While we're delving into glitch resistor design theory, how about some
practical advice? Before replacing the plate choke, I'm going to install a
glitch resistor in the LK550 I've been working on. KM1H suggests a 15-ohm
25W enamel wirewound. I found what appears to be a suitable part from
Newark, an Ohmite 02F2280 ceramic core wirewound resistor with a flame
resistant vitreous enamel coating. It's one of those tubular types. There's
a mounting bracket available that appears in the drawing to be a piece of
metal that goes through the hollow tube of the resistor and has mounting
tabs at both ends. It looks like the bracket will hold the resistor up off
the chassis by at least 1/4", positioning the solder lugs straight up. It
looks like a nice way to install the resistor, but is there any problem with
using this type of bracket? Does it hold the resistor rigid so that it won't
roll around? If it's not suitable, what alternative mounting methods are
popular for this type of resistor when used for glitch protection?
What's the typical result of a high-current failure in a resistor like this?
Does it come apart in such a way that the lug soldered to +HV could come
loose and contact the chassis or short to the chassis through the bracket?
73, Dick, WC1M
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