Hi, All, I'm in the middle of resurrecting a Static PET board (that I got last year from MH Stein in (pre-warned) sad shape). I don't have an original PET chassis at the moment, but I do have several enclosures for 2001N/3032 16K/32K PET boards (pre-CRTC). The enclosure I'm working on has a monitor that works perfectly with the 3032 board Anders Carlsson sent to me at Pole. When I plug in the Static PET board, I get characters, but not with the same "spread" across the CRT. I see 25 rows, but they are about half as tall as I'd expect (with large blank spots above and below). I do not, however, "see" 40 columns. I see more like 25-30 columns, then the brightness of some of them suggests to me that the remainder are "folded" under the visible ones - a common problem back in the day with wonky video. The chars are all sharp and stable - no tearing, no walking, no wobbling - just not 40x25 filling most of the tube (unlike the perfect view with the 3032 board). There are only two potentiometer adjustments on the monitor board - brightness and V.Height. Both do the expected thing. I can crank up the height with the 2001-8 installed, but then the 3032 display is way too "tall". I can't fix the width or the H.Pos or whatever it is that is causing the issue with the columns. I would expect that if there were a severe problem with the video, I'd get sync problems or tearing or snow or pixel garbage. There's none of that. I've looked around a bit, but the diagnostic information I've found stops before the component level. Does anyone know of any in-depth video repair info? I can't imagine there's a problem with the video board since the 3032 display is flawless - am I wrong in thinking that the video outputs from the 2001-8 and the 3032 are compatible if not identical? Does anyone recognize these symptoms? Has anyone done chip-level debugging of the video circuit on a pre-CRTC PET? I have the schematics, naturally, but since so much works, I'm not sure where to start. Thanks for any suggestions. -ethan Message was sent through the cbm-hackers mailing listReceived on 2009-09-30 03:00:04
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