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Old 5th May 2021, 5:11 am   #28
ortek_service
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Location: Northampton, Northamptonshire, UK.
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Default Re: Early EPROM programmer.

I had spotted that they did use a Black case for the (Rather cheaper Menta Z80 training computer - Which I've never seen a physical one of, and only recently noticed it whilst looking at these old ads / found a review of it on the 'net): http://www.muzines.co.uk/articles/mi...ral-menta/3695
Where it's a rather similar layout to S2, but with less IC's? - and this says they even used the same case, for even more cost savings!
https://www.old-computers.com/museum...sp?st=1&c=1277
However, the Menta and the Softy-2 etc. are all in White cases, in the (1983?) ad, shown here: http://www.bygonebytes.co.uk/Softy.html
And also the one that the Cambridge CfCH might have (but no actual Dataman Documentation? as for a different Menta?): http://www.computinghistory.org.uk/d...Designs-Menta/


But I'd not originally noticed that the Softy-2 manual does have a black-cased S2 on the cover:
https://www.worthpoint.com/worthoped...mmer-307527523


However there only seems to be one 'S4.1' PCB version in these from also looking at the various pictures in the Zip file I'd linked to that CircuitBoy had posted (where one had an extra sounder-PCB fitted).

But those had 'SC' written or typed on it's 2716 firmware EPROM label - Whereas this new find has 'SB' printed on its label.
So I guess B or C were versions-letters for the S2 (rather than 3-digit number used on the S1's EPROM label)

You can just about make out the PSU on the Softy-2 Manual's cover photo.
And it doesn't seem that the Softy-2 had an on-board 5V regulator, unless the only TO220 device (a transistor labelled TR5) is used with adjacent zener to form a regulator. But this one doesn't have a heatsink (although others had a small bit of bent Aluminium)
So might be able to just apply +5V to the +5V main-rail in it (as high +25V etc programming voltage is only required to program EPROM)

If only there was a scan of the Softy-2 Manual to be found on the 'net, that's been pictured alongside the other units that have been up for sale etc. in the past. - Although, if Softy-2 was only ready-built, they may have not give an actual full schematic.

Last edited by ortek_service; 5th May 2021 at 5:17 am.
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