>
>Rich Measures wrote:
>>>Although many wattmeters do use diode detectors, they do not
>>>calculate the power directly from the rectified voltage. Instead they
>>>are calibrated from other wattmeters whose calibrations are ultimately
>>>traceable to thermal standards.
>>>
>>For PEP measurement?
>
>The calibrations are done on CW, ie under steady-state conditions.
>
>A "peak reading" power meter displays the highest value of the rectified
>voltage - in other words it senses the peak of the modulation envelope,
>to read PEP.
>
>>>
>>>Earlier, Rich Measures said:
>>>>> ? RMS is equivalent DC heating ability. For example, with a
>>>>> sine-wave,
>>>>> 200w-pk would have the heating ability of 100DC watts. .
>>>
>>>This "200w-pk" is a peak instantaneous power. Peak instantaneous power
>>>is a notion with very little physical meaning, and no practical use.
>>>Ignore it - its only power is to confuse.
>>>
>>This is essentially how the FCC measures PEP.
>
>I cannot believe that.
>
I realize this, Ian.
With a 50-ohm load, 387.3v-peak indicates 1500w PEP on the wattmeters the
FCC uses.
cheers . .
- Rich..., 805.386.3734, www.vcnet.com/measures.
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