Sony TV-700U getting audio but no video

[Alex KL-1]

I have one TV-700U working.

Besides that tv-nut said, I can add in practice, fortunately this set are not overly fussy about the V and H user controls (in the side), but anyway, for game console having a little different freq. for H, V or both, a simple readjustment makes the day.

But, maybe it have some sound or video IF misaligment; perhaps marginal to other sources, but maybe being far off for the Magnavbox. If is impossible to find a usable point using the fine tuning, perhaps this are ocurring.

BTW: my set needed a "full cap service", ie, all electros are bad. This can even influence the sync separator, since electro are involved for biasing and coupling. This makes the set fussy about the sync.

In my to-do list is some realigment for my TV-700U; the sound is a little off.

[zeno]

One caution. The service adjustments ( h-freq, V-lin, V-size ) are
very small & delicate. They also have lock tight on them often.
SO go very easy on them !
Sounds like the electrolytic caps are bad in both the Hoz & Vert.
It could also be just a dirty tuner.
BTW the fine tune is multy turn. Could be that is way off.
When you see the pix try turning it 1-2 turns CW & see what happens.
Sometimes you also need to push it in too to engage the gears.

73 Zeno
LFOD !

[matthewray2b]

May have made the mistake of fiddling with the knobs too much to begin with so I'm kind of starting with a clean slate. The Horizontal and Vertical knobs both mess with the wobbliness of the screen (the alignment?). I can get the screen almost centered then it just goes out of wack. I turned both of the knobs so that they're at the center location because that seems like roughly where the center point is. I go to adjust the horizontal frequency and I can almost get it just right but not quite.
The best I can get is the screen being slanted. I've adjusted it multiple times and the slant is always in the same direction too.

Here's a video of my fiddling with stuff so you guys can see what I'm talking about. I don't know if it's all a problem with the TV or some stuff needs to be replaced. The knobs are unbelievably sensitive to touch. Sometimes just removing the screwdriver that I am using to turn them is enough to make the image more messed up.

https://www.youtube.com/watch?v=0924Aq3syXc

[matthewray2b]

Originally Posted by Alex KL-1

I have one TV-700U working.

Besides that tv-nut said, I can add in practice, fortunately this set are not overly fussy about the V and H user controls (in the side), but anyway, for game console having a little different freq. for H, V or both, a simple readjustment makes the day.

But, maybe it have some sound or video IF misaligment; perhaps marginal to other sources, but maybe being far off for the Magnavbox. If is impossible to find a usable point using the fine tuning, perhaps this are ocurring.

BTW: my set needed a "full cap service", ie, all electros are bad. This can even influence the sync separator, since electro are involved for biasing and coupling. This makes the set fussy about the sync.

In my to-do list is some realigment for my TV-700U; the sound is a little off.

How could you tell it needed new caps? Were they just visibly bad?

[Alex KL-1]

Originally Posted by matthewray2b

How could you tell it needed new caps? Were they just visibly bad?

Due to age, some capacitors simply leaks, or lose value. Is common with electrolytics. Since this small TV uses a lot for inumerous functions, various curious symptons can occur.
Even with some "half bad" caps, the TV can be adjusted to almost normal operation, but some controls become very picky.
I have one TV-700U working and one spare (with dead CRT). One had ALL electros >5µF bad, and other had 1/3 bad. Statiscally, I bet that at least some can have problems.

If are some bad caps at same time with some RF/IF misaligment, the TV will be very difficult to use.

[matthewray2b]

Originally Posted by Alex KL-1

Due to age, some capacitors simply leaks, or lose value. Is common with electrolytics. Since this small TV uses a lot for inumerous functions, various curious symptons can occur.
Even with some "half bad" caps, the TV can be adjusted to almost normal operation, but some controls become very picky.
I have one TV-700U working and one spare (with dead CRT). One had ALL electros >5µF bad, and other had 1/3 bad. Statiscally, I bet that at least some can have problems.

If are some bad caps at same time with some RF/IF misaligment, the TV will be very difficult to use.

Are you aware of a full cap kit anywhere or should I just go through and find each one? I wasn't able to find a service manual for it online, or much info about it to begin with.

[Alex KL-1]

Originally Posted by matthewray2b

Are you aware of a full cap kit anywhere or should I just go through and find each one? I wasn't able to find a service manual for it online, or much info about it to begin with.

A kit I believe it don't exists...

I have the SAMS of this model. If you not able to find the schematic, I can take photos of it.

[matthewray2b]

Sounds good. I should probably be able to find everything I need inside. What is SAMS?

[Alex KL-1]

Originally Posted by matthewray2b

Sounds good. I should probably be able to find everything I need inside. What is SAMS?

SAMS, people from USA can explain in detail, but for short, was a North American service specialized in making own drawing schematics (generally clearer than from some brands), and, amongst other things, making a local replacement/equivalent list.

In other words. I have it's schematics and parts list.