General Stuff(tm)

[stephen_usher]

Oh, and....


Happy Friday the 13th everyone! :D

[chronicthehedgehog]

Oh, and....


Happy Friday the 13th everyone! :D

:fire1:

Thanks

[stephen_usher]

Just remember to avoid walking under any black cats. Apparently it's unlucky.

[exxos]

Happy Friday the 13th everyone! :D

:hide:

[rubber_jonnie]

D'oh, you had to all say it didn't you!!!

:dizzy:

[PhilC]

I am not fixing anything today! Especially not a C128 :fire: :dizzy:

[stephen_usher]

Had another go at the black & white TV last night.

I found some more caps so 90% of the electrolytic capacitors on the board are now replaced. I also did some work on the aerial board.

At one point I had a pretty decent picture, but with some wavy interference but the sound demodulation was off on the tuner to the point where to get sound I had to detune the video quite a bit. Then I knowed the set and the RF input internal amplification seemed to massively decrease. Either I have a bad joint somewhere of there's a control which has some corrosion.

The main issue seems that the whole tuning circuit is out of alignment. The service manual says how to do all this but you need a UHF TV sweep generator and a lot of tweaking, desoldering, soldering just to do the settings.

Don't you just love analogue circuits?

[rubber_jonnie]

Had another go at the black & white TV last night.

I found some more caps so 90% of the electrolytic capacitors on the board are now replaced. I also did some work on the aerial board.

At one point I had a pretty decent picture, but with some wavy interference but the sound demodulation was off on the tuner to the point where to get sound I had to detune the video quite a bit. Then I knowed the set and the RF input internal amplification seemed to massively decrease. Either I have a bad joint somewhere of there's a control which has some corrosion.

The main issue seems that the whole tuning circuit is out of alignment. The service manual says how to do all this but you need a UHF TV sweep generator and a lot of tweaking, desoldering, soldering just to do the settings.

Don't you just love analogue circuits?

I was pleasantly surprised to see no obvious failed caps in my PYE colour TV the other week, and after a good clean it seems ok, though I may recap it down the line a bit. My uncle was a TV repair man back in the day, so it's nice to see some TV's getting TLC, but yeah, analogue circuits...

Good luck with your setup.

[stephen_usher]

Well, after 50 years all the caps were dry and out of spec. Not surprising.

Not sure how far I can get without a sweep generator though. I can use computers as a test pattern generator though, so that's OK.

[rubber_jonnie]

Well, after 50 years all the caps were dry and out of spec. Not surprising.

No, not really...

If I'm honest, I don't necessarily trust those in my PYE either, but it's for another day just now.

Not sure how far I can get without a sweep generator though. I can use computers as a test pattern generator though, so that's OK.

Yeah, they seem a bit on the expensive side that's for sure, and probably more than you'd want to pay for repairing an old B&W TV.