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Philco 118x floor model restoration
#14

thanks for the reply!

i havent checked my  multistage wirewound yet, but the 6500 tested pretty good. theres one or two other larger resistors im going to go ahead and replace with 1 or 2 watt resistors; theyre larger than the rest, and while im sure thats nothing to go on specifically, its probably also not bad either. 

so heres a question, and i think ive basically got the answer already, but please correct me where im wrong...

the schematic will often call out resistance values that are not what you find in the chassis. i figure that as long as the value you find in the chassis is within tolerance of whats on the print, you should be good to go. but why did they call out something on the print, and then when it came time for assembly they were like "aww heck with it, this ones pretty close!" 

i mean, im a machinist by trade, so i can appreciate and understand the meaning for having a tolerance, but this just seems a little strange that so many resistors would be off by a little here and there.

and what should i do when replacing resistors? for instance, ive got a .5 meg on the schematic, which is a 490k in the chassis. the resistor is sitting at .9 meg...obviously way too high. on my bench ive only got a 470k to put back in there, but thats still in tolerance. so do you just do that? do i bother throwing another resistor in series to try to bring it up a little, and if so, what should i shoot for, 490k or .5M? im sure the difference is negligible, but im also very new to this, so i dont know what i can get away with and what i should be obsessing over.

for that matter, what if i just put two 1meg's in parallel? would that mess up the circuit, or is that an acceptable fix for just not having the right resistor? 

thanks again for everyones help, i couldnt do this without you!

Brian


Messages In This Thread
Philco 118x floor model restoration - by Foose - 11-05-2017, 04:02 PM
RE: Philco 118x floor model restoration - by Foose - 11-19-2017, 03:04 PM



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