> 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. 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. The nichrome
suppressor tested had a lot more inductance.
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.
73, Tom W8JI
w8ji@contesting.com
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