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[Amps] PARASITICS AND fILAMENT SAG

To: <amps@contesting.com>
Subject: [Amps] PARASITICS AND fILAMENT SAG
From: "Edwin Karl" <edk0kl@centurytel.net>
Reply-to: edk0kl@centurytel.net
Date: Mon, 28 Aug 2006 09:13:53 -0500
List-post: <mailto:amps@contesting.com>
Gentlemen-

It would seem that someone should call the ASPCA on this
discission/argument.
That's for beating a dead horse.

I joined this thread several months ago to seek information regarding
amplifiers.
This argument as restated the discussion so much my head hurts. It takes
meaningless bits and bytes to convey and again nothing is new.

Whether or not one supressor works the same way or not dosen't matter. They
both seem to work. End of discussion.

If you want to reargue, visit the history mentioned
in an earlier trhread and just read what's there, written 11 years ago.

Just please STOP THE MADNESS.

ed K0KL


-----Original Message-----
From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
Behalf Of amps-request@contesting.com
Sent: Sunday, August 27, 2006 4:35 PM
To: amps@contesting.com
Subject: Amps Digest, Vol 44, Issue 93


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Today's Topics:

   1. Re: Parasitics & Filament Sag (Tom W8JI)
   2. Re: Parasitics & Filament Sag (Mike Sawyer)
   3. Re: Parasitics & Filament Sag (John Vickers)
   4. Re: Parasitics & Filament Sag (Will Matney)
   5. Re: Parasitics & Filament Sag (Mike Sawyer)
   6. Re: Parasitics & Filament Sag (Tom W8JI)
   7. Re: Parasitics & Filament Sag (Joe Subich, W4TV)
   8. Re: Parasitics & Filament Sag (Tom W8JI)
   9. Re: Parasitics & Filament Sag (Scott Manthe)
  10. filament forces                          TSPA (John T. M. Lyles)


----------------------------------------------------------------------

Message: 1
Date: Sun, 27 Aug 2006 14:18:12 -0400
From: "Tom W8JI" <w8ji@w8ji.com>
Subject: Re: [Amps] Parasitics & Filament Sag
To: "Mike Sawyer" <w3slk@uplink.net>,   "Joe Subich, W4TV"
        <w4tv@subich.com>, <AMPS@CONTESTING.COM>
Message-ID: <023a01c6ca05$30995440$640fa8c0@radioroom>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
        reply-type=original

>    Personal cheap shots do nothing to bolster your
> arguement, Joe. As a
> matter of fact it demonstrates weakness.

Mikey,

I don't Joe was the first to cast that stone. Why be so
rough on him?

73 Tom





------------------------------

Message: 2
Date: Sun, 27 Aug 2006 14:51:11 -0400
From: "Mike Sawyer" <w3slk@uplink.net>
Subject: Re: [Amps] Parasitics & Filament Sag
To: "Tom W8JI" <w8ji@w8ji.com>, "Joe Subich, W4TV" <w4tv@subich.com>,
        <AMPS@CONTESTING.COM>
Message-ID: <004501c6ca09$c5a52a10$46ec9341@D9PBT931>
Content-Type: text/plain;       charset="Windows-1252"

You gotta be kidding me?!???
Mike(y)
W3SLK
----- Original Message -----
From: "Tom W8JI" <w8ji@w8ji.com>
To: "Mike Sawyer" <w3slk@uplink.net>; "Joe Subich, W4TV" <w4tv@subich.com>;
<AMPS@CONTESTING.COM>
Sent: Sunday, August 27, 2006 2:18 PM
Subject: Re: [Amps] Parasitics & Filament Sag


>    Personal cheap shots do nothing to bolster your
> arguement, Joe. As a
> matter of fact it demonstrates weakness.

Mikey,

I don't Joe was the first to cast that stone. Why be so
rough on him?

73 Tom





------------------------------

Message: 3
Date: Sun, 27 Aug 2006 14:49:49 -0400
From: "John Vickers" <wa4tt@nlamerica.com>
Subject: Re: [Amps] Parasitics & Filament Sag
To: <AMPS@CONTESTING.COM>
Message-ID: <008901c6ca09$93cd0080$813cddd1@u3s8z8>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
        reply-type=original


----- Original Message -----
From: "Mike Sawyer" <w3slk@uplink.net>

>    I used nichrome and they worked. It was the only substitution made. The
> original suppressors were only in the amp for a short time (two weeks in
> intermittant operation). So it sounds to me that there is some merit to
> what
> Rich is saying.

