Thank you, you guys for your comments. However, I am absolutely sure about
this. It is quite late right now so I can not dig into my amplifier library.
Even so I refer to W1JR:s article in HAM RADIO February 1985 page 38. And if
my memory not fails, I have seen it in one of my EIMAC papers and discussed
the problem with the EIMAC people during my visit in the factory. And I know
of at least 2 guys who had filaments breaking down in their ALPHA amplifers.
Maybe this amplifier has a overrated filament transformer and no current
limiting due low ohmic transformer windings.
73s de Hans SM5KI
----------
>Från: measures <measures@vcnet.com>
>Till: "Hans Goldschmidt" <sm5ki@algonet.se>, "Jack Brabham"
<w4asm@mindspring.com>, "AMPS" <amps@contesting.com>
>Ämne: Re: SV: [AMPS] PA-77 question
>Datum: mån 13 sep 1999 21.08
>
>
>>Hello!
>>Watch out for that filament inrush current. HAS DESTROYED MANY A 8877. You
>>limit it with a resistor in series with the primary of the filament
>>transformer and short it out after some seconds.
>
>? Although Eimac does provide a warning about limiting inrush current to
>some filament-type tubes like the 3-500Z, Eimac gives no warning about
>limiting current to heater-type tubes such as the 8877.
>
>
>- Rich..., 805.386.3734, www.vcnet.com/measures.
>
>
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