data,

corrupted data,or hardware can-

not support the selected mode of

operation.

NO AUTO XMT

Radio has been instructed not to

make any automatic transmis-

sions.

NO DATA

Database is not filled with neces-

sary data to perform requested

operations.

NO KEYS LOADED

Keys are not loaded for current

selected mode or net.

3-22.10

Change 18

TM 55-1520-210-10

AN/ARC-220 Messages (Cont)

ADVISORY

MEANING

ACTION

NO RCVD MSGS

No messages have been re-

ceived.

PAC FAIL

Failure of radio in PA coupler.

PRE - NO DATA

Preset data not loaded.

PTT FOR XMlT BlT

Instruction to press microphone

PTT switch to enable transmis-

sion BIT.

RCV BIT - GO

Receiver BIT functions completed

without failure.

RCV READY

Ready to receive ECCM trans-

missions.

RCVG PREAMBLE

ECCM preamble being received.

RCVG DATA

Radio currently receiving data.

RT FAIL

Receiver Transmitter inoperative.

RX - TX DEGRADED

Receive and transmit capabilities

are degraded.

RX - TX FAIL

Radio cannot receive or transmit.

SENDING DATA

Radio currently sending data.

SOUND

Radio sending an ALE sound.

SYNCING

Time synchronization being per-

formed.

TESTING

BIT in progress.

TIME SYNC FAIL

Radio failed in attempt to syn-

chronize.

TRANSEC FAIL

BIT detected a failure that will

not allow ECCM operation.

Change 18

3-22.11

55-1520-210-10

e. Modes of Operation.

NOTE

If the radio breaks in and out of

(1) Manual (MAN) Mode. Use manual mode

squelch, Increase setting as re-

to change transmit and receive frequencies, side-

quired.

bands and transmit power, and operate the radio

manually.

5. -SQL+ switch - Set squelch to 1.

(a) To change radio settings:

6. Select the desired net (1 through

20),

net selector switch -1 through +. Use VALUE

1. Mode switch - MAN.

keys to select 7 through

20.

2. Function switch - T/R.

7. ICS Transmitter selector - Position

2. Select the desired net (I through

20),

8. Radio push-to-talk switch - Press to

net selector switch -

1 through +. Use VALUE

talk; release to listen.

keys to select 7 through 20.

(2) Preset (PRE) Mode. Preset mode stores

2. EDIT line select key - Press.

preprogrammed frequencies and emission modes

that cannot be changed by the operator. To use

the radio in preset mode, do the following:

NOTE

(a) Function switch - T/R

Changing the receive frequency and

mode will also change the transmis-

(b) Mode switch - PRE.

sion frequency and mode the same

values. Changing the transmission

frequency and mode will not change

the receive frequency and mode.

(d) VOL switch - Adjust for comfortable

listening level.

5. Edit frequency, emission mode and

NOTE

transmit power by placing the cursor under field

If the radio breaks in and out of

to be edited with CURSOR key, and change field

squelch, increase setting as re-

value with VALUE keys.

quired.

6. To end edit and store changed data,

(e) -SQL+ switch - Set squelch to 1.

RTN line select key - Press.

(f) Select the desired net (1 through 20),

(b) To operate in manual mode:

net selector switch - 1 through +. Use VALUE

keys to select 7 through 20.

1. Function switch - T/R.

(g) ICS Transmitter selector - Position 4.

2. Mode switch - MAN

NOTE

3. -SQL+ switch - Set squelch to 0.

If tune tone is heard, wait until it

stops before talking. When radio

4. VOL switch - Adjust for comfortable

push-to-talk switch is pressed,

listening level.

XMT frequency is displayed. Dis-

play returns to preset display

when switch is released.

Change 18

3-22.13

TM 55-1520-210-10

(h) Radio push-to-talk switch - Press to

6. SQL+ switch - Set squelch to 0.

talk; release to listen.

7. To synchronize time in a link pro-

tected channel, SYNC soft key - Press.

(3) Automatic Link Establishment (ALE)

Mode.

8. To broadcast AN/ARC-220 system

time as net control, EDIT, then TXTIM soft keys -

Press. Time will be transmitted, and radio will re-

WARNING

turn to scan mode.

(b) To receive a ALE call:

When In ALE mode, the radio

transmits

Interrogating

signals

1. INCOMNG CALL is displayed, fol-

(sounds) and replies to ALE calls

lowed by the caller’s ALE address. A short tone

automaticalty without operator ac-

tion. To avoid personnel Injury,

sounds, and LINKED is displayed.

ensure the function switch Is not

set to ALE when personnel are

2. Transmitter selector - Position 4.

working near the helicopter, during

refueling or loading ordinance.

NOTE

Wait for the calling station to make

the first transmission.

Self address must be selected be-

3. Radio push-to-talk switch - Press to

fore using, ALE.

talk; release to listen.

ALE mode may be used for communications,

either normal or link protected, or position report-

ing.

1. Select ALE address:

(a) To set up the radio for ALE communi-

a. Select the desired net (1 through

cations, do the following:

20), net selector switch - 1 through +. Use

VALUE keys to select 7 through 20. Net name

1. Function switch - T/R.

and address will be displayed.

2. Mode switch - ALE.

b. VALUE switch

- Press, to scroll

through address list.

3. Select the desired net (1 through 20),

net selector switch -

1 through +. Use VALUE

c. EDIT soft key - Press. Enter address

keys to select 7 through 20.

one character at a time with CURSOR and VALUE

switches. To accept the edit and return to ALE

4. -SQL+ switch

- Set squelch to

screen, RTN soft key - Press.

TONE.

2. ICS Transmitter selector - Position 4.

5. VOL switch - Adjust for comfortable

listening level.

NOTE

Press ABORT to stop the calling

process.

Earphone audio is muted until a

link is established. If the link is

3. Radio push-to-talk switch - Press.

noisy, set squelch to 1. Higher

CALLING, then LINKED is displayed with a short

squelch settings are not recom-

gong tone in headphone.

mended in this mode.

3-22.14

Change 18

55-1520-210-10

NOTE

(b) To communicate in ECCM only mode,

ALE will cancel the link, and return

do the following:

to scan mode if there is no activity

on a link for 60 seconds. To main-

-,SQL+ switch

- Set squelch to

tain a link, press HOLD soft key.

