>
>> What W8JI probably meant to say (and I *did* say, at that time) was that
>> the use of nichrome in the suppressors made more difference to the Q at HF
>> than it did at VHF. From N7WS's measurements, that was totally beyond
>> dispute.
>>
>> This would mean that for the same degree of effectiveness in suppressing
>> parasitics at VHF, the losses in the nichrome suppressor at HF would be
>> higher.
>
>
>That's right Ian.
>
>The primary advantage of nichrome in a suppressor is it lowers the
>HF Q more than it lowers the VHF Q.
>
>On amplifiers with HF parasitics, that's a good thing.
[chortle]
>On amplifiers
>with VHF parasitics, it doesn't mean a thing. A conventional R/L
>suppressor would do just as well at VHF with only a minor change.
>
>By the way, the nichrome suppressor submitted in the test was
>nothing like Rich's normal suppressor that he sold.
Rich did not submit a parasitic suppressor to Wes, N7WS. . Rich sent
Wes the needed materials and Wes constructed the parasitic suppressor he
used in the tests. Wes' nichrome suppressor had approx the same values
of R and L as your A:-80 suppressor.
>suppressor tested had a lot more inductance.
Our 8877 and 8166 suppressors typically have less than 1/3 the inductance
we recommend for a 811A vhf suppressor.
>
>If you compare Rich's normal suppressor with a stock AL-80B
>suppressor the stock AL-80B suppressor provides lower VHF Q
>than the Measures suppressor.
? In tests perormed with a Hewlett-Packard Model 4191A RF Impedance
Analyzer, your copper-wire suppressor had a Q of 2.2 at 100MHz. The
nichrome-wire suppressor had a Q that was 46% lower. .
>
cheers.
BTW, I feel that much could be resolved here if we discussed your post of
28 Nov., 1996. Why have you never ever mentioned this post?. I think
your idea of a specific suppressor analysis using AC Circuit Analysis is
a very excellent idea.
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