OK, I give up, how can a wire-wound resistor be non-inductive?
One of the ads in the back of an early 1940's Radio Handbook advertises
non-inductive wire wound resistors. And, I have seen some surplus ww
resistors marked N.I. on the end. I vaguely recall that meant that the
resistore was non-inudctive for power supply purposes because some wire
wound resistors were inductive even in power supplies.
I also remember while I was in high school an engineer I knew built the 813
rig in the 1956 Handbook. It was beautiful, but it refused to work. He
finally brought it over to me because he could not fix it. It seemed ironic
than an engineer would bring it to me, since I had limited test equipment
and limited knowledge - although I did build all my own equipment and most
hams in 1959 were appliance operators, contrary to myth. I found the cause
of his problem. He was loading into a 50 ohm wire wound resistor. I
substituted the closest thing I had to a real dummy load - 2 x 150 watt
light bulbs - and it worked fine. Soon after, he gave up engineering and
became a teacher.
73, Colin K7FM
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