Sony SLV-495 - Playback Level Check (MA-289 Board); AUDIO SYSTEM ADJUSTMENT. -R-S-Ss:s:sessssssetesseseeeess; AF Switching Position Adjustment (MA-289 Board)

2-4-6. Playback Level Check (MA-289 Board)
[Check Method]
1) Check that the playback level satisfies the specified value.
White (100%)
~~ H Se
Fig. 7-2-9.
2-5. AUDIO SYSTEM ADJUSTMENT
* For the adjustment of the audio system, perform in the SP mode
if there is no special notes. Use the alignment tape.
¢ Adjust both L-CH and R-CH (SLV-675HF/676HF/685HF/695HEF/
L60HF/L70HF/X6HF).
[Connecting Instruments]
Audio line input
Audio line output
Audio level meter
Audio oscillator
600Q
Attenuator
(Feed signals to both L and R channels at the same time.)
Fig. 7-2-10.
¢ Hi-Fi Audio System Adjustment (SLV-675HF/676HF/685HF/
69SHF/L60HF/L70HF/X6HF)
Perform the adjustment setting the switches and controls on the
following positions if there is no special indications.
CHANNEL
CHANNEL
*1) Set by remote commander
2-5-1. AF Switching Position Adjustment
(MA-289 Board)
[Adjustment purpose]
To adjust the link of the A-ch and B-ch of the tape playback outputs.
If this specification is not satisfied, the noise will increase and
cracking sounds will be produced.
ae
Alignment tape: SP color bar portion
Measurement point CH1: CN341 pin @ (AF ADJ)
sCH2: CN261 pin @ (RF SWP)
Oscilloscope
Specified value No dropouts in the RF signal
[Adjustment Method]
1) Short-circuit between JS401 and ground on MA-289 board for
about 1 second to activate the RF switching position adjustment
mode.
Check that “ADJ” is indicated on FL display.
Press the REC button to activate the AF switching position
adjustment mode.
Using the channel + and — buttons, minimize a chipped portion.
At this time, confirm that a noisy sound is not heard.
Press the PAUSE button.
Press the EJECT button TAPE SPEED
CH2
RF SWP
(CN261 PIN @)
2)
3)
4)
5)
6)
pa a
Should be minimized
RF signal dropout
Fig. 6-2-11.