2-3. RT SELF-TEST. Continued
place of the letter E. The next display is "88888. This lets you check that all display segments do light. While
the five 8s are being displayed, the control panel (local) or the control unit (remote) tests its circuits and the link
to the RT, Then the RT checks its programming, holding memory, and receive circuitry. The receive path is
checked at eight frequencies in SC mode and two frequencies in FH mode. The ECCM module performs a
separate self-test at this time. If the RT passes all checks, Good is displayed. If "FAIL1" is displayed, a fault
was found in the RT circuitry or programming. If "FAIL3" is displayed, a fault was found in the ECCM module, If
"FAIL7" is displayed, the interface between RCU and RT or local control panel and RT is bad. "FAIL8" indicates
failure of the control unit or control panel.
2-4. RT Z-A CHECK.
When the FUNCTION switch is set to Z-A, the RT checks memory as well as erasing it. "Good" will be displayed if
it passes the check. "FAIL1" or "FAIL3" indicates a failure in the RT.
2-5. RT TRANSMIT CHECK.
Loss of sidetone in the headset may mean a transmitter failure. Amplifier-oscillator heat sink temperature is
monitored. If it goes above 105°C, output power is reduced. Sidetone is disabled if RF output power drops below
about 4 watts, either from high voltage standing wave ratio (VSWR) or high temperature.
2-6. RT LOAD CHECKS.
When fill data is loaded in the RT for FH operation, the RT checks the parity of the fill data. If not correct, "bAd" is
2-7. DATA RATE ADAPTER CHECKS.
The DRA does self-test checks when its input power is applied. Upon failure, a continuous 1200-HZ tone is sent to
the intercom headset. If good, a beep is heard. The 1200-Hz tone may be stopped by pushing the headset PTT.
2-8. IFM POWER AMPLIFIER.
Partial or total loss of power in the power amplifier causes sidetone to be disabled when transmitting.
2-9. ECCM FILL DEVICE CHECK.
The CHECK indicator on the ECCM fill device is used to check for fill data. With the function switch at OFF and the
select switch to a position with fill data, the CHECK light will blink when the initiate switch is pressed.
Section Il. DESCRIPTION AND USE OF OPERATORS CONTROLS,
INDICATORS, AND CONNECTORS
ECCM Fill Device Controls, Indicators, and Connectors . . . . . . . . . . . . . . . . . 2-11
RT/RCU Controls, Indicators, and Connectors . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
2-10. RT/RCU CONTROLS, INDICATORS, AND CONNECTORS.
Below are illustrations of units used in the SINCGARS radio sets showing the location of controls, indicators,
and connectors. There are some differences that should be noted.
Non-lCOM compared to ICOM
Different names on some of the keyboard keys.
FUNCTION switches are different. The NonlCOM FUNCTION switch has a setting of LD-V, the ICOM
does not. This results in switch position locations varying between Non-lCOM and ICOM versions.
Receiver-Transmitter to Radio Set Control
No FILL connector on Radio Set Control
IFM RF PWR switch on upper left of RT, upper right of Radio Set Control
IFM RF PWR switch setting positions are different
Keyboard centered on Radio Set Control
MODE switch moved up on Radio Set Control
MODE switch setting positions are different
Volume (VOL) switch moved to right side on Radio Set Control