24-08-2017, 04:22 PM
I'm quitting today while I'm ahead. Friends coming for dinner this evening so much kitchen activity and I ought to be helping a bit.
I need to wean the LTB and EHT off their external PSUs. Once I've got a fair looking picture I can find out why there's no colour. Absolutely nothing when I turn up the saturation. The decoder is all discrete and pretty accessible. I don't see any problem getting it to work. Famous last words.
Funny thing is that I've designed a number of PAL coders using nothing more complex than 1496 modulators and a bit of CMOS logic. I've nver done a discrete decoder, for the one design I did that needed an analogue one I used a Mullard telly chipset. Beyond that I've used digital decoder chips such as the Philips SAA7111. The more modern of these chips do an astonishingly good job. I've not used it myself but the TVP5150 used in the Aurora SCRF is excellent. Composite video in, 8 bit digital component video out, complete with good comb filtering and minimal artefacts.
I need to wean the LTB and EHT off their external PSUs. Once I've got a fair looking picture I can find out why there's no colour. Absolutely nothing when I turn up the saturation. The decoder is all discrete and pretty accessible. I don't see any problem getting it to work. Famous last words.
Funny thing is that I've designed a number of PAL coders using nothing more complex than 1496 modulators and a bit of CMOS logic. I've nver done a discrete decoder, for the one design I did that needed an analogue one I used a Mullard telly chipset. Beyond that I've used digital decoder chips such as the Philips SAA7111. The more modern of these chips do an astonishingly good job. I've not used it myself but the TVP5150 used in the Aurora SCRF is excellent. Composite video in, 8 bit digital component video out, complete with good comb filtering and minimal artefacts.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