TONE.

When communications are com-

plete, or to return to scan mode,

2. VOL switch - Adjust for comfortable

press SCAN soft key.

listening level.

(d) Radio push-to-talk switch - Press to

talk; release to listen.

NOTE

(e) When communication is complete, to

If the frequency is noisy, set squelch

return to scanning mode, HOLD, then SCAN soft

to 1. Higher squelch settings are not

key - Press.

recommended in this mode.

(4) Electronic Counter Countermeasures

3. -SQL + switch - Set squelch to 0.

(ECCM) Mode. The radio changes frequency in a

sequence determined by the ECCM key. Datafill

4. Press and hold the push-to-talk

and keyfill must be loaded prior to using ECCM

switch until XMT READY is displayed. Walt for

mode, and system time must be synchronized be-

preamble tones to stop.

tween stations. Frequencies used in hop sets are

pretuned in the radio, as ECCM requires frequen-

5. Talk. Release switch to listen.

cies to be changed many times per second. Fre-

quency hopping is performed in both standard

(c)To communicate in ALE ECCM mode,

ECCM and ALE modes of operation. To use this

do the following:

mode, do the following:

1. -SQL+ switch

- Set squelch to

(a) Initialize the net

TONE.

1. Function switch - T/R.

2. VOL switch - Adjust for comfortable

listening level.

2. Mode switch - ECCM.

3. Select the ALE address, as required

NOTE

with VALUE switches, or use EDIT soft key, then

If the selected net Is an ALE ECCM,

CURSOR and VALUE switches to manually select

the address of the station being

an address.

called is also displayed.

4. When an incoming call is being re-

2. Select the desired net (1 through 12),

ceived, INCOMING CALL, then LINKED is dis-

net selector switch - 1 through +. Use VALUE

played. RCV READY is displayed while the ECCM

keys to select 7 through 12.

information is being received, and disappears

when receive sequence Is completed.

3. To change values on screen, EDIT

soft key - Press. Use CURSOR to position cursor

5. To place a call, press the push-to-talk

under area to change, and VALUE to change the

switch. CALLING, then LINKED is displayed. Press

field to desired value.

and hold the push-to-talk switch, and wait for the

ECCM preamble tone to stop. When XMT READY

5. To save changes and return to top

is displayed, begin talking. When the transmission

level screen, RTN soft key - Press.

is completed, release the switch. XMT READY

disappears when the ECCM postamble is sent.

6. Push-to-talk switch - Press, to tune

and time synchronize the radio.

Change 18

3-22.15

TM 55-1520-210-10

2. To insert a word from the dictionary

(5) Message Mode. The radio can store up

in a message do the following:

to 10 transmit data and 10 received data mes-

sages. Each message may be 500 characters

a. Position cursor where the word is to

long. Messages are numbered from 1 to 10. Mes-

be inserted.

sage 10 is the oldest, and will be deleted if a new

message is received. Messages may be composed

b. WORD soft key - Press.

using the AN/ARC-220 CDU dictionary or with a

custom dictionary listing locally generated words,

c. Select the word with VALUE keys,

which may be loaded with datafill.

d. To insert word with blank in mes-

(a) To view a received message:

sage, SELECT soft key - Press. If desired, return

to message without inserting a word by pressing

1. MSG soft key - Press.

CANCL.

2. Use CURSOR keys to scroll left or

6. To load edited message in R/T mem-

ory and return to top level screen, RTN soft key -

right, or up and down in a message.

Press.

3. Use VALUE keys to page up and

down in a message.

(c). To send a message:

4. To view additional messages, position

1. Access PRGM MSG screen by press-

cursor under message number with CURSOR

ing MSG, then PRGM soft keys.

keys. Use VALUE keys to scroll to the next mes-

sage number.

2. Select message to send as desired by

placing cursor under message number, and press-

5. To retain received messages, RTN

ing VALUE keys until desired message is dis-

soft key - Press.

played.

6. To delete received messages, position

NOTE

the cursor under the message number and DEL

soft key - Press, until messages are deleted. To

Message will be sent to currently

return to top screen, RTN soft key -Press.

selected address (ALE modes) or

transmitted on the currently se-

lected frequency and mode (MAN,

(b) To edit or compose a message:

PRE, or ECCM).

1. MSG soft key - Press.

3. SEND soft key - Press.

2. From MESSAGE screen, PGRM soft

3-17.2. Voice Security Equipment TSEC/KY-

key - Press.

100.

3. Select message to be edited by plac-

a. Description. The Voice security equipment

ing cursor under the message number with

TSEC/KY-100 provides two-way clear or secure

CURSOR keys, and change number with VALUE

half-duplex voice or data communication for HF

keys.

Radio Set AN/ARC-220. Power to operate the

TSEC/KY-100 is supplied from the dc essential

4. Edit message by placing cursor under

bus through the KY-100 VOICE SCTY circuit

area to be changed. Use VALUE keys to change

breaker located on the pilot overhead circuit

one character at a time. Press DEL to delete one

breaker panel.

character at a time.

b. Controls and Functions for Remote Control

Unit (RCU). Refer to figure 3-14.2.

3-22.16

Change 18

TM 55-1520-210-10

Controls and Functions of Remote Control Unit TSEC/KY-100

CONTROL /INDICATOR

FUNCTION

1. CIK Receptacle

Interfaces with ‘C” Ignition ‘K” which enables all

secure voice and data communications. This function

is currently disabled.

2. Display

Liquid crystal display (LCD) that displays operational

status, operator prompts and messages as follows:

A. TX Annunciator

Displayed when KY-100 is transmitting.

B. RX Annunciator

Displayed when KY-100 is receiving.

C. WB Annunciator

Displayed when KY-100 is in wideband (VINSON)

configuration.

D. NB Annunciator

Displayed when KY-100 is in narrowband (ANDVT)

configuration.

E. EB Annunciator

Displayed when MODE switch is in emergency

backup (EB) position.

F. Alphanumeric Display

Displays prompts, messages, and operating modes.

G. PT Annunciator

Displayed when KY-100 is processing plain text

voice.

H. Key Symbol

Displayed when menu system is locked.

I. D Annunciator

Displayed when in data mode.

J. V annunciator

Displayed when in voice mode.

