JI's experiments are rather limited in scope. He runs into a perfect 50
Ohm load which is rare in the real world.
Since the Mumetal method was approved by the US government it does make
it valid and acceptable.
Carl
KM1H
----- Original Message -----
From: "David Goncalves" <davegoncalves@gmail.com>
To: <amps@contesting.com>
Sent: Wednesday, February 11, 2009 10:56 AM
Subject: Re: [Amps] Nichrome wire for suppressors
> W8JI does make arguments with supporting analysis and clearly designed
> experiments. More than you see from some others.
> The amp you mention being tamed by the suppressor proves that THAT
> particular suppressor helped THAT particular amp. Nothing more.
>
> David Goncalves
> W1EUJ
>
>
> On Wed, Feb 11, 2009 at 10:22 AM, Carl <km1h@jeremy.mv.com> wrote:
>
>> 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
>> > http://lists.contesting.com/mailman/listinfo/amps
>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
>
>
>
> --
> David Goncalves
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
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