>No cramping here, I don't think Bert has any either.
>
** Good
>No, i have a better idea, why don't you filter the rest of us out.
>
** I filter spam.
>Fight on.
>
>Dale J.
>
>
>
>>Filter out the Subject with your E-mailer app., and the cramping will go
>>away.
>>
>>>I agree with you Dale. Let's move on to something more interesting.
>>>
>>>Bert A.
>>>
>>>
>>>-----Original Message-----
>>>From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]On
>>>Behalf Of dj2001@mn.rr.com
>>>Sent: Tuesday, March 04, 2003 8:51 AM
>>>To: amps@contesting.com
>>>Subject: Fwd: Re: [Amps] 8877s, ETO and the General Electric Contract
>>>
>>>
>>>
>>>This reminds me of a bloody barroom brawl. It's getting kind of ugly
>>>sorry to say and I'm not learning anything useful about amplifiers.
>>>
>>>Dale J.
>>>
>>>
>>>
>>>
>>>
>>>>Subject: Re: [Amps] 8877s, ETO and the General Electric Contract
To: <amps@contesting.com>
>>>>Date: Tue, 4 Mar 2003 07:47:55 -0800
>>>>From: rlm <2@vc.net>
>>>>To: "Tom Rauch" <w8ji@contesting.com>, " AMPS" <amps@contesting.com>
>>>>X-BeenThere: amps@contesting.com
>>>>X-Mailman-Version: 2.1
>>>>List-Id: <amps.contesting.com>
>>>>List-Unsubscribe: <http://lists.contesting.com/mailman/listinfo/amps>,
>>>> <mailto:amps-request@contesting.com?subject=unsubscribe>
>>>>List-Archive: <http://dayton.akorn.net/pipermail/amps>
>>>>List-Post: <mailto:amps@contesting.com>
>>>>List-Help: <mailto:amps-request@contesting.com?subject=help>
>>>>List-Subscribe: <http://lists.contesting.com/mailman/listinfo/amps>,
>>>> <mailto:amps-request@contesting.com?subject=subscribe>
>>>>Sender: amps-bounces@contesting.com
>>>>X-Virus-Scanned: Symantec AntiVirus Scan Engine
>>>>
>>>>
>>>>
>>>>> I started to have this problem in 10th grade and the problem isn't
>>>going
>>>>> away.
>>>>>
>>>>>The problem is rooted in false claims, poor technical advice, poor circuit
>>>>>behavior descriptions, and general misinformation. Unless the correct
>>>>>information gets out, the problem will continue. We should concentrate
>>>more
>>>>>on technical issues, and less on what we "imagine".
>>>>>
>>>>> ** Interesting, Dave. I apparently assumed wrongly. My take on the
>>>>> issue is that GE knew more about the 8877 failure problem in ETO
>>>>> amplifiers than is assumed by some. GE's awareness of the VHF
>>>parasite
>>>>> problem goes back to 1935, when GE engineer G. W. Fyler wrote about the
>>>>> problem in "Parasites in Transmitters" in the Sept. issue of the IRE
>>>>> Journal. // The first Eimac technical data sheet on the 8877 was
>>>>> published in 1970. Eimac's W. B. Foote told me that the gold-migration
>>>>> problem was discovered by the 8877 development team. Thus, they must
>>>>> have known about the gold-migration phenomenon at least 16-years before
>>>>> Foote told me about it in February of 1986.
>>>>>
>>>>>Neither the Foote letter nor GE said anything of the sort.
>>>>
>>>>I have no idea what GE said to Dick E.
>>>>The Eimac Letter:
>>>>=======================
>>>>"VARIAN ElMAC, 301 Industrial Way
>>>>San Carlos California 94070 1 U.S.A. / Tel. (415) 592-1221 TWX 910
>>>>376-4893
>>>>February 18, 1986
>>>>
>>>>Mr. Richard L. Measures
>>>>6455 La Cumbre Road
>>>>Somis, CA 93066
>>>>
>>>>Subject: 2 pcs returned 8875 S/N G8AD-241 and F8VD-428J, for evaluation.
>>>>Reference: Your letter dated 21 January 1986; EIMAC RPA #SC-2303.
>>>>
>>>>Dear Richard:
>>>>
>>>>Your letter about parasitics is quite interesting, and it appears your
>>>>two tubes have had the same trouble. The emission was poor on test, and
>>>>consequently other test results looked bad. The tube engineer then cut
>>>>them both open for an internal examination.
