Bill says:
>Peak envelope power (PEP) is the average power supplied to the antenna
>transmission line by a transmitter during one RF cycle at the crest of the
>modulation envelope, taken under normal operating conditions.
This is the internationally agreed definition; it comes from an ITU
recommendation, which is accepted by IEC. Strictly, only a scope can measure
it, but in practice, meters are good enough with suitable circuitry and
calibration. Since most analogue scopes are only good to 5%, it's a bit
academic............calorimetric methods are best with two equal, non
harmonically related sinusoidal tones, run until thermal equilibrium is
established in the load ( or in the inlet and outlet temperatures). That can
be cross checked with DC. But is it worth it, I ask? Tune for maximum smoke
- and then back off the drive.
73
Peter G3RZP
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