[AMPS] Network analysis of suppressors

[measures]

>
>> 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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