05-13-2010, 04:21 PM
exray Wrote:1/2 watt would be fine. Quick math:
Power = current squared times resistance. p/n 17 would be the worst case since it carries load for all three tubes. Figure 10ma for each tube. That's far above the worst case!
So 30ma total, or .03 amps. .03 squared is .0009. Multiply that by 100. Result is .09 watts.
These resistors aren't doing any voltage dropping to speak of. Their main purpose is to provide some isolation between the stages.
GL,
Bill
Thanks for the info, I have been collecting philco's for years but have recently started electronics restoration. I service H.V.A.C. for a living and one thing I have found is that the schematics in the heat and air equip. are accurate to if it shows a conection at a certain point that wire can be traced straight to that point but in these radio's it is harder(atleast for me) to trace a conection because it may jump across 5 different terminals/conections before reaching the point of A to B that the schematic shows. But with time I am sure I will get it down. Again, thanks for the information.
Todd