K. Bate Display

Displays voice or data rate.

3. FILL Connector

Used to load cryptographic keys through use of

common fill device such as KYK-13/TSEC Electronic

Transfer Device, KYX-15/TSEC Net Control Device,

AN/CYZ-10 Data Transfer Device (DTD), or KOI-

18/TSEC General Purpose Tape Reader.

3-22.18

Change 18

TM 55-1520-210-10

Controls and Functions of Remote Control Unit TSEC/KY-100 (Cont)

CONTROL /INDICATOR

FUNCTION

4. PRESET Switch

Eight position rotary switch that controls unit oper-

ating power and settings stored in memory as fol-

lows:.

OFF

Removes power from KY 100.

MAN

Manual position which allows operating modes to be

selected using both OFFLINE and on-line menu sys-

tem.

1 thru 6

Six separate preset modes which can only be set up

in OFFLINE mode.

5. PNL/OFF BRT Control

Two-function rotary switch that controls on/off

status and backlight intensity of LCD display.

6. Three Button Keypad Switches

Three momentary pushbutton switches that are ac-

tive in both OFFLINE and on-line modes. They are

used to enter and exit submenus, activate selected

mode, select fields, and to scroll through menus and

options as follows:

INIT Switch

In OFFLINE mode, activates displayed menu mode

and provides entry into submenus. In on-line modes

(CT, RK, EB, PT), selects display field to be changed.

Up Arrow (?) Switch

In OFFLINE mode, scrolls through menus from top to

bottom. In online modes (CT, RK, EB, PT), scrolls

through available options for display field being

changed. When used simultaneously with right ar-

row (4 switch, exits submenu.

Right Arrow (4 Switch

In OFFLINE mode, scrolls through menus from bot-

tom to top. In on-line modes (CT, RK, EB, PT), se-

lects display field to be changed. When used simul-

taneously with up arrow

switch, exits submenu.

7. DSPL/OFF BRT Control

Two-function rotary switch that controls on/off

status and backlight intensity for front panel.

Change 18

3-22.19

TM 55-1520-210-10

Controls and Functions of Remote Control Unit TSEC/KY-100 (Cont)

CONTROL /INDICATOR

FUNCTION

8. Mode switch

Six-position rotary switch that selects the following:

modes of operation:

Plaintext mode to allow reception or transmission of

unencrypted analog voice.

Emergency Back-up mode to use emergency back-up

key to encrypt voice for transmission or reception.

Ciphertext mode to allows transmission of encrypted

voice or data and reception of encrypted or unen-

crypted voice or data, and non-cooperative terminal

re-keying.

Remote keying mode to allow KY-100 to perform

automatic and manual rekey operations.

OFFLINE

Disables communications and accesses system

menus to allow mode selection, self-test operation,

and data fills with cryptovariables.

Z ALL

Zeroize mode to erase all cryptographic data stored

(PULL)

in KY-100 except emergency back-up key. Switch

must be pulled before setting it to this position,

3-22.20

Change 18

TM 55-1520-210-10

c. Operation.

1. Set MODE switch to OFL position.

NOTE

2. Rotate DSPL and PNL switches

During all operation procedures the

clockwise, out of OFF detent positions and adjust

KY-100 processor MODE switch is

display and panel lighting for comfortable viewing.

set to CT and PRESET switch to

REM.

3. Set PRESET switch to MAN (manual)

position to apply power to KY-100. Power-on

(1) Turn-On Procedures.

tests will automatically be run when primary

power is applied.

NOTE

4. Upon

successful

completion of

When KY-100 is turned on, tests are

power-on tests, test results should appear on dis-

automatically performed to deter-

play. If PASS is displayed, continue with turn-on

mine equipment’s operating status.

procedures. However, if FAIL message appears

The results of these tests will be

on display, notify next level of maintenance. If

presented on display.

Also, CLd

PUSH INIT is displayed, perform cold start proce-

START message will be displayed.

dures as described above in paragraph (a).

(a) Cold start turn-on.

(2) Key Loading Procedure.

1. Turn on KY-100 by setting PRESET

NOTE

switch to MAN position.

Key loading may be accomplished

2. The KY-100 will initiate self-test.

using AN/CYZ-10, KYK-15, KYK-13

The display reads CLd STRT and then PSH INT.

or KOI-18. One Key Encryption Key

(KEK), up to six Traffic Encryption

3. Connect fill device to KY-100 fill

Keys (TEKs), and one Emergency

connector using fill cable. Select fill position con-

Backup (EB) key can be loaded in

taining valid key and turn it on.

KY-100. A Fill Cable (ON190191) is

required when using one of these

4. Press INIT pushbutton switch.

devices. Proceed with the following

generic Key Loading procedures:

5. The KY-100 displays KEY 1 O1,

PASS.

(a) Set MODE switch to OFFLINE position.

NOTE

(b) If KY-100 is not on, turn PRESET

If fill device is not connected to KY-

switch to MAN position.

100 when INIT pushbutton is

pressed, dEV ERR (Device Error)

message will be displayed and an er-

nector

ror tone will be heard in the headset.

When this occurs, the only available

(d) Press up arrow or right arrow pushbut-

communication mode will be PT

ton switch until KEY OPS is displayed.

(Plaintext).

(e) Press INIT pushbutton switch. LOAD

6. If FAIL message is displayed,

KEY will be displayed.

notify the next level of maintenance.

(f) Press INIT pushbutton switch. LOAD

7. To load additional keys (up to a total

n with flashing n will be displayed. The flash-

of 6), proceed to Key Loading Section.

ing n indicates currently selected key location.

(b) Normal Turn-On.

Change 18

3-22.23

TM 55-1520-210-10

(g) Press up arrow or right arrow push-button

2. If KY-100 is on when this procedure

switch until required location (1, 2, 3, 4, 5, 6, or U) is

is performed, ZEROED will be displayed, and tone

#splayed.

will be heard.

(h) Press INIT pushbutton switch. The

3. If KY-100 power is on when MODE

entire LOAD n message will now be flashing.

switch is rotated out of Z ALL position, PUSH.

INIT will be displayed

(i) Turn on fill device and select key to be

loaded.

(b) Zeroize Specific Key Locations.

NOTE

1. Set MODE switch to OFFLINE posi-

tion.

