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RECEIVE SECTION ADJUSTMENT
Local Oscillator Coil
1. Tune the transceiver to about 145 MHz.
2. Turn
the slug of coil Ls8 clockwise
until oscillation
stops.
3. Then turn the slug back 360 degrees for stabie oscil-
lation.
Sensitivity
1. Connect
a signal
generator
to the external
antenna
connector.
3. Adjust coils Ls1, 2, 4... 7, 9, 10 and TCt3 {mounted
on the TRANSMIT
section PCB) until the meter reads
maximum with an optimum S/N ratio.
Discriminator Coil
1. Connect
a signal generator
to the external
antenna
connector and an oscilloscope to the output terminal.
2. Apply a signal (1 kHz modulation,
7 kHz frequency
deviation, 10 dB =3uV output) to the transceiver.
3. Align coils Ls12 and 13 until output waveform
is opti-
mum
on the oscilloscope.
S-Meter
1. Connect
a signal generator
to the external
antenna
_ connector.
2. Feed a 20 dB signal to the transceiver.
3. Adjust VRs1
until the meter deflects full scale (or
reads 10).
Note:
Meter reading below full scale calls for readjustment
of
sensitivity.
Squeich
Set the channel
selector knob to the channel
that con-
tains a crystal and confirm that there is no signal re-
ceived. With any signal not being received
adjust VRs2
until squelch opens between 9 and 2 o'clock.
Confirmations
1. The transceiver shall show no large difference in sen-
sitivity for a supply voltage range of 10.4 to 15.2
volts.
2. Sensitivity difference shall be within the specification
throughout the entire band including the band edges.
3. The
transceiver
shall
not
interfere
with
TV
channel
(176 to 182 MHz) after the local oscillator has been
aligned.
TRANSMIT SECTION ADJUSTMENT
Note:
Use
insulated
screwdrivers
for coil and
trimmer
adjust-
ments.
Multiplier and final stage
1. Connect a 50-ohm power meter to the external anten-
na connector.
2. Set the channel selector of Model
TR-2200G
to a
transmit
frequency
of 144.15
MHz
and connect
the
instruments as shown in Fig. 5.
Power meter
DC power supply
DC ammeter (1 amp}
TR-2200G
Fig. 5
3. Operate the transceiver
in the transmitting
state and
adjust TCt1, 3 - 10 at a supply voltage of from 9 to
10 volts until the ammeter reads maximum.
4. Increase the supply voltage to 13 volts and adjust
TCt1 and 2 for a maximum
output.
Note:
TCt2 should be set to a point at which the output is ap-
proximately 5% down with a minimum
current drain.
This is to be achieved by reducing trimmer capacitance.
Modulation
1. Set the supply voltage to 13 volts and connect
an
audio generator to the microphone connector.
2. Modulate
the carrier with a 1 kHz 5 mV
signal and
set the
transceiver
to the
transmit
state
at
144.15
MHz.
3. Observe
the waveform
on an oscilloscope
through
a
linear detector. Adjust Lt2 until and optimum
output is
obtained.
Adjustment Without Linear Detector
Apply a 3 mV, 1 kHz signal from the audio generator
to
the
microphone
input and
connect
an
audio
frequency
VTVM to terminal TO1 (X56-1080-00). Adjust VRt2 until
the meter reads 360 mV. As still another method, anoth-
er TR-2200G transceiver may be used as monitor.
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