I believe you said this was a pair of 813's. I still have one I built in
1965 running 3 813's and its never had an anode suppressor in it. Just a
wide copper strap from the plate choke (homebrew) to the tubes. Never had a
problem with parasitics. Used on 80, 40, and 20 m. Would run it with 1, 2,
or 3 tubes by just unplugging them and left the strap hanging. They were all
mounted in a straight line so plate lead was excessively long.Certainly
wasn't due to my engineering prowess--- was only 15 yrs old at the time. In
my case--- I didn't need *any* suppressor. In your case you did. It would be
beneficial if you had figured out WHY.
73, John WA4TT



------------------------------

Message: 4
Date: Sun, 27 Aug 2006 15:03:00 -0400
From: "Will Matney" <craxd1@verizon.net>
Subject: Re: [Amps] Parasitics & Filament Sag
To: gm3sek@ifwtech.co.uk, amps@contesting.com
Message-ID: <200608271503000700.0252BC65@outgoing.verizon.net>
Content-Type: text/plain; charset=us-ascii

I took a look at the alt.amateur-radio.homebrew discussion, and it didn't
look like Wes
was that mad at Rich, he just did the experiment. He also said he couldn't
get to the
page that Rich had posted at the time to see what he had put up for some
reason. Also,
the old link to the experiment that Wes done is no longer valid of course.
The files that
Wes has are hosted by Danny Richardson, K6MHE at the link below. I didn't
see the
experiment in question saved there, or it's titled something I didn't figure
it to be. I would
like to see the experiment he did with the two supressors and read what Wes
had to say.
I did see in the group discussion that Wes said he didn't think the
measurements of RP
was the same thing that Rich meant. Anyhow, if anyone has the whole
experiment that
Wes had done saved, I would enjoy the read.

Link;

http://www.k6mhe.com/n7ws/

Best,

Will

*********** REPLY SEPARATOR  ***********

On 8/27/06 at 8:22 AM Ian White GM3SEK wrote:

>R L Measures wrote:
>>> N7WS made independent measurements of this.
>>
>>N7WS, Wes, was the man who single handedly ended the grate parasitics
>>debate between Tom and me by measuring the Q and parallel-equivalent R
>>(Rp) of a conventional parasitic suppressor and that of a low VHF-Q
>>parasitic suppressor -- And publishing the results without first
>>consulting with Tom. The results:
>>http://www.somis.org/Rp-comp.html
>>
>
>:
>
>Rich gives only one part of the story. For the information of relative
>newcomers, "let the record show" the other part as well:
>
>N7WS categorically disagreed with Rich's interpretation of his
>measurements. He considered that Rich had misused the data in his web
>pages.
>
>Although N7WS cannot prevent Rich from re-publishing his own
>interpretation of the measurements, Wes Stewart does not wish to be
>associated in any way with Rich's web page.
>
>
>
>--
>73 from Ian GM3SEK
>http://www.ifwtech.co.uk/g3sek
>
>_______________________________________________
>Amps mailing list
>Amps@contesting.com
>http://lists.contesting.com/mailman/listinfo/amps





------------------------------

Message: 5
Date: Sun, 27 Aug 2006 15:07:00 -0400
From: "Mike Sawyer" <w3slk@uplink.net>
Subject: Re: [Amps] Parasitics & Filament Sag
To: "John Vickers" <wa4tt@nlamerica.com>, <AMPS@CONTESTING.COM>
Message-ID: <005801c6ca0b$fad630b0$46ec9341@D9PBT931>
Content-Type: text/plain;       charset="Windows-1252"

Snip> I didn't need *any* suppressor. In your case you did. It would be
beneficial if you had figured out WHY.
73, John WA4TT

    John,
    That's a good point. As a member of the "design team", (I say that
tongue in cheek), that they were installed as a preventative measure. The
plans were copied from 'tried-and-true' designs. It would have been great to
have access to the different network analyzers, spectrum analyzers, and
other 'hi-tech' test equipment but it simply wasn't available. I remember a
term applied to things we could not explain with the tools at our disposal:
PFM. Even though we firmly knew that somewhere there was a logical
explanation.
Mod-U-Lator,
Mike(y)
W3SLK



------------------------------

Message: 6
Date: Sun, 27 Aug 2006 15:06:56 -0400
From: "Tom W8JI" <w8ji@w8ji.com>
Subject: Re: [Amps] Parasitics & Filament Sag
To: "Paul Christensen" <w9ac@arrl.net>, <amps@contesting.com>
Message-ID: <024801c6ca0b$fe24e680$640fa8c0@radioroom>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
        reply-type=original

> At one time, Emtron offered one of their early amps with
> Nichrome
> suppressors.  I do not know if they found some rational
> reason for changing
> More plausibly, they simply did not want to get "caught
> up" in the
> nonsensical debates.
>
> If you're a manufacturer, would you really want to be
> spending all your time
> on the phone defending your use of Nichrome as a result of
> all the
> destructive discussions when you've got a business to run?

Actually Paul Hrivnak of Vectronics, when he was convinced
the glass in Chinese 3-500's was melting from parasitics,
included a nichrome hairpin in his single 3-500Z amp.

The amp kept melting holes in the glass of the tubes just
the same as it did without the nichrome.
So Emtron wasn't the first.

We actually looked at nichrome about 20 years ago at
Ameritron and even tested some amps set up that way. We
found no difference at all except a decrease of ten meter
efficiency.

