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CRT TV repair

Mobius-1

New Member
I have two CRT TVs one Panisonic PV-M1323-A and a Sansui TDC2075-A

My Panasonic works but has the issue as shown in the videos here and I'm guessing it's something screwy with the vhold but there's no knob or setting to adjust it so I tore it down and took images of the PCB Panasonic PV-M1323-A 13
Now my Sansui has NO power not even the light on the VHS or DVD player and here are images and some readings I took from it. The large piece which I THINK is the PSU that I circled in blue has no voltage coming out from it
Sansui
I looked EVERYWHERE for documentation and spec sheets on these two but no luck
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Panasonic:
Panasonic manual possibly here:


Possibly the large electrolytic in the PSU (reservoir capacitor) O/C, as it looks like it might be a huge hum bar.

Sansui:
The blue circled component is the switch-mode transformer, so an integral part of the power supply. Without a schematic it's difficult to make any suggestions - obviously the burnt out resistor is an issue, but what does it do, and what made it burn up (and what value is it). I would suggest seeing if it connects from switch-mode transformer to a rectifier, and if that rectifier is S/C.
 
Last edited:

Mobius-1

New Member
Panasonic:
Panasonic manual possibly here:


Possibly the large electrolytic in the PSU (reservoir capacitor) O/C, as it looks like it might be a huge hum bar.

Sansui:
The blue circled componnet is the switch-mode transformer, so an integral part of the power supply. Without a schematic it's difficult to make any suggestions - obviously the burnt out resistor is an issue, but what does it do, and what made it burn up (and what value is it). I would suggest seeing if it connects from switch-mode transformer to a rectifier, and if that rectifier is S/
Ordered a new resistor for the Sansui as for the Panasonic I wasn't sure what cap you were talking about but I circled it in red and I found these pots but not sure if they have anything to do with it. Oh and the manual shows a different model... this one seems hard to find

Also included a pic of the bottom of the PCB
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Ordered a new resistor for the Sansui

Does it go to a rectifier?, and is that rectifier short? - and how did you know what value to order?.

as for the Panasonic I wasn't sure what cap you were talking about but I circled it in red and I found these pots but not sure if they have anything to do with it. Oh and the manual shows a different model... this one seems hard to find
There's only one large capacitor :D and you've circled it.
 

Dick Cappels

Active Member
Don't touch the "Focus" or "Screen" pots, they are not where your problem is.

What you are seeing is very bad vertical linearity. In many CRT receivers and monitors there is a capacitor used to boost the voltage to the vertical amplifier during vertical retrace. The capacitor will be in the vertical deflection circuit and will be an electrolytic type. It has finally gone "open".
 

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