And here is a third comment on the subject.
BOTH are partially wrong, Measures for his ideas about parasitics being
the cause of everything bad that happens.
Long before W8JI came along and declared himself the messiah of all
things some commercial and military amps used nichrome or mumetal as the
suppressor inductance. If you go back to the 90's archives I mentioned
it a few times and then gave up as a few people will not accept anyones
ideas but their own.
I personally saw the results, as strictly an observer, of a 3CV1000
military amp prototype that defied all attempts to stabilize until a
1/2" wide ribbon of Mumetal was wound around the big Globar. It then
passed all tests 2-30 mHz using a reactive dummy load to simulate VSWR's
of up to 4.5:1 of either sign.
So, before anyone goes off half cocked and believing everything they
read on the Internet please consider the above.
Carl
KM1H
----- Original Message -----
From: "Vic K2VCO" <vic@rakefet.com>
To: <Gudguyham@aol.com>
Cc: <Amps@contesting.com>; <Gary@doctorgary.net>
Sent: Tuesday, February 10, 2009 11:15 PM
Subject: Re: [Amps] Nichrome wire for suppressors
> Gudguyham@aol.com wrote:
>>
>> In a message dated 2/10/2009 10:36:09 P.M. Eastern Standard Time,
>> Gary@doctorgary.net writes:
>>
>> Anyone have a suggestion where I can find quick & easy find about a
>> foot of nichrome wire to be used in parasitic suppre
>>
>>
>> Does anyone dare answer this?
>
> Sure. The use of nichrome wire in VHF parasitic suppressors is
> controversial. A very good
> explanation of VHF stability in vacuum tube amplifiers which argues
> *against* the use of
> nichrome wire can be found at <http://w8ji.com/vhf_stability.htm>.
>
> If you want to see the opposite side, look at Rich measures' site,
> <http://www.somis.org/>. He also will sell you a kit including wire
> and the appropriate
> solder and flux to make a nichrome suppressor.
>
> Personally, I think that although many of Measures' ideas are
> useful -- I like his fast
> t/r switching circuit -- he is wrong about the nichrome and W8JI is
> right.
>
> That wasn't bad, was it?
> --
> 73,
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
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