Rich wrote
> I have never claimed that our suppressors stop parasitics. . In
> Wes'
> suppressor tests, Rich's suppressor exhibited around a 40% improvement
>
> (decrease) in parallel equivalent resistance (Rp) at 100MHz compared
> to a
> conventional suppressor. I have claimed that a decrease in VHF-Rp
> results in a decrease in VHF gain at the anode-resonance.
> >...........
>
Interesting you bring this up. You used Wes' tests many times in your
mails to the reflector, and even used to have a link on your web pages
to his web site. Interesting enough, that link has now gone, and now you
only show one graph supporting your claims. Good that there are still
search engines on the web. For those interested, the full (or should I
say real) story is at:
http://www.azstarnet.com/~n7ws/supp-2a.htm
A quote from that page:
"Some mathematical manipulation can demonstrate that shunting the
conventional suppressor with additional resistance will bring the curves
into better alignment. An additional 250 ohm resistor in parallel with
the network will cause the Rp curves to nearly overlap the nichrome
curves above about 30 MHz. Below 30 MHz, the Rp of the adjusted
conventional type will be higher than the Rp of the nichrome device. If
a parasitic suppressor functions as described by conventional wisdom,
then this should be a more desirable case."
Another quote from N7WS' web site:
"This graph compares the loaded Q of a W8JI (conventional) and AG6K
(nichrome) suppressor. Note that the HF Q for the conventional
suppressor is higher than the nichrome type. At VHF, the two types are
essentially equivalent.
In other words, unless you're selling nichrome wire, there ain't a
dime's worth of difference. If you are selling nichrome wire, then
there's about $20 worth the difference, in your favor."
This latter statement can be found on:
http://www.azstarnet.com/~n7ws/supp-3a.htm
Conclusion #1:
The effectiveness of a suppressor has nothing to do with whether you use
Nichrome or not, but is only depending on using the right combination of
R and L.
Conclusion #2;
This doesn't mean that Rich's suppressors don't work, because they might
well be the right (or even the optimum) combination of R and L.
Conclusion #3:
If you quote someone's work, make sure you quote all of it, not just the
bits that suit you.
Cheers
Gerard, AA3ES
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