OPE RATION
With the P0WER switch in the on (up) position and
sition, the transceiver should work in the normal
the PREAMP position, the pre-ampl ifier section of
of the receiving system and, therefore, since it
as fol lows:
the PREAMP swi tch i n the OUT po-
fashlon. With the PREAMP switch in
the PT then will increase the gain
is in operation, it should be used
l. Turn the MHz switch to a position that includes the desired frequency. For ex-
ample, the 2O-meter amateur band is'14 to 14.35 MHz. This is between the l0 and
23, therefore the switch must be at the line between l0 and 23.
2. When a signal is received, peak it by "alrrting the TUNING control for maximum
swing on the receiver S meter or maximum volume if no meter is used. ln tuning
over a band, the tuning knob of the PT should be adjusted fairly frequently. For
example, at AMHz, it may have to be adjusted every 50 kHz. At 50 MHz, it may
have to be adjusted every 200 kHz.
l. When the PREAMP switch is left in the OUT position, the unit is in standby con-
dition with power applied and its frame grid tube warmed up. lnstantaneous
pre-amplification is available when the switch is placed in the PREAMP position.
4. Because the PT adds considerable amplification (approximately 20 db) to the re-
ceiver section of the transceiver, which may often have sufficient gain, partic-
ularly on the lower frequency bands, overloading resulting in cross modulation or
desensitization, or both, may occur. For this reason, a manual GAIN control is in-
cluded on the front panel. Normally, this control should be turned fully clock-
wise; however, under strong Iocal signal conditions; it may often be found de-
sirable to reduce this control to a point where the local signals tune considera-
bly sharper and, therefore, occupy less space on the band. Although this will re-
duce the sensitivity, it will be very often found, particularly when desired
signals are strong, that reduction will provide an over-all and more usable sig-
nal than when the pre-amplifier was not in the circuit. This is particularly true
in those transceivers having considerable front-end gain without provisions for
separate RF gain and lF gain controls.
When switching the
tuning control , or
under certa i n cond i
ticularly with the
PT in and out of the circuit
both, at i ncorrect sett i ngs ,
t ions, an appreciable s i gnal
GA I N control at max imum. Th i s
with the band switch or the
i t wi I I be not iced that,
will still come through, par-
is normal .
Some'transceivers, having especially good AVC action, will tend to make tuning the
PT difficult, particularly on strong signals. This can be overcome by watching the
S meter very carefully while peaking the PT, peaking up on a weak signal, or peaking
up on the background noise in the absence of a signal. The true worth of the PT will
be more fully realized under extremely poor band conditions whenever signals are
very weak.
NOTE. lf the receiver sensitivity appears to be very Iow, regardless of
the setting of the band switch and the tuning control, the fuse/resistor
in the antenna circuitry should be checked. (ffre fuse/resistor in the
antenna circuitry is located on the underside of the chassis, at the
right front.)
