Sony TV overscanning

[pentium]

Damnit, no!
Everything seems to be breaking down on me now. Anyways, today out of the blue while I was browsing the net on my PS3 (the last computer that I still have running) the tv started to overscan. It was not much but it forced me to drop my resolution so that I could see my scrollbars again and now I'm getting a buzz through the audio. The tuner packed up on it last year and I have been using it as an S-video monitor for my home theater ever since. It's a 27" Sony tv (rather not pull the thing off the shelf to read the model off the back but it does have PIP and front inputs) if that is any help.

[Wizard]

Re: Sony TV overscanning

Width or height?

27" sony TVs are FAMOUS for bad solder joints. FIX IT NOW or that horizontal transistor go dead and shot the power supply if that one uses seperate PSU.

Cheers, Wizard

[pentium]

Re: Sony TV overscanning

I had a feeling it was a cold joint issue after letting the TV cool down for a while and turning it back on to find the problem gone until it warmed up. I'll tear it open tomorrow and go over it with the iron but this looks like a goox fix. As for the tuner....I still wish I could get that to work. I would rather play my Atart 2600 on this and not my Performa 5200 (it has a tuner installed).

[weirdlookinguy]

Re: Sony TV overscanning

Resolder any and all joints around the flyback, the HOT, the transformer near the HOT, and anything heatsinked. I had a Sony monitor go out because the transformer feeding the HOT had cold joints.

[Wizard]

Re: Sony TV overscanning

NOW or leave TV unplugged till you get around to it to fix.

Cheers, Wizard

[pentium]

Re: Sony TV overscanning

After a lot of grunting and straining to get tv into the shop it has been fixed. It seems better now.

[Wizard]

Re: Sony TV overscanning

did u do everything in horizontal circuits including the horizontal driver circuit (that grey box transformer) and coils? Also the one vertical IC pins.

HAVE a helper to move that damn TV.

Cheers, Wizard

[kc8adu]

Re: Sony TV overscanning

that set is a 2 person move.
that is unless you want a destroyed back.
as for the solder joints there will be a ton of them.make sure you get them all before running it any more.
as a bonus if you pull the tuner and i.f module you will find even more busted joints esp on the grounds to the can.
do it right the first time or there will be a bunch of parts to replace when it goes BANG!

[Wizard]

Re: Sony TV overscanning

kc8adu is right. Interestingly, I haven't yet to see bad tuner due to solder.
But IF module yes in very old Sony sets.

Sony made awesome tuners that can pull in real weak signal.

MX048 or something like that is PRICY. Especially those that have two transistors in one package. What on earth what Sony was thinking? :P

Cheers, Wizard

[pentium]

Re: Sony TV overscanning

I went and soldered whatever I could that looked like it was likely to have a cold joint. The more high voltage stuff was also done after it was discharged using a ground lead, a resistor and a screwdriver (and me wearing a glove because I got zapped once before).