No cramping here, I don't think Bert has any either.
No, i have a better idea, why don't you filter the rest of us out.
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
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>>> <mailto:amps-request@contesting.com?subject=unsubscribe>
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>>>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
>>
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> >
>>
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>>
>
>
>- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
>www.vcnet.com/measures.
>end
>
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