[Amps] resistors

[Richard]

>Rich said:
>
>>However, 1W carbon-comp resistors are max-rated at about 350V, so they 
>>slowly change value with 1000V 
>
>
>Carbon comp resistors slowly change value even when they're MIL types, 
>unused, still in MIL sealed packaging. At 1000 volts, the change is rather
>faster.
>
>I'm pretty leary about using standard carbon comps for anything these days.
>..
//  All of my carbon comp resistors met the trash-pickup one Monday after 
I did some  measurements with my Fluke DMM.

  RE  reading specs:  It is amazing that a number of Ham amplifiers use 
500pF and 1000pF 5kV doorknob caps for Tank ciruit padders which 
obviously need a cap that can handle more current.  The cap mfg's specs 
make it  clear that the 500pF and 1000pF units are intended only for 
bypass and coupling service.  Thus, to make a 400pF C-tune padder, 4, 
100pF, 5kV units are paralled on Cu plates.  The Alpha 77SX is a good 
bad-example.  

cheers.

-  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, 
www.vcnet.com/measures.  
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