SLV-D900E, SLV-D900G (serv.man2) - Sony VCR Service Manual (repair manual). Page 9

◆ Remove the DECK and remove the FFC Cable (Deck to Main PCB FFC cable), and replace it with an 35-P

extension cable (at least 30cm long).
Place the Deck on a flat horizontal position.

◆ Open the LD solderland short. (See Fig. 3-10).

◆ Connect an Oscilloscope to the Envelope Waveform Test Point (See Ttable 3-6).

◆ Connect Power, Open the Tray and Play the TDV-533 Disc, Chapter 14. 

◆ Adjust the Screws “A” and “B” (See Fig. 3-6) using a Hex screwdirvier until you obtain a Flat Waveform and 

the picture is stable.
Then, go to Chapter 1 and make sure the Waveform is Flat here as well.
If not, you have to go back to Chapter 16 and adjust again. 
If you cannot obtain a Flat waveform, then the unit is defective.      

: The Deck must be in a horizontal position.

Use both “A” and “B” screws to adjust, but mostly “A”.

Typical Waveform before Adjustment

Waveform after Correct Adjustment

Fig. 3-9 Envelope Waveform