>>- Perhaps it's not all that stretchy. During Final Test, a well-used
>>pair of tubes are typically plugged in whilst the frisky Eimac beauties
>>remain safely tucked away in their factory-sealed boxes. . Should one
>>expect that tired old tubes have as much gain as new tubes? . . . I
>>have a tube that was mfg. in 1967, which still works, upon which I will
>>confidently wager a large pizza with 4 toppings and salad bar, that it
>>won't oscillate.
>
>Rich,
>
>Fascinating discussion....
>
>What's the difference between the old tubes and new tubes? Why would the
>old ones not oscillate in an amplifier while the new ones would?
As tubes age, gain decreases. Less gain means less ability to oscillate.
>......did Eimac change something in the design of the tubes?
Eimac decreased the Mu from approx. 190 to approx. 130. The oscillation
situation did not seem to change.
>
>I gotta say, I am on your side in this one so far....but then again, what
>do I know! :-)
>
Carl has not yet proffered another explanation of how the filament gets
bent.
>73,
>Jon
>KE9NA
postscript I tried to send this to your e-mail address. Jon, and it was
rejected.
cheers
Rich...
R. L. Measures, 805-386-3734, AG6K
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