Toshiba 27a50 Service Manual page 15

MTS ADJUSTMENT (FOR N0ES CHASSIS)
No. ITEM
1
ATTENUATOR
(ATT)
2
STEREO VCO
(STVC)
3
STEREO FILTER
(STRF)
4 STEREO SEPARATION
(WBAN)
(SPEC)
5 SAP VCO
(SAVC)
INPUT SIGNAL
• 1kHz 30% mod. → ANT
terminal
• No signal
• 15.734kHz 30mV(rms)
15.734KHz 30mV(rms)
H001
QG01
10
SL02
+ CG07
1
7
+
CG44 RG43
RG44
• STEREO 300Hz R-channel
only → ANT
• STEREO 3kHz R-channel
only → ANT
• No signal
H001
2
QG01
10
12
1M
+ +
7
CG44 RG43
1
RG44
– 15 –
ADJUSTMENT PROCEDURE
1. Connect rms meter to pin 34 of QG01.
2. Display item ATT on screen.
3. Change data by VOLUME s/t buttons so
that the reading of meter becomes value as
close as 137mVrms.
1. Short circuit RG44 with a jumper wire.
2. Display item STVC on screen.
3. Connect frequency counter to pin 34 of
QG01.
4. Change data by VOLUME s/t buttons so
that the reading of counter becomes value
as close as 15.73kHz.
1. Unsolder the solder link SL02.
2. Display item STRF on screen.
3. Connect oscilloscope to pin 34 of QG01.
4. Change data by VOLUME s/t buttons to
minimize AC output level on scope.
5. Resolder SL02.
1. Display item WBAN on screen.
2. Connect oscilloscope to pin 35 of QG01.
3. Change data by VOLUME s/t buttons so
that 300Hz element on scope becomes mini-
mum.
4. Display item SPEC on screen.
5. Change data by VOLUME s/t buttons so
that 3kHz element on scope becomes mini-
mum.
1. Shortcircuit RG44 with a short jumper.
2. Connect 1Mohm resistor between pin 12 of
QG01 and ground.
3. Display item SAVC on screen.
4. Connect frequency counter to pin 34 of
QG01.
5. Change data by VOLUME s/t buttons so
that the reading of counter becomes value
as close as 78.67kHz.
6. Remove the short jumper and 1M ohm re-
sistor.