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Old 10th Nov 2020, 4:16 pm   #100
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 7,293
Default Re: I found it! A very sorry looking MK14.

Issue...VIcky. I think I see what you did there.

My partner has your habit of giving names to gadgets. I have to keep myself constantly updated otherwise I have no idea who or what she's talking about when she asks where 'Serena' is.

I too find it suspicious that your chip tester is failing your entire stock of 7442s and to be honest the job of that chip is to connect the cathode of each display cell to 0V in turn, which it did seem to be doing (the displays were being scanned).

At the same time, the segment-driving hardware should be outputting a pattern specific to each display cell as the 7442 / 7445 steps through them, and that's the bit which does not appear to be happening.

You were always going to have to fit a 7445 eventually, so you might as well get that over with.
SiriusHardware is offline   Reply With Quote