Nichrome suppressors don't bother me one way or another so
long as they don't cause a problem, although I'd probably
never use one myself. The only reason I wouldn't use one is
the hairpins actually measure to have more VHF Q than the
conventional suppressors when in the circuit. Once you use
multiple turns instead of a hairpin, you can make a
conventional suppressor that has more effect at VHF and less
effect at HF. Why hurt 10 or 15 meters when it isn't
necessary?

The only harmful effects out of all of this is the setback
in people actually understanding what causes problems, and
harmful suggestions like installing resistor grid fuses and
the bad advice telling people to remove electronic
protection systems. Bad advice like that is a major problem.

73 Tom




------------------------------

Message: 7
Date: Sun, 27 Aug 2006 15:15:07 -0400
From: "Joe Subich, W4TV" <w4tv@subich.com>
Subject: Re: [Amps] Parasitics & Filament Sag
To: "'Mike Sawyer'" <w3slk@uplink.net>, <AMPS@CONTESTING.COM>
Message-ID: <004501c6ca0d$1f9e9530$0b80a8c0@laptop>
Content-Type: text/plain;       charset="Windows-1252"


Mikey,

>     Personal cheap shots do nothing to bolster your
> arguement, Joe. As a matter of fact it demonstrates weakness.

That is nothing more that rich has been doing to other participants
of the Amps list for years.  Frankly, his constant misrepresentation
of Wes Stewart's work and work by others is far more "cheap."

Ever wonder why staff from none of the amateur manufacturers will
participate here?  Ever notice that people like Dick Erhorn, Dick
Frey, Wes Stewart, Carl Huether, etc. no longer participate here?
It's because they gave up after the constant abuse from Rich Measures,
his refusal to listen to real engineering that failed to support
his junk science and his constant misrepresentation of the truth.

>     I used nichrome and they worked. It was the only
> substitution made. The original suppressors were only in the
> amp for a short time (two weeks in intermittant operation). So
> it sounds to me that there is some merit to what Rich is saying.

If you used the full measures SB-220 kit, you made far more changes
than simply substituting a resistance wire suppressor for the stock
suppressor.  The changes make a significant difference in anode
circuit resonances and the suppressors cannot be compared directly
for effectiveness.

73,

   ... Joe, W4TV




------------------------------

Message: 8
Date: Sun, 27 Aug 2006 15:15:16 -0400
From: "Tom W8JI" <w8ji@w8ji.com>
Subject: Re: [Amps] Parasitics & Filament Sag
To: "Harold  Mandel" <ka1xo@juno.com>, <AMPS@CONTESTING.COM>
Message-ID: <025701c6ca0d$287723c0$640fa8c0@radioroom>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
        reply-type=original

> Here is what I understand from the consensus of opinion:
>
> 1. VHF Parasitics may develop sufficient amperage
>    such that filaments may physically distort.

That is electrically impossible. There is only so much
emission available, and the force from even many dozens of
amperes is in the order of grams.
It is nearly impossible from filament inrush, it is totally
impossible from oscillations or even excessive RF drive
power.

> 2. Some sort of oscillation can happen as a result
>    of mis-tuning, etc., that may be called "parasitic."

It might be called a parasitic, but it isn't. It also isn't
an oscillation.

If you read this page you will see step by step what causes
a mistuning or load fault arc:

http://www.w8ji.com/demonstation.htm


> 3. The Q of the Lsup device may or may not dampen
>     oscillations or events that may cause filament sag.\

Moot point since it is impossible for an oscillation to
damage the filament, unless it is a mechanical oscillation
like bouncing the tube off a wall.

> 4.  Some 8877 amps have used Lsup devices, some
>     have not.

True. Many do. Many do not.

> 5.  Some commercial manufacturers use Lsup
>     material(s) that are higher resistance than
>     silver strapping with no attempt at an added
>     series inductance.

What is an Lsup?

73 Tom




------------------------------

Message: 9
Date: Sun, 27 Aug 2006 15:08:39 -0500
From: Scott Manthe <n9aa@arrl.net>
Subject: Re: [Amps] Parasitics & Filament Sag
To: Amps@contesting.com
Message-ID: <44F1FBC7.4040806@arrl.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

My guess would be "Lsup" = inductive (parasitic) suppressor.

73,
Scott, N9AA

Tom W8JI wrote:
> What is an Lsup?
>
> 73 Tom
>
>


------------------------------

Message: 10
Date: Sun, 27 Aug 2006 15:34:30 -0600
From: "John T. M. Lyles" <jtml@lanl.gov>
Subject: [Amps] filament forces                          TSPA
To: amps@contesting.com
Message-ID: <p06230904c117bfd62785@[128.165.34.51]>
Content-Type: text/plain; charset="iso-8859-1" ; format="flowed"

Rich
What is the estimated current and the subsequent
force generated to do this pushing of filaments?
73
John
K5PRO

>.... the filament does not sag, rather it is pushed sideways toward the
grid--
>presumably by EMF from the large flow of grid current during the?
>parasitic.  The amount of this current is anybody's guess, but it's
>enough to do damage


------------------------------

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