I have a perfectly good HP-8590A (Ser No 2618AXXXXX) that has an absolutely dead display. (Another display works perfectly in it.) I don't have any of the complex software or hardware problems a lot of other guys describe - but I still can't see it!
I've poked around in it - looked at the usual suspects (dried out/leaking aluminum electrolytics..etc) and nothing yet.
I've had pretty good luck repairing the Panasonic TR-60S1A monitors used in some 8590A's, but this unit uses a more complex display. The display has a tag "Omni Vision; Glendale Heights, IL P/N LP0615EVC", with some addition numbers that are probably Lot or Date codes. There is a tag on the chassis "Hewlett Packard P/N 2090-0514". I have not found any support data for this particular monitor.
Omni Vision has disappeared without a trace - no lingering artifacts hiding on the internet.
Any help with a schematic or manual?
I've poked around in it - looked at the usual suspects (dried out/leaking aluminum electrolytics..etc) and nothing yet.
I've had pretty good luck repairing the Panasonic TR-60S1A monitors used in some 8590A's, but this unit uses a more complex display. The display has a tag "Omni Vision; Glendale Heights, IL P/N LP0615EVC", with some addition numbers that are probably Lot or Date codes. There is a tag on the chassis "Hewlett Packard P/N 2090-0514". I have not found any support data for this particular monitor.
Omni Vision has disappeared without a trace - no lingering artifacts hiding on the internet.
Any help with a schematic or manual?
There is a possibility (I can't verify this) that the Omni Vision display was not an HP-8590A display - it was used in the later 8590's, but maybe not the "A". The unit I have has had the display replaced.
Two things make me suspicious:
A. The screen has a burned-in imprint "SRQ 140 Ref Fault" (or to that effect - I don't have the CRT in front of me) This is not an error message that the 8590A can generate - so that points to the display having been in another model for a long time.
B. Once I got the display working (although badly), it was way out of horizontal sync. The Horizontal Hold control would only barely stop the display from rolling. I found documentation for the display (Panasonic and Omni Vision) in an ArtekMedia CD-ROM support manual (08590-90008). The Omni Vision manual - although sketchy - seems to indicate that the Omni Vision display was intended for 15.75 KHz horizontal sweep, not the 19.2 KHz of the 8590A. This would explain why the display rolled so badly and had limited adjustment margin. Reselecting a capacitor will probably cure this - if anything is ever that simple. Later versions of the 8590 used the standard 15.75 KHz horizontal sweep - go figure - it probably seemed like a good idea at the time.
C. Oh, by the way - the Panasonic and Omni Vision displays use different CRT's - same size - different pinouts. They don't interchange. If you look hard enough (think eBay) and get lucky, Panavision CRT's can be found in green or white phosphor, Given the choice, I'd get white for a replacement. Omni Vision CRT's seem only to be available in green - about $220 US if you find them..
So far - it's still been a worthwhile project.