K4XL:
> One point that has been discussed rather extensively on the reflectors,
on the web and in print is the size and composition of the terminating
resistor. Generally, a 2 watt carbon composition resistor is recommended.
Although a carbon composition resistor is noninductive, it has very
poor peak surge survivability compared to ceramic composition resistors
like the Ohmite OY series. I used carbon comps for many years and had
to replace them regularly after they disintegrated with nearby (not even
direct) lightning hits. Since converting to ceramic composition resistors,
I don't recall replacing any. There is no 75 ohm value in the OY series
but 68, 82 and 150 (for 2 in parallel) are available. 2 150s in parallel
would give 4 watts dissipation and would probably last forever unless you
got a direct lightning strike.
http://tinyurl.com/cf54jx
73, Bill W4ZV
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