measures wrote:
>
>>
>>measures wrote:
>>>
>>>>The correct unedited conclusions are on N7WS's web page.
>>>>
>>>
>>>Who needs conclusions when we have the numbers Wes measured?
>>>
>>
>>For the benefit of anyone who joined AMPS since the N7WS Incident,
>>here's a short run-down.
>>
>>Wes Stewart, N7WS, tried to help resolve the disagreements about the
>>relative virtues of conventional R-L parasitic suppressors and Rich's
>>designs using nichrome. He obtained an R-L suppressor from Tom and a
>>suppressor from Rich,
>
>? Not quite. I supplied Wes with the materials and he constructed a
>suppressor that was similiar to the W8JI suppressor. Both had c. 100nH
>and 100-ohms.
>
Thanks for the correction.
>> measured the R-X properties of both types on an
>>impedance analyser, and published the results.
>>
>>The AMPS archives show that:
>>
>>* Wes strongly disagreed with Rich's interpretation of the measurement
>>data. To see how Wes himself felt about this, go to his own web page, if
>>it's still there - http://www.azstarnet.com/~n7ws
>>
>>* Rich's own interpretation was based on a total
>
>? (key word)
>
>>misunderstanding about
>>what "Rs" means.
>
>? I originally designated the suppressor resistor as Rs. This
>apparently confused some people, so now I call it R-supp.
>
People were confused because you were unaware that "Rs" always means
"series equivalent resistance". You actually believed that the Rs values
quoted by Wes *were* what you now call R-supp.
> Wes measured the Q of the two suppressors at various frequencies. At
>100 MHz, the copper-wire (W8JI) suppressor had a Q of 2.2, and the
>resistance-wire suppressor had a Q of 1.5. The difference is 46%.
>What's to interpret, Ian.?
>
Everything!
That difference simply meant that Wes hadn't made the two networks as
"similar" as he had hoped for. From his measurements, it was easy to see
how he could have made a conventional suppressor with identical Q to
yours at 100MHz. If he had done so, it would have had *lower* loss at
28MHz than your design. Wes, I and several other people pointed that
out...
>> ...but evidently that knowledge didn't stick, ......
>
> p.27, March, 1989 *QST* Magazine.
My point exactly - you have deliberately chosen to ignore everything you
might have learned since then.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
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