> 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.
Back in the 30's, tubes had long thin leads. 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.
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.
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 told since then, you
have had a grudge against ETO and all manufacturers.
> 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.
I always wonder how often you do that in "technical" discussions. Why not
leave all the personal stuff about Dick and everyone out, and stick to
honest facts?
73 Tom
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