On Sat, 20 Mar 1999 16:20:50 -0500 "Walter Fairclough"
<wfairclo@netcom.ca> writes:
>
>Tested everything that I could test with no 'abnormal' indications.
>Got
>desperate. Took the finals out. Shook them to hear anything strange.
>Tube
>elements in on noisy. Replaced both finals with new Eimacs. 0.82
>resistor
>hasn't blown yet.
>
>Can't seem to get more than about 160 ma of resting plate current.
That is a rather solid indication something is still wrong.
All
>the
>bias diodes check OK. (And, here's something rather strange. Shorting
>out
>bias diodes doesn't change the resting plate current).
That also
Don't seem to
>able to
>get quite as much output as with the old tubes and the plate tuning &
>load
>tuning have changed somewhat.
Tubes wont do that
Tuning on 80M is fairly broad compared
>to old
>tubes. The input SWR also appears to have changed. The FT-1000D is
>having a
>harder time to match the input. Hate to think that I will have to
>modify the
>input circuits.
Think a bit Walt. What didnt you check?
I would start with the caps from each grid pin. Particularly if they are
the old red rectangular types. Next, look for a cracked filament choke
rod or zapped bypass caps.
I suspect the answer will be found in that general area.
73 Carl KM1H
>
>But, first things first. So, I'll be trying straighten out the bias
>situation first.
>
>Devil for punishment.
>
>Walter - VE3EN
>
>
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>
>
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