Standard Horizon HX400, Service Manual

Page: 7 / 40

HX400 Service Manual
Alignment
Alignment - 3
PLL Section
PLL Reference Frequency Adjustment
1. Connect the wattmeter, dummy load, and fre -
quency counter to the antenna jack.
2. Press the [
p
] or [
q
] key to
select the display to “ REF ”.
3. Press the [ SQL ] key, then
press the [ H/L ] key to enable
adjustment of the PLL Refer -
ence Frequency.
4. Press the PTT key to transmit
the transceiver, if necessary,
press the [
p
] or [
q
] key to adjust the frequency
so the counter frequency is 156.800 MHz (±100
Hz).
5. Press and hold the [ H/L ] key for 2 seconds to
save the new setting.
6. Press the [ CLR(WX) ] key to exit from this align -
ment item.
Receiver Section
Squelch Gain Adjustment
1. Connect the RF Signal Generator to the antenna
jack, and connect the DC voltmeter to TP4032
or TP5032 .
TP4032
or
TP5032
2. Press the [
p
] or [
q
] key to
select the display to “GAIN”.
3. Press the [ SQL ] key to enable
adjustment of the Squelch
Gain level.
4. Press the [
p
] or [
q
] key to
select a small character of
lower right corner of the dis -
play to “ C ”.
5. Set the RF Signal Generator output level 0
dBμV (with a standard FM modulation: ±3.0
kHz deviation @ 1 kHz) at 156.800 MHz.
6. Press the [ H/L ] key, then press the [
p
] or [
q
]
key so that the DC voltmeter reading is 0.3 V
(±0.05 V).
7. Press and hold the [ H/L ] key for 2 seconds to
save the new setting at the band center.
8. Press the [
p
] key to change
the “ C ” character to “ H ” at
the lower right corner of the
display.
9. Change the RF Signal Generator to 174.000
MHz. The output level keeps 0 dBμV (with a
standard FM modulation: ±3.0 kHz deviation @
1 kHz).
10. Press the [ H/L ] key, then press the [
p
] or [
q
]
key so that the DC voltmeter reading is 0.3 V
(±0.05 V).
11. Press and hold the [ H/L ] key for 2 seconds to
save the new setting at the high band edge.
12. Press the [
q
] key twice to
change the “ H ” character to
“ L ” at the lower right corner
of the display.
13. Change the RF Signal Generator to 134.000
MHz. The output level keeps 0 dBμV (with a
standard FM modulation: ±3.0 kHz deviation @
1 kHz).
14. Press the [ H/L ] key, then press the [
p
] or [
q
]
key so that the DC voltmeter reading is 0.3 V
(±0.05 V).
15. Press and hold the [ H/L ] key for 2 seconds to
save the new setting at the low band edge.
16. Press the [ CLR(WX) ] key to exit from this align -
ment item.