Sony XR-6380 Service Manual page 7

FM Auto-scan Stop Level Adjustment
Setting:
Note: Be sure to perform this adjustment be-
fore "AM Auto-scan Stop Level Adjust-
ment".
test tape — FM Discriminator Alignment
P-4-D400
(400 Hz, 0 dB)
AM Auto-scan Stop Level Adjustment
"FM Auto-scan Stop Adjustment".
Setup:
BAND: FM MONO
Frequency: 98.1 MHz
FM rf signal
generator
Note: center-zero meter should be of high in-
put impedance type.
Setup:
BAND: AM
Frequency: 1,000kHz
Procedure:
Adjust RV101 (L-CH) and RV201 (R-CH) to
obtain 0.45 V (—4.7 dB) reading on VTVM.
BAND: FM MONO
Frequency: 98.1 MHz
0.01 pF
ae to antenna input
FM rf signal
Adjustment Location: main board
PeveetOr
lands of main
board
0.01uF
—.
AM rf signal generator
Carrier frequency: 98.1 MHz
Mode: monaural, no modulation
to antenna input
lands of main
AM dummy
board Output level: 14 wV (23 dB) antenna
Carrier frequency: 98.1 MHz to sili j
ae
ioe '
input lands o
Modulation:
1 kHz, 75 kHz deviation (100%)
Procedure:
main board
1,000 kHz, 56 wV (35 dB)
no modulation
Procedure:
Output level: 1mV (60dB)
Mode: monaural
Adjust RV1 at the point where voltage reading
suddenly changes.
Procedure:
Change the FM rf signal generator output and
confirm that the point where voltage reading
suddenly changes is 19 +5 dB (14 dB to 24 dB).
Adjust RV51 at the point where voltage reading
Slowly adjust the core of T1 to obtain a zero (0) V suddenly changes.
reading on VTVM or zero-center d-c voltmeter.
Change the AM rf signal generator output and
confirm that the point where voltage reading
suddenly changes is 38 +7 dB (31 dB to 45 dB).
Adjustment Location: main board
Adjustment Location: main board
Adjustment Location: main board
_—ain
|
[MAIN BOARD] (Concluctor Side)
VTVM or high input
T1 FM Discriminator Alignment /™pedance center
zero meter
(range: 0.5 — 5 V de)
et enka ll a
|
|
VOM (dc range)
Q509
collector
{MAIN BOARD] (Conductor Side)
RV101 (L-CH)
RV1 FM Auto-scan Stop Level Adjustment
RV51 AM Auto-scan Stop Level Adjustment
|
|
|
| | | |
|
|
|
| | |
|
| E