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Lostgallifreyan

Phil Hobbs wrote in
m:

Lostgallifreyan wrote:
(Hal Murray) wrote in
news
There is another dimension to consider: duty cycle. I've been told
(but don't have first hand experience) that old fashioned carbon
composition resistors are much better at pulse loads that newer
carbon film resistors.

They're also a lot better at high voltage. I'm just mentioning this
because when I used some for a HeNe supply current limit resistor, they
really impressed me. Most other things I tried eventually burned.
Basically, a solid mass is better than a film for HV, it seems.

Except for the horrible voltage coefficient. Carbon comps' resistances
decrease by about a quarter at their rated voltage. That's okay for a
HeNe, since the tube's load line is pretty steep.

Cheers

Phil Hobbs

Well that's cool cos that's about all I ever use them for.

But they were
the perfect answer in this singular case.