Vertex Standard VXA-710 SPIRIT, Service Manual

Page: 13 / 40

13
Alignment
TX AM Modulation (Hi) Adjustment
Connect the Radio Tester to the antenna jack, then
adjust the AF generator output level for injection of
200 mV rms @ 1 kHz to the
MIC jack.
Set the transceiver to 128.000 MHz and turn the trans-
ceiver off.
Press and hold in the PTT switch, MONITOR switch,
and key while turning the transceiver on to enter
the alignment mode.
Rotate the DIAL selector knob to select “
AM MOD Hi
xxx
.”
Press the PTT switch, and confirm that the modula-
tion level is 85 % modulation (±5 %).
If not:
1. Press the key momentarily;
2. Rotate the DIAL selector knob clockwise (increases the
MIC gain) or counter-clockwise (decreases the MIC
gain);
3. Press and hold the key for 1/2 second;
4. Confirm the modulation level.
Repeat steps 1 - 4, as necessary, until you achieve the
specified 85 % modulation level (±5 %).
Turn the transceiver off.
TX AM Modulation (Low) Adjustment
Connect the Radio Tester to the antenna jack, then
adjust the AF generator output level for injection of
200 mV rms @ 1 kHz to the
MIC
jack.
Set the transceiver to 128.000 MHz and turn the trans-
ceiver off.
Reduce the power supply voltage to 4.8 V.
Press and hold in the PTT switch, MONITOR switch,
and key while turning the transceiver on to enter
the alignment mode.
Rotate the DIAL selector knob to select “
AM MOD Lo
xxx
.”
Press the PTT switch, and confirm that the modula-
tion level is 85 % modulation (±5 %).
If not:
1. Press the key momentarily;
2. Rotate the DIAL selector knob clockwise (increases the
MIC gain) or counter-clockwise (decreases the MIC
gain);
3. Press and hold the key for 1/2 second;
4. Confirm the modulation level.
Repeat steps 1 - 4, as necessary, until you achieve the
specified 85 % modulation level (±5 %).
Return the power supply voltage to 7.4 V.
Turn the transceiver off.
Receiver Section
AM & FM Squelch Hysteresis Adjustment
Press and hold in the PTT switch, MONITOR switch,
and key while turning the transceiver on to enter
the alignment mode.
Rotate the DIAL selector knob to select “
AM
/
FM HITS
xxx
.”
Press the key momentarily, then adjust the hys-
teresis level using the DIAL selector knob (default:
001
).
Turn the transceiver off.
AM & FM Squelch Threshold Adjustment
Connect the Radio Tester to the antenna jack, and ad-
just its output level to –11 dBµ (with 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 key while turning the transceiver on to enter
the alignment mode.
Rotate the
DIAL
selector knob to select “
AM / FM TH SQ
xxx
.”
Press the key momentarily (you will hear a long
beep), then press and hold in the key (until you
hear the short beep).
Turn the transceiver off.
AM & FM Squelch Tight Adjustment
Connect the Radio Tester to the antenna jack, and ad-
just its output level to +10 dBµ (with 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 key while turning the transceiver on to enter
the alignment mode.
Rotate the DIAL selector knob to select “
AM
/
FM TI SQ
xxx
.”
Press the key momentarily (you will hear a long
beep), then press and hold in the key (you will
hear a short beep).
Turn the transceiver off.
NOTICE !
Do not touch the “
FM MA DEV xxx
,” “
FM Narw DEV
xxx
,” “
CTCSS DEV xxx
,” and “
N CTCSS DEV xxx
” pa-
rameters.