Icom IC-720A Instruction Manual page 22

| When an AFSK generator is used
PHONES „_
JACK
EXT
T/R SW
MIC PLUG
|
>
Mode to LSB. (See Other Operations chapter.) Doing this,
you can use the VOX operation available in this mode, and
receive/transmit changeover is very easy.
+ you wish to transmit continuously 10 minutes ог more,
reduce the output power to less than 70% of the full power,
by rotating the RF POWER control on the front panel.
TTY
MACHINE
60mA ог 20тА
LOOP
RTTY
DEMODULATOR
(TU)
LOOP CURRENT
POWER SUPPLY
SELECTOR
MAGNETS
ў SWITCH
AFSK
GENERATOR
5-5 AM OPERATION
5-5-1 RECEIVING
Set the operating mode for AM, by pushing the MODE
SELECT switch "AM". The other controls are the same as
those for SSB reception, except the Pass Band Tuning. The
Pass Band Tuning control does not work when the optional
crystal filter, FL-34, is not installed. The filter, F L-34 will
provide good selectivity and Pass Band Tuning capability
for AM reception. Refer to the installation instructions on
page 30.
When tuning an AM signal, tune for maximum signal
strength as indicated on the multi-function meter.
5-5-2 TRANSMITTING
Transmitting AM signals is essentially the same as SSB
transmission.
Set knobs and switches the same as for SSB operation.
The RF POWER control should be in fully clockwise
(COMP OFF) position. The output power in this mode, is
about 40 watts and cannot be reduced by rotating the RF
РОМЕН control. Also, the speech processor does not work.
When transmitting AM signals, the multi-function meter (in
RF position) will indicate the carrier power, and the meter
needle will move slightly according to your voice.
5-6 GENERAL COVERAGE RECEIVER
in this mode, the set does not transmit on any frequency,
even if the frequency is on the HAM band.
Set knobs and switches as follows.
POWER SWITCH
HAM/GENERAL COVER
SELECT SWITCH
OFF (OUT)
GENERAL COVER (IN)
T/R SWITCH RECEIVE (OUT)
VOX SWITCH OFF (OUT)
ATT SWITCH OFF (OUT)
AGC SWITCH SLOW (OUT)
NOISE BLANKER (NB)
SWITCH OFF (OUT)
VFO SWITCH "А" (OUT)
AF GAIN CONTROL
RF GAIN CONTROL
P.B. TUNE CONTROL
Completely Counterclockwise
Completely Clockwise
OFF or Center (12 o'clock)
position
RIT CONTROL Center (12 o'clock) position
The other controls are unrelated and need not be set for
this operation.
Now turn ON the power switch. The meter lamp will be
illuminated and [а 150000) will be shown on the
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