TM 11-6625-2629-14&P
CHAPTER 3
OPERATING
INSTRUCTIONS
Section I. CONTROLS AND INSTRUMENTS
3-2. Operator's Controls
3-1. Damage from Improper Settings
The controls and indicators for the modulation
The DEVIATION RANGE KC switch must be in
meter are on the front panel; their functions are
the 1000 TUNE position before energizing the
d e s c r i b e d in the following chart and their
equipment. Failure to do so could result in
locations shown in figure 3-1.
damage to the DEVIATION meter.
Table 3-1. Controls and Indicators
Function
Control, indicator, or connector
Turns modulation meter on or off.
POWER- switch
Permits operation from either 115 or 230 volts ac.
Line voltage eelector switch
Lights when POWER switch is at ON position.
Power indicator lamp
Indicates proper tuning and amount of shift of carrier frequency from resting
CARRIER SHIFT meter
frequency due to modulation.
Indicates adequate signal level when in black area.
LIMITING meter
Selects display range for CARRIER SHIFT meter.
TUNE-FINE TUNE switch
Action
Switch position
Sets CARRIER SHIFT meter for course
TUNE
tuning of modulation meter.
Sets CARRIER SHIFT meter for fine tuning
FINE TUNE
of modulation meter.
Indicates amount of deviation of fm signal.
DEVIATION meter
Selects one of 5 display ranges for DEVIATION meter.
DEVIATION RANGE-KC switch
Action
Switch position
Sets meter to read deviation to 20 kHz.
20
Sets meter to read deviation to 50 kHz.
50
Sets meter to read deviation to 100 kHz.
100
300
Sets meter to read deviation to 300 kHz.
Sets meter to read deviation to 1000 kHz.
1000 TUNE
Calibrated to indicate carrier resting frequency of signal input in megaHertz.
FREQUENCY MC dial
Selects one of 5 tuned circuits for local oscillator.
FREQUENCY RANGE-MC switch
Action
Switch position
Provides tuning of modulation meter, with use
20-65
of TUNING knob, between 20 and 55 MHz.
Provides tuning of modulation meter, with use
55-120
of TUNING knob, between 55 and 120 MHz.
Provides tuning of madulation meter, with use
120-250
of TUNING knob, between 120 and 250
MHz.
Provides tuning of modulation meter, with use
250-500
of TUNING knobs, between 250 and 500
MHz.
Provides tuning of modulation meter, with use
5OO-1OOO
of TUNING knob, between 500 and 1000
MHz.
P e r m i t s tuning of local oscillator over its entire range when used in
TUNING knob
conjunction with FREQUENCY RANGE-MC switch.
Permits convenient coupling of signal generators and transmittal coupling coils
INPUT connector
to modulation meter.
Permits aural monitoring of input signal modulation and monitoring of
AUDIO OUTPUT
distortion of input signal modulation when a spectrum analyzer is used.
Permits adjustment of signal level at AUDIO OUTPUT jacks.
AUDIO ADJ
.
3-1
