819 line Philips scan fault - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

murphyv310 · 22nd Oct 2006, 1:52 pm

Hello Everyone.
I was talking to David Boynes yesterday and he says that the identical set to mine is producing the same problems. It looks like either a design problem or possible conveter probs. I would like to see the set on Kat's PC converter.
Thanks all for your input
Trevor

tubesrule · 22nd Oct 2006, 2:37 pm

Hi Trevor,
The only 819 set I have is a Sharp TRP801 and I don't get this fold over issue, but I'll double check the timing parameters on the converter to make sure they are to spec. It certainly is possible that I have a timing parameter wrong. The back porch would be the most important one for an issue like this. If the video data is coming too soon and the line oscillator is still in retrace this might happen.

Darryl

22nd Oct 2006, 1:52 pm	#21
murphyv310 Dekatron Join Date: Sep 2006 Location: Kilmarnock, Ayrshire, UK. Posts: 5,422	Re: 819 line Philips scan fault Hello Everyone. I was talking to David Boynes yesterday and he says that the identical set to mine is producing the same problems. It looks like either a design problem or possible conveter probs. I would like to see the set on Kat's PC converter. Thanks all for your input Trevor __________________ Cheers, Trevor. MM0KJJ. RSGB, GQRP, WACRAL, K&LARC. Member

22nd Oct 2006, 2:37 pm	#22
tubesrule Hexode Join Date: Jul 2004 Location: Michigan USA Posts: 325	Re: 819 line Philips scan fault Hi Trevor, The only 819 set I have is a Sharp TRP801 and I don't get this fold over issue, but I'll double check the timing parameters on the converter to make sure they are to spec. It certainly is possible that I have a timing parameter wrong. The back porch would be the most important one for an issue like this. If the video data is coming too soon and the line oscillator is still in retrace this might happen. Darryl