[Amps] Checking for IMD

[R L Measures]

On Aug 12, 2006, at 8:20 PM, Tony King - W4ZT wrote:

> Tom W8JI wrote:
>>> thread. I summarized some of their comments and included a method
>>> that Rich suggested for measuring AVERAGE IMD with another receiver
>>> and a calibrated step attenuator at <http://gs35b.com/imd.html>. Of
>>> course this method can't be used to quote specific numbers for the
>>> 3rd and 5th order products but produces an overall look at your
>>> system performance.
>
>>
>> I'm pretty sure that does not give you the average IM level Tony.
>>
>> I'll have to think about that a little bit more, but off the top it
>> seems wrong because the meter on our receivers detects peaks, not
>> average. I'm pretty sure it actually would measure the highest value
>>  of peak power contained in the bandwidth of the receiver filter,
>> assuming the receiver is perfect.
>>
>> Average makes no sense to me, since a receiver S meter is not an
>> averaging measurement device.
>
> That makes sense and it really isn't an issue of peak versus  
> average to
> me but rather a means to compare the levels

Indeed, Tony, indeed.
>>
> ...

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