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Old 1st Mar 2021, 6:59 pm   #5
Timbucus
Octode
 
Join Date: Mar 2019
Location: Barry, Vale of Glamorgan, Wales, UK.
Posts: 1,364
Default Re: The Transam Triton Personal Computer

Welcome to the forum Gerald, you may be replying to messages but, your early ones will be subject to moderation so will appear in a funny order - do not think you are doing anything wrong - after a few posts that will go away and it will become closer to real time.

As pointed out above I have been creating a modern rebuild of the Triton with old components as I was lucky enough to secure a modern reprint of the PCB. There is a small group of us over on the big Social Network that are doing so and indeed some original owners / inheritors restoring their beloved machines so plenty of help available.

Here is mine which will next need a case:

Click image for larger version

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ID:	228004 you can see it running https://www.youtube.com/watch?v=QLoXojMKH7U and with a PI loader... https://www.youtube.com/watch?v=h-l5eP4cEFA

One of the members is restoring his and documenting it on his channel starting with a good background video https://youtu.be/0cSRgJ68_tM subsequent ones cover the repair. One of the other members is a bit of an expert having created a modern respin of the board (if anyone here fancies a challenge) and also the memory expansion you see on mine which allows me to run the 7.2 HUMBUG.

I would echo the advice to not be tempted to apply power. The original circuit relies on a Zener and under specified dropper resistor - the failure of which is pretty fatal to several chips and it is likely the three big Electrolytics if not physically leaking fluid are likely leaky electrically... even to a dead short situation. The transformer is unobtainium and would likely not be too happy with that event and the failed chips will add £100 to the repair bill.

At least the main chips; CPU, CLOCK, LS154 and the Video Chips U61/69 need to be removed as they can be a bit pricey to replace. U69's presence in the Apple 1 pushes up its value... IC70 is a single use PROM which if it has failed will make the machine seem dead. IC54 is similar but, even some failed bits as Jim had will just display corrupt graphics. Certain of the EPROMs are not preserved online so again will be worth checking and securing their contents before proceeding.

That said once the power is stable if indeed as is likely it is all socketed there is no reason it cannot be restored to full glory. If you can supply some photographs of the current condition inside and out then we can asses a route to help get it going safely.

The User Group magazine you mention was called Triangle and then just the Newsletter of the Triton User Group - many are missing so if you have any some scans would be appreciated! http://www.computinghistory.org.uk/d...November-1979/
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