Larry W7IUV asks about power meters.
For info:-
European equipment standards for the purposes of Type Approval measurements,
made in certified laboratories which have measurement capability traceable
to national standards, call for conducted RF power measurements to
+/-0.75dB. That's between 841.5 and 1189 watts indicated for 1 Kw actual.
Admittedly, that's the total measurement uncertainty allowed, but to even
get to that measurement uncertainty too easy. Factors that need dealing with
are the losses (and mismatch losses) of connectors, error in the assumed
load impedance, and losses (and mismatch losses) in cables - which you
cannot ignore even at HF if you are doing a proper measurement uncertainty
calculation.
Which is something I don't do if i can possibly avoid it, 'cos it's too much
like hard work.
73
Peter G3RZP
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