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Old 29th Dec 2019, 1:18 pm   #14
Heatercathodeshort
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Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 9,145
Wink Re: Pye television 1956 screen problem

You beat me to it David.
First you need to identify which chassis is fitted in your receiver. Pye went a bit mad at this time fitting totally different chassis in the same model with the same model number!
I have looked through my PYE manuals and discovered this one for the CW17, CW17C, CS17C, CTM17 and 17TCDL.
There are three circuits. Ref RV4A RV4B and RV4C. The differences are noted on the bottom of the circuits to help identify which chassis is fitted.

As advised, replace every wax capacitor in the frame oscillator/output stage and you should obtain a linear raster. It's my guess that you will obtain quite a decent picture after carrying out these replacements. You can then work your way through the remaining caps replacing one at a time to avoid headaches.

Take plenty of pictures as it can be difficult with these wire wrapped tags in Pye receivers to locate a connection especially if you have been disturbed half way through! Avoid the blanket approach unless you feel VERY confident.

Yes these give a first class picture with a double interlace filter, a bit like a smoothing circuit in a power supply!

Avoid the over cleaning madness before you attempt the challenge..
Regards, John.
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Last edited by Heatercathodeshort; 29th Dec 2019 at 1:30 pm. Reason: Picture addition.
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