>
> A number of years ago I had the pleasure of corresponding with an elderly
>amateur in California by the name of Joe Funderburg.
>
> Joe was the smartest person I ever had a chance to talk to about amplifier
>theory.
>
> I cannot remember his call letters but know that he and another amateur,
>(whose call letters I cannot remember either) but I believe it may have been
>William Orr,
** By himself, Joe Funderburg, W6IHA, discovered that gas leakage
could be identified by equal current leakage with both polarities, while
gold-sputter leakage was polarity dependant. He observed that, with
loose gold meltballs inside the envelope, there was more leakage with
positive anode potential than with negative. Typical ratios are on the
order of >5 to 1. Apparently, the electrons in the gold atom are
repelled/dislodged from the anode insulator by negative anode potential.
- Congrats, Joe.
>went through all this more than 10 or 15 years ago when they sliced open a
number of > 8877s
I know of no instance where Bill Orr sliced open a kaput tube.
>and found the problem with the 'sputtering'
>that contaminated the cathodes on those early 8877s (and got the amateurs a
>bunch of free replacements from EIMAC).
I know of no case where Eimac replaced a user-autopsied tube. I received
two free replacement 8875s after Eimac autopsied a kaput pair of 8875s I
sent them - which Eimac then autopsied and found gold-sputtering. [see
Eimac Letter on my Web site]
>
> I also believe they wrote an article about it that appeared in QST.
>
** I do not recall seeing such an article in QST. As I recall, the
first QST article to show an autopsy photo of a gold sputtered tube was
"Parasitics Revisited" in September, 1990. Subsequent to this QST
article , Bill Orr wrote a letter to QST stating that said article
contained numerous technical errors. However, Mr. Orr did not mention
any technical error. QST sent me a photocopy of Mr. Orr's letter.
cheers, Dennis.
> I do not have any more details on the subject because we were QSO'ing about
>another area of high power amplifier design at the time and this was an
>'oh-by-the-way' type of conversation we had.
>
> Unfortunately, when Lucent technologies 'force reduction retired' me on
>November 15th after 37 years of service, they only gave me about 3 hours to
>clear out my many years worth of accumulated 'stuff' and I did not have the
>time to retrieve my email archives; so those details were lost forever.
>
> But if Joe or his friend are still around, and someone out there knows them
>and can contact them, they may be of some help in resolving this issue.
>
>Regards,
>
>Dennis O.
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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