Do not press INIT pushbutton switch

(or pull tape through tape reader) on

2. If KY-100 is not on, set PRESET

fill device.

switch to MAN position.

(j) Press INIT pushbutton switch. (When

3. Press up arrow or right arrow push-

using KOI-18 pull tape through tape reader at

button switch until KEY OPS is displayed.

steady rate after terminal INIT pushbutton switch

is pressed). Upon completion of successful load,

4. Press INIT pushbutton switch. LOAD

pass tone will be heard and display will momen-

KEY will be displayed.

tarily indicate KEY n, where n is key location

loaded.

5. Press up arrow or right arrow push-

button switch until ZERO is displayed.

(k) The display will again show LOAD n

with n flashing. To load additional keys, repeat

6. Press INIT pushbutton switch. ZERO

steps (g) through (j) until all desired key locations

n with flashing n will be displayed. The flashing n

have been loaded.

indicates currently selected key location to be ze-

roized.

(I) Turn off and disconnect fill device from

KY-100.

7. Press up arrow or right arrow push-

button switch until required location

(1,

(m) Rotate MODE switch out of OFFLINE

5, 6, or U) is displayed.

to exit Key Load.

8. Press INIT pushbutton switch. The

(3) Zeroize Procedures.

entire ZERO n message will now be flashing.

(a) Zeroize All Keys.

9. Press INIT pushbutton switch. The

display will go blank while key zeroize process is

NOTE

being performed. Upon completion of successful

key zeroizing, pass tone will be heard and display

This procedure is active even if pri-

will briefly indicate ZEROED n, where n is key lo-

mary power is removed from KY-

cation.

100. All key locations within KY-

100 will be zeroized. Once zeroized,

10. To zeroize additional keys, wait until

only PT voice communications are

display indicates ZERO n (with n flashing), then

possible until new Traffic Encryption

repeat steps 7 through 9.

Key (TEK) is loaded.

11.

Rotate MODE switch out of

1. Pull MODE switch and rotate it to Z

OFFLINE position to exit key load.

ALL position. All keys stored in locations 1-6 and

U will be erased.

3-22.24

Change 18

TM 55-1520-210-10

(4) Online Mode Selection Menu Procedure

(m) After all fields have been set properly,

press INIT pushbutton switch to save settings and

NOTE

return to standard operation procedures.

This procedure is used to modify

(5) Cipher/Plain Text Volume Level Modifica-

Online Mode configuration.

tion Procedure.

(a) Set MODE switch to CT position.

NOTE

(b) Set PRESET switch to MAN position.

The following procedure are used to

If PRESET switch is in position 1, 2, 3, 4, 5, or 6,

modify Receive Cipher Text Volume

mode selections cannot be modified.

Refer to

Level, Receive Plain Text Volume

section on changing preset settings to modify pre-

Level, and CT/PT or Cipher Text

set configuration.

Only menus.

(a) Set MODE switch to CT position.

(wideband) or NB (narrowband) enunciator, as

applicable, will begin flashing.

(b) Set PRESET switch to MAN

position.

NOTE

The KY-100 will be operated in nar-

rowband mode only with ARC-220

To modify Receive Ciphertext Vol-

Radio Set.

ume, proceed to step (c). To modify

CT/PT or Ciphertext Only setting,

(d) Press up arrow pushbutton switch until

proceed to step (h). To modify Re-

desired enunciator (WB or NB) is flashing.

ceive Plaintext Volume, proceed to

step (m).

(e) Press right arrow pushbutton switch.

The mode field will be flashing.

ton switch until RXCTV n (where n represents

(f) Press up arrow pushbutton switch until

current receive level) is displayed.

desired mode setting (NT or PP) is flashing.

(d) Press INIT pushbutton switch. The n in

(g) Press right arrow pushbutton switch.

RXCTV n will begin to flash.

The modem field will be flashing.

(e) Press up arrow or right arrow push-

(h) Press up arrow pushbutton switch until

button switch until desired receive level is dis-

desired modem setting (HF, LS, or BD) is flashing.

played.

(i) Press right arrow pushbutton switch.

(f) Press INIT pushbutton switch. The n in

The key field will be flashing.

RXCTV n will stop flashing.

(j) Press up arrow pushbutton switch until

(g) Press up arrow or right arrow pushbut-

desired key location (1, 2, 3, 4, 5, or 6) is flash-

ton switch until operating mode is displayed. This

ing.

completes Receive Ciphertext Volume adjustment.

(k) Press right arrow pushbutton switch.

(h) Press up arrow or right arrow pushbut-

The data rate field will be flashing.

ton switch until CT or CT ONLY is displayed.

(I) Press up arrow pushbutton switch until

(i) Press INIT pushbutton switch. The

desired data rate

(300,

600,

1.2K, or 2.4K) is

CT or CT ONLY will begin to flash.

flashing.

Change 18

3-22.25

55-1520-210-10

(j) Press up arrow or right arrow push-

button switch until CT (Ciphertext and Plaintext

switch to PT position. The CT, CT ONLY menu

operation) or CT ONLY (Ciphertext only operation)

must be set for CT to be able to transmit or re-

is displayed.

ceive plaintext messages. When transmitting in

plaintext, TX enunciator will be lit. When receiv-

(k) Press INIT pushbutton switch. The CT

ing plaintext message, RX and PT enunciators will

be lit. Refer to the following for Setting Summa-

or CT ONLY will stop flashing.

ries:

(I) Press up arrow or right arrow push-

TESC/KY-100 Setting Summary

button switch until operating mode is displayed.

This completes CT/PT or CT ONLY setting.

PRESETS

Narrow Band,

(m) Press up arrow or right arrow push-

button switch until RXPTV n (where n represents

current receive level) is displayed.

NT,

TEK I,

(n) Press INIT pushbutton switch. The n in

Rate 24,

RXPTV n will begin to flash.

BD.

AUDIO-DATA INTERFACE

(o) Press up arrow or right arrow push-

button switch until desired receive level is dis-

Menu Item

Setting

Default

played.

GUARD

GRD OFF

YES

(p) Press INIT pushbutton switch The n in

MIC

MIC UNBAL

YES

RXPTV n will stop flashing.

