Not Always Impossible | Repairing an old Orange Gas-Plasma Display

In which I swap out driver ICs to get a Compaq Portable 386 gas plasma display working again. I'm pretty sure the Compaq Portable III uses the same screen. Probably a lot of portables that use a 640x400 display use one or something very similar.
These screens are Matsushita (aka Panasonic) part number MD400F640PD5
Parts I scavenged from the parts screen are:
SN751518 - PNP Open Collector outputs, used for Column driver
SN751506 - Open Drain JFET outputs, used for Row driver
Some more Compaq Portable 386 details:
alnwlsn.com/z/...

[@CuriousMarc]

Nice acrobatic repair!

[@NoPegs]

Plato display. Fun times!

[@bytesandbikes]

Great to see a few more of these surviving!😄

[@JamesPotts]

Both my 386 keyboards work perfectly, too. I guess Compaq must have used different foam than everyone else.

[@GreenAppelPie]

Demon screens.

[@IsaacMcMillan-u7i]

I'm doing the exact same repair and ran into the same issue where the chips seem fine before you take them off, but they go bad when you put them back on. Do you know any way to source these chips? Right now I'm canabalizing a compaq screen and two Toshiba screens. Also where did you get the datasheet?

[@alnwlsn]

Haven't used mine enough to see anything go bad yet. I don't know of any sources for them, but a single bad screen has quite a few (which might be bad in turn, but that's life). They are big packages though; a discrete SMD version from tiny parts could probably be made, but that would put anyone's skills to the test. For datasheets, both of my parts numbers were on alldatasheet.com. They were both TI datasheets, but it seems TI has reused these part numbers since then so if you look on Google those ones come up first.

[@ksjoet]

On my Compaq Portable III I have a very similar issue as on yours were driver number 6 from the top appear to cause all the issues on my screen. If you have one or two SN751518 that you would be willing to part with that would help massively!

[@alnwlsn]

Sure, if you're willing to cover shipping, a couple chips are yours! Use the contact email on my channel page.

[@jameslawrie7517]

How much would you charge to fix two of mine? Ill pay you to fix and recap both.