[vcf-midatlantic] Help! Stuck bit

Dean Notarnicola dnotarnicola at gmail.com
Wed Oct 9 21:54:17 EDT 2019


Hey VCF peeps! I’ve got a Briel Altair replica that has a stuck bit on the
front panel. I’ve verified that switch (bit) 5 lets me deposit a zero or
one into any given memory address. But when I go back to examine it, it
always show one regardless of the actual state of the bit. I verified that
the switch is good, the led is good, and I replaced all the 74 series
latches without effect.  There is a 220 ohm resistor in line with it that
reads 216 ohm but that should be well within spec for a 5% resistor. I
could replace it with a new 2%, but I’m not sure that would fix anything.
Anyone have any ideas why this bit always lights when I examine it? Thanks.

Dean


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