BALANCE

RX UNBAL

YES

IMPED

150 OHMS

(q) Press up arrow or right arrow push-

DAT SENS

MARK +

YES

button switch until operating mode is displayed.

RX COUP

RX AC

YES

This completes Receive Plaintext Volume adjust-

TX COUP

TX AC

YES

TX CLK

J2-V

YES

ment.

RADIO INTERFACE

(6) Normal Operating Procedures.

NOTE

You must go through the Narrow Bend

selection to get to the following menus.

These procedures describe normal

transmit/receive operation for cipher-

Menu Item

Setting

Default

text and plaintext voice messages.

TX CLKS

EXT CLK

TRN SEQ

YES

(a) Set PRESET switch to MAN (for man-

TX DELAY

135 ms

YES

ual selection) or desired preset position,

PREAM

ENHAN

DAT SENS

MARK -

YES

(b) For ciphertext operation, set MODE

CTS-BD/BDL

188

switch to CT position. Ciphertext messages can

CTS-HF/PT

188

now be transmitted or received. If CT, CT ONLY

CTS-LOS

188

menu is set for CT, plaintext messages can also

MILSTAR

OFF

YES

be received. When transmitting in ciphertext, TX

TX LVL

YES

and V enunciators will be lit. When receiving ci-

IMPED

150 OHMS

phertext message, RX and V enunciators will be

RTS/PTT-BD/BDL

RTS

RTS/PTT-HF

PTT

lit. When receiving plaintext message, PT enun-

RTS/PTT-LOS

PTT

ciator will be lit.

RTS/PTT-PT

PTT

3-22.26

Change 18

TM 55-1520-210-10

(7) Operating Tests

c. Press INIT pushbutton switch to

access TEST submenus.

(a) Fail Message Test

d. Press up arrow or right arrow push-

NOTE

button switch until desired sub-menu option

(AUTO or USER) is displayed.

Follow these procedures if KY-100

displays FAIL message during

e. Proceed to paragraph 2, 3, or 4, as

equipment configuration or normal

applicable.

operation.

2. Automatic (AUTO) Tests.

1. Set PRESET switch to PWR OFF posi-

a. With AUTO displayed, press INIT

pushbutton switch to start automatic tests.

2. Set MODE switch to OFL position.

b. At conclusion of automatic tests,

3. Set PRESET switch to MAN.

test results will be displayed.

4. If KY-100 does not display FAIL mes-

c. If automatic tests are successful,

sage after self test, return to normal operation.

PASS will be displayed end pass tone will be

heard. Next, display will indicate USER which is

5. If KY-100 does display FAIL message

next sub-menu. To perform USER tests, proceed

after self test, set PRESET switch to PWR OFF

to paragraph 3. To exit, rotate MODE switch out

position.

of OFFLINE position.

6. Pull MODE switch and rotate it to Z

d. If failure is detected during automatic

ALL position.

tests, FAIL message will be displayed.

7. Perform Cold Start procedures.

3. User Test.

8. If KY-100 does not display FAIL mes-

a. With USER displayed, press INIT

sage after self test, return to normal operation.

pushbutton switch to start user tests.

9. If KY-100 does display FAIL message

b. PT LOOP will be momentarily dis-

after self test, notify next level of maintenance.

played to indicate that plaintext loopback test will

be performed. Next, PTT prompt is displayed.

(b) Off-Line Test.

c. Depress and hold PTT switch and,

NOTE

with TALK prompt displayed, speak into micro-

phone. Looped back plaintext voice will be heard

The off line TEST menu consists of

in handset receiver.

automatic (AUTO) tests, user-

selectable (USER) tests and soft-

d. Release PTT switch.

ware version (VERSION) checking

procedures.

e. CT LOOP will be momentarily dis-

played indicating that KY-100 is In cipher text

1. Preliminary.

loopback mode. Next, PTT operator prompt is

displayed.

a. Set MODE switch to OFL position.

f. Press end hold PTT switch and,

b. The display will indicate TEST

with TALK prompt displayed, speak into micro-

which is the first OFFLINE menu.

phone until TALK prompt disappears (approxi-

mately 15 seconds).

Change 18

3-22.27

TM 55-1520-210-10

g. Release PTT switch. The LISTEN

prompt is displayed. Listen to synthesized speech

n. Set MODE switch to RK. OFL is

at receiver. Upon completion of speech loopback,

displayed.

observe that PANEL is displayed.

o. Set MODE switch to OFFLINE. Eb

NOTE

is displayed.

To exit end skip remaining USER

p. Set MODE switch to EB. PRESET

tests, press up arrow or right arrow

will be momentarily displayed, followed by MAN.

pushbutton switch within 5 seconds.

q. Set PRESET switch to MAN. A ‘1’

h. Within 5 seconds after completion

is displayed.

of CT loopback test, observe that all LCD seg-

ments are on. At completion of display test, mo-

r. Set PRESET switch to 1. A ‘2’ is

mentary MT operator prompt is displayed indicat-

displayed.

ing start of front panel switch test.

s. Set PRESET switch to 2. A ‘3’ is

NOTE

displayed.

Failure to perform any of the front

t. Set PRESET switch to 3. A ‘4’ is

panel pushbutton and switch prompts

displayed.

within 30 seconds will result in fail

tone and FAIL FP (Front Panel) display.

u. Set PRESET switch to 4. A ‘5’ is

displayed.

i. Press INIT pushbutton switch. A

right arrow is displayed.

v. Set PRESET switch to 5. A ‘6’ is

displayed.

j. Press right arrow pushbutton switch.

An up arrow is displayed.

w. Set PRESET switch to 6. A pass

tone will be heard indicating that front panel test

k. Press up arrow pushbutton switch.

was completed successfully.

PT is displayed.

x. Upon completion of USER tests,

l. Set MODE switch to PT. CT is dis-

menu will sequence to VERSION. Exit user test

played.

mode at this time by rotating MODE switch out of

m. Set MODE switch to CT. RK is dis-

OFFLINE position.

played.

