Atari 65xe lifting

I’ve recieved this Atari several years ago from friend of mine (hi Agata! :-)). Upgraded it with Stereo Pokey and Ultimate 1MB, it had very yellowed keyboard (otherwise it was very nice). Few months ago I thought that I could do much better job with it, future proof it and add dvi output with stereo sound. Stereo pokey is not yet there, but everything is PokeyMAX ready (waiting for next batch).

Yellowed keyboard


This was my first attempt at deyellowing of keyboard. I had no UV lamp, so basically removed all keys and soaked them in 11% hydrogen peroxide, left them on radiator for several days in glass bottle with wide bottle neck and metal cap (you have check it periodically, and open it, because gas inside can blow it up). Normal keys turned out fine, grey ones could look better. Unfortunately end effect isn’t as uniform as I would like on them. Anyway end result looks much better than without hydrogen peroxide treatment (see the bottom of the page).

Motherboard treatment

I’ve desoldered carefully most of on-board sockets and replaced them with precision ones. Under custom chips, MMU and OS rom, so chips can be more easily replaced. Additionally there is no need to solder Ultimate1MB ribbon cables, they fit nicely into precision sockets.

Atari 65xe Motherboard with replaced sockets and capacitors

All the motherboard, connectors were cleaned with Kontakt-S and later with Kontakt-U, wiped with paper towel and left to dry.

All electrolitic capacitors were replaced with new ones, several ones were bipolar, they are hard to obtain these days (there is possibility to make those with two polarised ones, but I’ve decided not to). Not all capacitors I’ve sourced were in desired form, several axial ones were replaced with radial ones. As long as original parameters were the same it’s not big deal.

Ultimate1MB fitting

U1MB was connected as in manual, I’ve made one alteration though. I’ve desoldered cpu<->U1MB connector and soldered signals directly to U1MB board. Normal Dupont connector took too much place, so I couldn’t close the upper lid. Machine has already 64kib of memory, so ram upgrade wasn’t needed for U1MB.

Sophia2 fitting

I wanted to remove RF modulator to have cleaner video signal. Unfortunately removing modulator in XE series ends up in loss of composite signal (not that easy as in Atari 600XL), so special circuit had to be added. Hopefully x_angel from forum ( thread in polish ) sold me several PCBs, so I had only to source some SMD components, solder them in place and fit it in place of RF modulator. I’ve tested changes afterwards (with removed RF modulator and no circuit there was no video).

Small circuit soldered in place of RF modulator for composite video signal

Of course case had to be modified. In place of modulator old antenna hole I cut out rectangle big enough for dvi output and filed it a bit. Like in 600XL I’ve glued dvi connector with hot glue gun in place of old modulator. I’ve plugged Sophia2 in place of old GTIA and tested it. Unfortunately I had some problems with contacts and plugging Sophia2 onto another precision socket and then replugging it onto motherboard fixed an issue.

Prepare for PokeyMAX

Pokey sits on precision socket now and it can be replaced any time with PokeyMAX, chinch connectors were already there after old simple Stereo Pokey upgrade (,they unfortunately little too close together).

Fitted Sophia2, Ultimate1MB prepared for PokeyMAX

End result

Rear connectors

So, that’s all for today… This is my last upgrade for Atari 8-bit line. Switching to 16-bit mode, still 4 Atari’s to revamp :)….

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