Main-B Unit Adjustment (Pcr2500 Only) - Icom IC-PCR1500 Service Manual

5-3 MAIN-B UNIT ADJUSTMENT (PCR2500 only)

ADJUSTMENT
BPF
[LT1]–[HTF]
–
AGC GAIN
(FM)
[AGF]
(AM)
[AGA]
IF GAIN
(FM)
[IFF]
(AM)
[IFA]
‡
The output level of the standard signal generator (SSG) is indicated as the SSG's open circuit.
*Displayed on the controller's display.
1 • Set the adjustment items as below before the "BPF" adjustment.
[AGA] : "8A"
[IFA] : "25"
2 • Connect an SSG to the antenna connector "ANT1" and set as;
Frequency : Specifi ed frequency*
Modulation : none
Level : Specifi ed level
3 • Push [SET•SKIP] to store the set value.
4 • Repeat 2–3 for each specifi ed frequency then level for [LT1] to [HTF].
1 • Connect an SSG to the antenna connector and set as;
Frequency : Specifi ed frequency*
Mode : FM
Deviation : 3.5 kHz
Level : +34 dBµ (–73 dBm)
Modulation : 1 kHz
2 • Connect a speaker and milliwatt meter and set the audio output level
to 50 mW with [VOL].
3 • Push [MAIN•NB] to select next adjustment item.
4 • Set the SSG as;
Frequency : Specifi ed frequency*
Mode : AM
Deviation : 70%
Level : +34 dBµ (–73 dBm)
Modulation : 1 kHz
5 • Set the audio output level to 50 mW with [DIAL].
• Verify that the demodulated audio signals are not distorted badly.
6 • Push [SET•SKIP] to store the adjustment value.
1 • Set the SSG as;
Level : OFF
2 • Connect a speaker and milliwatt meter then set the audio output level
to 50 mW with [VOL].
3 • Push [SET•LOCK]/[MAIN•NB] to select next adjustment item.
4 • Set the audio output level to 80 µW with [DIAL].
5 • Push [TS•MODE]/[SET•SKIP] to store the adjustment value.
OPERATION
†
‡
‡
5 - 5
VALUE
Automatic adjustment
50 mW
50 mW
50 mW
80 µW