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Vintage Television and Video Vintage television and video equipment, programmes, VCRs etc. |
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21st Sep 2019, 9:35 am | #21 |
Heptode
Join Date: Sep 2014
Location: Coventry, West Midlands, UK.
Posts: 518
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Re: KB WV20 Warwick
I finally felt up to having another look at this set, I do it in fits and starts as I feel exhausted all the time, I checked the 0.25uf cap (C65) and that was ok. But what I did find was that the former of L50 L51( just visible on the clip of the circuit on post 8) was broken, these coils are the cathode traps in the video stage. How someone has broken two formers on one chassis is beyond me, I don't think I have ever even broken one.
having taken the assembly off the chassis it is apparent that some of the wires are adrift. So I have to somehow glue the former together again and then hopefully will be able to reattach the wires. I have had to take the cores out to be able to try and fit it together so whatever I use to glue it has to be firm enough to take the screwing in of the cores. I am hoping that if and when I can repair this it will cure the problem I am having on the picture Steve |
24th Sep 2019, 7:12 pm | #22 |
Heptode
Join Date: Sep 2014
Location: Coventry, West Midlands, UK.
Posts: 518
|
Re: KB WV20 Warwick
Well I did manage to fix the former and reattach the broken wires. The only thing is that because of the glued former the lower core can't be screwed out to the end of the former.It hasn't though made any difference to the fault. I have replaced all but 4 resistors in the video output stage and have ordered replacements for the others and its still the same, capacitors have also been replaced. I am wondering if it could be the tube? I have noticed that if I turn the brightness up about halfway flyback lines start to appear and at full brightness they basically cover the whole screen from top to bottom this is even though I have replaced the resistors and caps in both the brightness control circuit and the flyback suppression circuit. I have run out of ideas any ideas would be welcome
thanks Steve |