20-06-2016, 05:19 PM
Mikey405 has now given me a scan too. It's no better than the one on Elektrotanya.
As far as I can see, all the logic stuff is working fine but the video levels are pretty low. I'll start by checking the PSU voltages, then have a nose around the Y, R-Y and B-Y generation. I've already got the PAL coder much better aligned just by tweaking.
The signal is pretty crude. There's no interlace and no attempt to lock subcarrier to line scan. That would be pretty pointless without interlace. The common Labgear generator of slightly later vintage uses TTL chips. It crudely divides down subcarrier to make H and V which results in colour bars looking evil on a monochrome monitor. Again not interlaced.
As far as I can see, all the logic stuff is working fine but the video levels are pretty low. I'll start by checking the PSU voltages, then have a nose around the Y, R-Y and B-Y generation. I've already got the PAL coder much better aligned just by tweaking.
The signal is pretty crude. There's no interlace and no attempt to lock subcarrier to line scan. That would be pretty pointless without interlace. The common Labgear generator of slightly later vintage uses TTL chips. It crudely divides down subcarrier to make H and V which results in colour bars looking evil on a monochrome monitor. Again not interlaced.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
