colin: on the same note, i have a bench ps i built in 1957 lv plus hv plus
var. outputs well the xformer went out so in replacing it i checked some of
the carbon resistors in the var. voltage circuit. see below
27 k 2w = 11.86 k
20 k 1w =11.7k
12k 1w =22.7k
330k 1w =535 k
2 parallel 470k 1w =442 k
a 270 ohm 1w of the same age (1957) was still 270
a 470k 1/2 w was now 496 k
bear in mind the ps is not on all the time. just now and then for testing
and the resistors were run a rated dissp. or in most cases less.
regards hank
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