I agree with Tom's arguments, just I like to add that when composition
resistors of proper power aren't available, a parallel of metal film
resistor are easy to find, withstand more power and show less inductive
reactance than a single one.
Instead of guessing about performances, in other words if a termination is
suitable or not, I think is wise to make real tests. This is not
particularly difficult even without lab instrumentation if the manageable
power of the load is the right one against own nearby TX fields or indirect
lightning strikes.
Personally I test beverages transformers and termination resistors on the
bench before installation, since my terminations are typically 10W rated
it's not a problem to feed with a TX with reduced power and see what happens
using an SWR bridge.
73,
Mauri
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