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
Peter G3RZP
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