I made a mistake about 35 years ago buying some "non-inductive resistors for a dummy load. The only place they were non-inductive was at 60 Hz. The carborundums are not in the category. Joe W4AAB
I use a bank of a dozen 600-ohm 150w "Glo-bar" carborundum resistors to achieve a 50-ohm dummy load rated 1800 watts continuous duty air-cooled.
I once picked up some so-called noninductive resistors that were wirewound in two layers wired in parallel, with the wire of one layer wound in opposite direction of the other layer. They would not work in a dummy load without a series variable capacitor to tune out the reactance. I suspect that type of resistor, which may be satisfactory for the AM broadcast, might have substantial inductive reactance on the HF amateur bands. With the capacitor, mine worked OK. I doubt if an ordinary wirewound resistor could be made to work satisfactorily, since it would behave more like an rf choke than a resistor at those frequencies.
Don k4kyv ______________________________________________________________ Our Main Website: http://www.amfone.net AMRadio mailing list Searchable Archives: http://www.mail-archive.com/[email protected]/ List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
