TC-01 Resurrection – For Easter

My Poorly Einstein! It was not a well beast.

On every boot up, I get this screen

Not sure what was causing the problem, I purchased 2 x multiplexers from eBay and removed the old ones, fitting the new ones into sockets.

The old multiplexers – SN74LS157N
New sockets with replacement multiplexers

I guess the multiplexer replacements were unnecessary. The Einstein still would not boot!
I put a call out to the 8-bit community on Facebook and a nice chap replied who suggested that it could be the video memory that is faulty.

Old 4416-15NL DRams + VDP chip

With de-solderer in hand, I attacked the 2 smaller chips and replaced them with sockets and new old stock 4416-15nl chips from eBay

New sockets, awaiting replacement chips
Amazing, the Video DRam chip replacement worked.
I now have a very stable Tatung Einstein. – Phew.

Retro Brite is the next stage, to make the keyboard and case look the part

From This
Via this. – BBlonde factor 30 and 6 hours of UK sunshine
To this. JOB DONE!

I just need to get a metal sticker for the wrist rest, then its fully restored.

Next up .. GOTEK floppy drive replacement! 🙂