Vertex Standard VXA-300 Pilot III, Service Manual

Page: 12 / 32

12
Alignment
PLL Section
PLL Reference Frequency
Connect the wattmeter, dummy load and frequency
counter connected to the antenna jack, then set the
transceiver to 128.000 MHz and turn the transceiver
off.
Press and hold in the PTT switch, MONITOR switch,
and VOLUME knob while turning the transceiver on
to enter the alignment mode.
Rotate the DIAL selector knob to select “
09 REF xxx
.”
Press the PTT switch, and confirm that the counter
reading is 128.000 MHz.
If not,
1. press the
VOLUME knob momentarily,
2. rotate the DIAL selector knob clockwise (frequency
up) or counter-clockwise (frequency down),
3. press the VOLUME knob again,
4. confirm the counter reading.
Repeat above steps 1 - 4, so that the counter reading is
128.000 MHz (±100 Hz).
Turn the transceiver off.
Receiver Section
AM Squelch Threshold Adjustment
Connect the Radio Tester to the antenna jack, then
adjust the output level to –9 dBµV (with a standard
AM modulation: 30 % AM modulation @ 1 kHz) at
128.000 MHz.
Set the transceiver to 128.000 MHz and turn the trans-
ceiver off.
Press and hold in the PTT switch, MONITOR switch,
and VOLUME knob while turning the transceiver on
to enter the alignment mode.
Rotate the DIAL selector knob to select “
01 AMTH xx
.”
Press the VOLUME knob twice.
Turn the transceiver off.
AM Squelch Tight Adjustment
Connect the Radio Tester to the antenna jack, then
adjust the output level to +10 dBµV (with a standard
AM modulation: 30 % AM modulation @ 1 kHz) at
128.000 MHz.
Set the transceiver to 128.000 MHz and turn the trans-
ceiver off.
Press and hold in the PTT switch, MONITOR switch,
and VOLUME knob while turning the transceiver on
to enter the alignment mode.
Rotate the DIAL selector knob to select “
02 AMTI xx
.”
Press the VOLUME knob twice.
Turn the transceiver off.
FM Squelch Threshold Adjustment
Connect the Radio Tester to the antenna jack, then
adjust the output level to –11 dBµV (with a standard
FM modulation: ±3kHz deviation @ 1 kHz) at 163.275
MHz.
Store Weather Channel ”WX-010” into a ”regular”
memory channel, per the instructions in the box to the
left.
Recall the memory channel into which you just stored
Weather Channel ”WX-010” in the previous step, then
turn the radio off.
Press and hold in the PTT switch, MONITOR switch,
and VOLUME knob while turning the transceiver on
to enter the alignment mode.
Rotate the DIAL selector knob to select “ 03 FMTH xx .”
Press the VOLUME knob twice.
Turn the transceiver off.
How to Store Weather Channel "WX-010"
into a Regular Memory Channel
Press the VOLUME knob (repeatedly, if neces-
sary) to select the Weather channel mode. The
VXA-300 will scan quickly through the Weather
channels.
Press the MONITOR switch momentarily to stop
the scanning, then rotate the DIAL knob to se-
lect the channel ”WX-010.”
Press and hold in the [ MW ( SPL-W
)] key for 2
second, then rotate the DIAL knob to select the
memory channel number for storage.
Now, press and hold in the [ MW ( SPL-W
)] key
for 2 second to save the entry and exit.