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Old 10th Nov 2020, 8:04 pm   #102
Buzby123
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Join Date: Oct 2011
Location: Culcheth, Cheshire, UK.
Posts: 637
Default Re: I found it! A very sorry looking MK14.

Tried testing chips as 7442 and 7445, all test bad.

Lashed up a breadboard, inserted 7442, wiggled d0-d3, ten outputs changed as expected.

So from that we can deduce my TES200 is not as clever as it should be.

TES told me all the other TTL parts are OK, and I'm tempted to believe that, as when I scope the board all the pins I expected to wiggle are wiggling.

But still no nearer to getting Vicky running

The only chips not tested yet are RAMs and ROMs.

Cheers,

Buzby
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