Section III NAVIGATION

3-18. ADF Set AN/ARN-83

b. Controls and Functions. Refer to figure 3-

a. Description. The Automatic Direction Finder

set provides radio aid to navigation, on helicopter

c. Operation.

serial Nos. 66-746 and subsequent, within 190 to

1750 kHZ frequency range. In automatic opera-

(1) Automatic Operation.

tion, the set presents continuous bearing informa-

tion to any selected radio station end simultane-

(a) RECEIVERS NAV switch - ON

ously provides aural reception of the stations

transmission. In manual operation, the operator

(b) Mode selector switch - ADF

determines the bearing to any selected radio sta-

tion by controlling the aural null of the directional

antenna. The set may also be operated as a re-

ceiver.

(d) Volume - Adjust

3-22.28

Change 18

TM 55-1520-210-10

(2)

Manual Operation.

frequency is selected by tuning an associated

Iocalizer frequency on the control panel.

(a)

Mode selector switch-LOOP.

b. Controls and Functions. Refer to figure 3-18.

(b)

BFO switch-ON.

c. Operation.

loop for null.

(1)

Function switch-PWR.

3-19. ADF Set AN/ARN-59

(2)

RECEIVERS NAV switch-ON.

a. Description. The Direction Finder Set is a radio

(3)

Frequency-Select.

compass system to provide continuous automatic

visual indication of the direction from which an in-

(4)

VOL-Adjust.

coming selected radio signal is received. It may also

3-21. VHF Navigation Set-AN/ARN-30E

be used for homing and position fixing, or as a

manually operated direction finder. The control

a. Description. The VHF Navigation Receiver Set

panel, located in the pedestal, provides control for

provides reception of 190 channels at 0.1 MHz inter-

aural reception of AM signals in the 190 to 1750 kHz

vals between 108.0 and 126.95 MHz. The VOR ILS

range.

control panel is located on the pedestal and permits

reception and interpretation of VHF omnidirectional

b. Controls and Functions. Refer to figure 3-17.

range and Iocalizer signals broadcast by ground sta-

c. Operation.

tions. Line of sight operation varies from 12 nautical

miles at 100 feet altitude to 160 nautical miles at

(1)

Automatic Operation.

20,000 feet altitude.

(a)

ADF VOL control-ON.

b. Controls and Functions. Refer to figure 3-19.

(b)

RECEIVERS NAV switch-ON.

c. Operation.

(c)

Frequency-Select.

(1) VOL-OFF switch-On and adjust.

(d)

Function switch-COMP.

(2) SQUELCH control-Counterclockwise.

(2)

Manual Operation.

(3) Frequency selectors-Select.

(a)

Function switch-LOOP.

The warning flag for the vertical pointer is an indi-

cation of signal strength and reliability. Under no cir-

(b)

BFO switch-ON.

cumstances should navigation be attempted if the

flag is visible. If the TO-FROM indicator remains

blank, do not attempt VOR navigation.

loop for null.

(4) Vertical pointer and TO-FROM indicators (fig

3-20. VHF Navigation Set AN/ARN-82

3-20)-Masked.

a. Description. The Navigation Receiver set pro-

(5) SQUELCH control-Adjust.

vides reception on 200 channels, with 50 kHz spac-

ing between 108.0 and 126.95 MHz. This permits re-

3-22.

Course Deviation Indicators ID-453 and

ception of the VHF omnidirectional range (VOR) be-

ID-1347/

tween 108.0 and 117.95 MHz. The Vocalizers are re-

ceived on odd-tenth MHz, between 108.0 and 112.0

a. Description. The Course Deviation Indicator,

MHz and energized as selected. Both VOR and

used with the VHF Navigation Receiver system, is

Iocalizer are received aurally through the interphone

installed in the instrument panel (figs 3-18 and

system. The VOR is presented visually by the course

3-19). The purpose of the indicator is to depict

indicator and the number 2 pointer on the bearing

bearing and deviation of the helicopter from the se-

indicator and the Iocalizer is presented visually by

lected station. Also, information is presented from

the vertical needle on the course deviation indicator

the FM Receiver when the mode selector switch is in

(CDI) (fig 3-20). When the R-1963/ARN Glideslope/

HOME position (figs 3-10, 3-11, 3-12, and 3-13).

Marker Beacon Receiver is installed, the glideslope

When the R-1963/ARN Marker Beacon/Glideslope

Change 7

3-25

TM 55-1520-210-10

Receiver is installed, data is presented by the horizontal

pointer and GS warning flag.

(b) Free gyro mode.

b. Controls and Functions. Refer to figure 3-20.

1. COMPASS switch - DG or OUT

c. Operation.

Refer to the applicable VHF

2. Synchronizing knob - Set heading.

Navigation Receiver and/or FM Radio set operating

3. Annunciator

- Center position and then

procedures.

does not change (Annunciator is de-energized in the free

3-23. Gyromagnetic Compass Set.

gyro (DG) mode).

a. Description.

(1) The Gyromagnetlc Compass Set is a

1. Set the COMPASS switch to DG, OUT,

direction sensing system which provides a visual

MAG or IN as desired for magnetically slaved or free

indication of the magnetic heading (MAG) of the

gyro mode of operation. Free gyro (DG or OUT) mode is

helicopter. The information which the system supplies

recommended when flying in latitudes higher than 70

may be used for navigation and to control flight path of

degrees.

the helicopter.

2. When operated m the slaved (MAG or IN)

(2) A radio magnetic indicator is installed in the

mode, the system will remain synchronized during

pilot instrument panel.

A second radio magnetic

normal flight maneuvers. During violent maneuvers the

indicator (not shown) is installed in the copilots

system may become unsynchronized, as indicated by the

instrument panel. The copilot indicator is a repeater type

annunciator moving off center. The system will slowly

instrument similar to the pilot indicator except that it has

remove all errors in synchronization however, if fast

no control knobs. The moving compass card on both

synchronization is desired turn the synchronizing knob in

indicators displays the gyromagnetic compass heading.

the direction indicated by the annunciator until the

The number I pointer on the indicators indicate the

annunciator is centered again.

bearing to the NDB or course to the VOR station. The

3. When operating in the free gyro (DG or OUT)

number 2 pointer indicates the VOR course to station.

mode, periodically update the heading to a known

(3) The system does not have a fast-slewing’

reference by rotating the synchronizing knob.

feature. If the compass is 180° off the correct helicopter

heading when the system is energized it will take

3-24. Marker Beacon Receiver.

approximately I hour and 30 minutes (2’ per minute) for

a. Description. The Marker Beacon Receiver set Is

the compass to slave to the correct headings.

a radio aid to navigation. It receives 75 MHz marker

b. Controls and Functions. Refer to figure 3-21.

beacon signals from a ground transmitter to provide the

c. Operation.

pilot with aural and visual information. The marker

(1) INV switch - MAIN or STBY.

beacon controls and indicator are located on the

(2) Radio magnetic indicator (pilot only)

instrument panel to aid in determining helicopter position

Check power failure indicator is not in view.

for navigation or instrument approach.

