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Missing b, c and d for all digits.
Simple fix? Ideas?
(07-25-2018 09:52 PM)bakerjp Wrote: [ -> ]Missing b, c and d for all digits.
Simple fix? Ideas?

Could be a faulty anode driver chip or may be corroded/broken connections between the LED display and this chip.

I'd check the keypad/display PCB first.


Or possibly a bad solderjoint on an inductor array or driver chip.
I thought that since the error was so "definite" somebody
(who understands the drive logic more than I do) could
determine the exact cause. Missing the same segments on
all digits to me indicates a single problem. But I might be
wrong about that. And the problem may be beyond repair.
I've read articles about this from Alex Knight, Joe Rigdon
and Tony Duall but my tools are basic; I'm an engineer
but not an electrical engineer. I do miss my calculator, though.
I've been using it for more that 30 years.
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