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The Story of the P2
"-tick-tick-tick-." After some warming up and some clearing away the cob-
webs, this P2 bcgan giving pretty good stability. In some hours when the tempera-
ture wasn't changing much, it would hold 20 or 60 FV p-p-not bad for a unit with
perhaps 200 bV/"C. Also not too bad, considering that the trim pot had an end-to-
end range of 100 mV, so that asking it to hold 100 FV-the equivalent of 0.1 % of
span-was about as optimistic a task as anybody ever demanded of a carbon pot.
But sometimes it did a lot better than that.
However, the offset kept drifting to the left. Could it be some kind of chemical
interaction, where the RTV is changing slightly after all these years of inactivity?
After all, the P2 really is not a well-balanced circuit. Maybe the drift rate will slow
down if I do some warm-temperature burn-in?!
You never can tell. . . .
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