(a) Slaved gyro mode.

b. Controls and Functions. Refer to figure 3-22.

c. Operation.

1. COMPASS switch - MAG or IN.

(1) VOLUME OFF/INCR control-ON.

2. Synchronizing knob - Center (Null) annunciatior.

(2) Receiver NAV switch (MB switch if SB-

3. Magnetic heading - Check.

329/AR panel is used) - On.

(3) Volume - adjust.

(4) SENSING HIGH/LOW switch-As desired.

d. Stopping Procedures. VOLUME OFF/INCR

control - OFF.

Change 17

3-29

TM 55-1520-210-10

CONTROL/INDICATOR

FUNCTION

Pointer No. I

Indicates course to ADF or VOR radio station.

Pointer No. 2

Indicates course to VOR station.

Synchronizing

Is manually rotated to null annunciator and synchronize

control

compass system.

SET HDG control

Moves the heading select cursor to desired heading.

Heading select

Indicates desired heading.

cursor

ADF/VOR control

Selects ADF or VOR for pointer No. 1

Fixed index

Provides reference mark for rotating compass card.

Rotating compass

Rotates under fixed index to indicate helicopter magnetic

card

heading.

Annunciator

Show dot (0) or cross (+) to indicate misalignment

(nonsynchronization) of compass system.

Power failure indicator

Shows to indications loss of power to compass system.

(OFF) (flag)

Compass switch

MAG or IN position slaved gyro mode DG or OUT position

(located on pilots

free gyro mode.

instrument panel)

Figure 3-21. Gyromagnetic Compass Indicator (RMI)

3-30

Change 17

TM 55-1520-210-10

3-24.1

Distance Measuring Equipment (DME)

(IFR) for enroute, terminal, and non-precision

AN/ARN-124.

approach phases of flight.

a. Description.

GPS signals are received by the AN/ASN-175

antenna (hereinafter referred to as the GPS

The AN/ARN-124 DME consists of a receiver-

antenna) where it is amplified and sent to the

transmitter (interrogator), antenna, indicator and

AN/ASN-175 receiver (hereinafter referred to as

hold light.

receiver/display unit) for processing. The receiver/

display unit also receives aircraft signals for

The interrogator is installed in the aft left radio-

magnetic compass heading, barometric altitude,

electronics compartment. The indicator and hold

and a 26 volt ac reference. Upon processing the

light are Installed on the pilot’s instrument panel.

input signals, the receiver/display unit provides

bearing, course, and distance data which are

The Indicator displays distance In nautical miles

displayed on existing aircraft navigation equipment

from the helicopter to the DME ground station and

when selected. The required amplification for the

controls power to the interrogator. The

bearing data from the receiver/display unit is

interrogator contains 200 channels covering a

provided by the AN/ASN-175 servo amplifier

frequency range of 962 MHz through 1213 MHz.

(hereinafter referred to as the servo amplifier). The

Signals from the interrogator are responded to by

receiver/display unit also provides outputs that

a DME ground station, resulting in a readout on

activate instrument panel mounted annunciators

the indicator. DME frequency selection is

for displaying the operational status of the

controlled by

the

VOR

control

panel,

AN/ASN-175

system. In

addition,

the

C-6873B/ARN-82. VOR-DME frequencies are

receiver/display unit provides a Have-Quick timing

automatically paired. The hold light is controlled

signal to any system requiring an accurate time

by the indicator. Illumination of the hold light

base. For the GPS installation, the Have-Quick

indicates a DME frequency is in the hold mode.

timing

signal

used

the

UHF

ILS glideslope indications are not possible with the

Receiver/Transmitter in Radio Set AN/ARC-

switch in the hold position. Use of the hold mode

164(V). When operating in the P(Y) mode, the

permits a change of VOR frequency without

AN/ASN-175 calculates the aircraft’s position to

changing the DME frequency. DME station

within 16 meters. It also provides destination,

identification is accomplished by a continuous

ground speed, ground track, estimated-time-of-

1350 Hz tone In the ICS. Power to operate the

arrival (ETA), and other relevant data to the

DME is from the dc essential bus, through the

operator.

The AN/ASN-175 uses receiver

DME ARN-124 circuit breaker.

autonomous integrity monitoring (RAIM) to

determine if a set of received GPS signals is

b. Controls end Functions. Refer to figure 3-23.

sufficient to maintain the required accuracy and

alerts the operator if the available GPS signals can

not support a 3-D solution. It also can predict

3-24.2 Satellite Signals Navigation Set AN/ASN-

RAIM conditions for approach arrival times. When

175.

access time to the GPS is less than optimum, the

AN/ASN-175 uses the magnetic compass heading

a. Description. The AN/ASN-175 is a navigation

and barometric altitude data inputs from the

management system that uses data from the

aircraft to validate its calculations and to

Global Positioning System (GPS) to calculate

supplement this data from the GPS. In addition,

position, velocity, and time (PVT). It calculates

the AN/ASN-175 protects against deception and

position in three dimensions

(3-D): latitude,

denial of the PVT service from the GPS. It does so

longitude, and altitude. The AN/ASN-175 utilizes

by providing an anti-jamming capability and by

a six channel protective code (P(Y)) continuous

implementing anti-spoofing Y-code functions.

tracking, dual frequency (L1/L2) compatible

Finally,

the

AN/ASN-175

includes

receiver, an omnidirectional flat L1/L2 antenna

comprehensive built-in-test (BIT) function that

with an integral preamplifier, and a 3-channel

runs when power is applied to the system. BIT

synchro amplifier. The AN/ASN-175 meets the

monitors the internal operation of the system and

performance standards for instrument flight rules

3-32 Change 18

55-1520-210-10

reports detected faults to the operator. Diagnostic

routines are also available to the

maintainer. Power to operate the AN/ASN-175 is

supplied from the 28 vdc essential bus through

he GPS ASN-175 circuit breaker on the pilot’s

overhead circuit breaker panel.

