[Amps] Need some 220K 2 watt carbon resistors

Peter Chadwick g3rzp at g3rzp.wanadoo.co.uk
Mon Mar 27 04:05:28 EST 2006


Gary said:
>If you are using them for cap equalizers in a power supply I would use metal
film resistors instead. The carbon resistors drastically change value.<
220K could be a bit high for series capacitor equalisers, depending upon the leakage current of the capacitor. Even if they're low enough in value (I'd use a rule of thumb of resistor current equals 5 times rated max leakage current), I agree with Gary. Use MOX instead. Carbons drift like Kon Tiki. 
I had some packs of resistors. A MIL Spec, NATO part numbered 4k7, 5%, 1/4 watt, carbon comp resistor, packed in a sealed polythene bag in August 1963 measured, when taken out of the bag 42 years later, 22% high.
73
 
Peter G3RZP


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