>Rich said;
>
>>// WOID said that the 8877 manufacturing defect was produced for c.
>14-months.
>
>The copy I have of W0ID's email to N2JV suggests the fault appeared with the
>design changes of 8/86, and the second 'fix' saw initial deliveries in 8/88,
>while completion of field upgrade was 5/89. There is a caveat:
>
>>>** NOTE: Because tube date codes approximate
>>> shipping rather than manufacture dates,
>>> they may vary ~1-3 months from the
>>> event dates given above.
>
>So given one's druther's, I'd suggest avoiding late '85 to mid '89. To quote
>W8JI:
>
>>Back around 85, we couldn't get a good 8877 to save our souls. I
>>built a test fixture that cycled tube filaments off and one without
>>any HV, just watching for G-K shorts, and after several hours very
>>few tubes remained good.
>>
>>Since then, like with all tubes, there have been good batches and bad
>>batches. The bulk of the problems were gone by the early 90's.
>
>
>73
>
// Tnx, Peter. There may be yet another manufacturing defect since,
as I recall, Mr. Rauch stated that recent failures in the AL-1500 were
still Eimac's fault.
cheers
- R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.
end
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