testing

Other components of the GPS installation include

a Remote Switch Assembly, a NO. 2 Bearing

Pointer switch, a GPS ZEROIZE switch, two Nav

select switch-indicator assemblies, two dual

display GPS annunciators, and two GPS FILL ports

(KYK and DATA). On aircraft equipped with the

AN/ARN-124 Distance Measuring Equipment

(DME) system, a DME indicator switch is also

included to allow the pilot to assign the DME

readout to either the GPS or VORTAC navigation

system. With the exception of the Remote Switch

and Servo Amplifier Assembly, these GPS

components are all located on the instrument

panel. The operation of all controls and indicators

on the receiver/display unit and the GPS controls

and indicators on the instrument panel is provided

in the controls and functions section that follows:

b. Controls and Functions. Refer to figures

3-22.1 and

3-22.2 and associated tables.

Change 18 3-32.1

TM 55-1520-210-10

Controls and Functions of Receiver/Display Unit

CONTROL/INDICATOR

FUNCTION

Display/Annunciators

Depending on operation, used to display advisory and

status information as follows:

A. Display Field

Provides two lines of high intensity light emitting diode

(LED) characters with 20 characters per line for dis-

playing information. The information displayed depends

on the operational mode and function selection.

B. Waypoint (WPT) Alert

Indicates that active waypoint is being approached.

Annunciator

The time between illumination of annunciator and

arrival at active waypoint may be selected by the

operator. The same WPT status information is

displayed on the external WPT annunciator.

C. Parallel Track (PTK)

Indicates that a track parallel to the direct course has

Annunciator

been selected. To display the selected offset, press the

MSG key.

D. Hold (HLD) Annunciator

Indicates that active flight plan has been suspended at

current active waypoint. The same HLD status infor-

mation is displayed on the external HLD annunciator.

E. Approach (APR) Annunciator

Indicates that aircraft is at or within two nautical miles

of final approach fix and that all approach require-

ments have been met. The same APR status infor-

mation is displayed on the external APR annunciator.

F. Receiver Autonomous Integrity

Indicates that AN/ASN-175 is unable to compute

Monitoring (RAIM)

RAIM. When RAIM annunciator is illuminated, the

Annunciator

AN/ASN-175 can not enable the approach mode.

G. Sensor Status (GPS)

Indicates that AN/ASN-175 is not providing a 3-D

Annunciator

solution.

H. Message (MSG) Annunciator

Indicates that one or more of the messages in the

queue is unread. When indication is steady, indicates

presence of one or more messages in the queue

requiring operator action. When indication is not

present, indicates that there are no messages in the

queue other than CDI scaling message. The same MSG

status information is displayed on the external MSG

annunciator.

Power Switch

Turns power to unit on or off. Power is turned on when

switch is rotated to ON (full clockwise) position.

Change 18 3-32.3

55-1520-210-10

Controls and Functions of Receiver/Display Unit (Cont)

CONTROL/INDlCATOR

FUNCTION

3. ENT (Enter) Key

Used in conjunction with MENU controls (inner and

outer selector knobs), this key enters, selects, or changes!

the information displayed. In general, the first press of

key opens an editable field on displayed page and the

second press accepts entered data.

4. MENU Control (Outer Selector

Scrolls through flight plan legs, secondary pages, and

Knob)

bottom lines of displayed mode and moves flashing

cursor between editable fields on displayed page.

5. MENU Control (Inner Selector Knob)

Scrolls through primary pages and top lines of displayed

mode and changes alphanumeric or available

option/function of any editable field.

6. D (Direct To) Key

Changes flight path. Used to fly direct-to any waypoint

in database and to activate a procedure or a flight plan.

In general, the first press of the pushbutton selects the

waypoint, procedure, or flight plan and the second

press activates course steering as selected (escape

provided by any other key).

7. MSG (Message) Key

Views system messages and displays current course

direction indicator (CDI) scaling. The MSG key will

flash until all massages have been viewed.

8. AUX (Auxiliary) Key

Accesses a variety of functions to include system

information and system status. Also used by maintainer

for testing and configuring the AN/ASN-175. Key

selection for all displayed functions is as follows:

Key Selection

Displayed Function

1st Press

System Status

2nd Press

Sensor Status

3rd Press

Configure

4^th Press

User Setup

5th Press

Install Setup

6th Press

Checklist

9. Navigation Database Card Slot

Accepts Navigation Database Card which contains the

database for use with the AN/ASN-175.

3-32.4

Change 18

55-1520-218-10

Connects and Functions of Reciever/Display Unit (Cont)

CONTROL/INDICATOR

FUNCTION

10. CALC (Calculator) Key

Accesses the capability to perform various com-

putations. Key selection for the displayed

computations is as follows:

*Key Selection

Displayed Computation

1st Press

Vertical Navigation Profile

2nd Press

flight Plan/Fuel

3rd Press

Air Data

11. FPL (Flight Plan) Key

Accesses four modes of flight planning available in the

AN/ASN-175. Key selection for the displayed modes is

as follows:

* Key Selection

Displayed Mode

1st Press

Active Flight Plan

2nd Press

Active Leg, Bearing,

Distance, and Estimated

Time Enroute

3^rd Press

Stored Flight Plans

4^th Press

Stored Leg, Bearing

Distance, and Estimated

Time Enroute

12. NAV (Navigation) Key

Views navigation and position information along

selected route. Key selection for the displayed

information is as follows:

*Key Selection

Displayed Information

1st Press

Primary Navigation

2nd Press

Waypoint Information

13. WPT (Waypoint) Key

Views and accesses information such as bearing and

distance, runway, name, frequencies, and position for

waypoints in the database. Key selection for the

displayed information is as follows:

*Key Selection

Displayed Information

1st Press

Mark Present Position

2nd Press

User

3^rd Press

Airport

4^th Press

Approach

5^th Press

SID

6^th Press

STAR

7^th Press

VOR

8^th Press

NDB

9^th Press

Intersection

Change 18 3-32.5

ARMY MODEL UH-1H/V HELICOPTERS. OPERATOR’S MANUAL (1988) - page 2