As I stated, I have not tried this approach, but it may be better than
replacing terminating resistors... The idea is to put the neon in parallel
with the terminating resistor, such that when the firing voltage of the neon
is reached, it fires and conducts, thus protecting the R from over-current
and damage...
Looking in the current Mouser catalog, most neons fire around 65/90V, with
current ratings of anywhere from 300ma to 8.0 Amps. Unfortunately, a
conventional 480 ohm terminating resistor would require a power dissipation
of almost 9 watts to handle 60V continuously. Four 2K/2w resistors in
parallel should do the trick...
73- George, W4BUW
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