>> >>Both have been badly overheated internally, the apparent result of an
>>>>oscillation condition. The grid in these tubes is gold plated and if
>>>>overheated the gold vaporizes off, of course, and some of it inevitably
>>>>lands on the oxide cathode, and that poisons emission.
>>>>
>>>>Though your tubes are quite old (mid-1978 vintage) we will replace them
>>>>in the interest of good user relations. We will scrap the two you sent in
>>>>here, as we have to be sure they are out of circulation when we replace.
>> >>Good luck in your continued operation.
>>>>
>>>>Sincerely, WILLIS B. FOOTE, Chief Specifications Engineer, Power Grid
>>>>Division."
>>>>------------------------------
>>>>** I take this letter to say that gold apparently evaporates during an
>>>>oscillation condition.
>>>>>
>>>>>Back in the 30's, tubes had long thin leads.
>>>>
>>>>** Some still do. However, low L leads only move the problem higher
>>>>because the ability to oscillate also moves up.
>>>>
>>>>>Nearly every amplifier was
>>>>>operating at the upper frequency limit of construction, components, and
>>>>>wiring. Becuase the amplifiers were operated near the limits, having very
>>>>>poor tubes, wiring, and components by today's standards there was no
>>>>>effective way to stabilize the PA's.
>>>>>
>>>>** G.W. Fyler (and F. E. Handy) came up with a simple idea that proved to
>>>>be fairly handy -- i.e., "the plate or grid parasitic circuits should be
>>>>damped with resistance". (GWF. Sept.1935)
>>>>
>>>>>It was impossible, in the 30's, to get enough transfer from current in
>>>>>inductance to the dissipative resistance as the frequency of oscillation
>>>is
>>>>>approached because the operating frequency and instability frequency much
>>>>>closer than they are with devices even from the 40's and 50's.
>>>>>
>>>>** Say what ?
>>>>
>>>>>Because of poor layouts and poor components amplifers had to be
>>>gain-reduced
>>>>>even near the operating frequency.
>>>>>Only a fool would think that has some universal meaning in modern systems.
>>>>>It would be like insisting jet engines use gravity-fed fuel systems, which
>>>>>worked so well in the early days of aviation. Vastly different systems
>>>>>almost always require different solutions, when looking for the optimum.
>>>>>
>>>>> The story I got was that GE was concerned with the tube failure rate.
>>>>>
>>>>>The story I heard was you applied for a job at a major amplifier
>>>>>manufacturer, and your application was rejected.
>>>>
>>>>** I was a metrologist who also taught electronics. Amplifier building
>>>>was just a hobby that started when I was 15.
>>>>
>>>>>I was told since then, you
>>>>>have had a grudge against ETO and all manufacturers.
>>>>>
>>>>** I didn't know anyone who got cremated in a Ford Pinto or Crown
>>>>Victoria rear-ender.
>>>>
>>>>> plant. When I mentioned the 150 figure on AMPS a couple of years
>>>later,
>>>>> Dick said I was going insane.
>>>>>
>>>>>I know you say some things here that you attribute to me that I never
>>>said.
>>>>
>>>>** Like the letter I received from a person who claimed to be Tom Rauch
>>>>which threatened to sue me and QST if my Rebuttal to the 9-94 QST was
>>>>ever published in QST? If this person was an impostor, his timing was
>>>>uncanny since his letter arrived about a 10-days after I mailed a copy of
>>>>my Rebuttal to the real Tom Rauch.
>>>>
>>>>>I always wonder how often you do that in "technical" discussions. Why not
>>>>>leave all the personal stuff about Dick
>>>>
>>>>** Dick E. played the Insane Card and I said so.
>>>>
>>>>>and everyone out, and stick to
>>>>>honest facts?
>>>>
>>>>** Like when the smoke began to clear at the end the Grate Parasitics
>>>>Debate, when your faithful groupies were suggesting that I was probably
>>>>boinking the teenage girl who was filling suppressor retro-fit kit orders
>>>>?
>>>>>
>>>>Cheers, Tom
>>>>
>>>>- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
>>>>www.vcnet.com/measures.
>>>>end
>>>>
>>>>_______________________________________________
>>>>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
>> >
>>>
>>>_______________________________________________
>>>Amps mailing list
>>>Amps@contesting.com
>>>http://lists.contesting.com/mailman/listinfo/amps
>>>
>>
>>
>>- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
>>www.vcnet.com/measures.
>>end
>>
>>_______________________________________________
>>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
>
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
end
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