>
>Hi Peter,
>you wrote:
>> I guess my objection is to taking a technical term that has a definition
>> and then simplifying without (as Ian ended up doing) ensuring that the
>> simplification and the situation of its applicability is spelled out.
>>
>> Supposing that for some reason amateurs started using OFDM with M-ary QAM.
>> You could well end up on the low bands with the PEP existing for only one
>> cycle of RF; this certainly happens at the base band. Thus the definition
>> is generally correct, while the application allows latitude. But unless
>> one recognises that this latitude is not generally applicable, it easily
>> leads to misunderstanding.
>
>
>That's right Peter. I fully agree.
>
>If you are using a wider bandwidth due to amplitude changing rapidly,
>the meter has to be designed to respond to the more rapidly
>changing envelope.
>
>> Like bit freaks and 'bandwidth'!
>
>> For all practical purposes, the assumption for amateurs at the moment is
>> valid. And the fundamental power measurement as I think it was you that
>> said, is the bomb calorimeter. Can you see the sweep tube linears running
>> for long enough to reach thermal stability in the calorimeter??
>
>That's why we calibrate the meter against the calorimeter, and then
>read the meter.
>
? Tom: The fly in the ointment is the peak detector. You can not
calibrate a peak detector with a bomb-calorimeter. In college physics
lab, the bomb-calorimeter I used took close to a minute to settle down.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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