-----Original Message-----
From: Rob Atkinson
Sent: Thursday, August 02, 2012 5:06 AM
To: Jim Thomson
Cc: amps@contesting.com
Subject: Re: [Amps] The dilemma of Tx tube
Eimac issued engineering newsletter FCJ-59D2 superseding 59B5 which
set forth an exception for the 4-1000A as a high mu triode provided Ep
is at least 3 KV. It listed typical operating conditions.
73
Rob
K5UJ
### Forget the typ conditions. Did it list the typ IMD....
for say 3-4-5 kv..... and at various drive levels.
## Did you get a warranty on a new 4-1000..when you ran it
in GG, then fried the 25 w grid in it.
## The engineering newsletter would pertain to hams wanting to
use the 4-1000 in GG...since there was an abundance of pulls at the time.
The BC DX club had over 200 x 4-1000's between it's club members.
No new commercial amp would ever use a 4-1000 in GG.
They would use a 3-1000Z. I couldn't afford a new 3-1000Z at the
time...and a new 4-1000 was even more $$. 4-1000's were dirt
cheap back then.
## the plate load Z on a 4-1000, with 4400 on it under load is sky high.
I used a 150 pf @ 9 kv Johnson air variable on my 80-15m amp. It was
more than ample for 80m cw. Too much min C on the Johnson + sky
high plate load Z, meant no 10M back in 1976.
## On a similar note, a few of us managed to get the pulse rated
version of the tube, called a 4PR-1000. 9 kv on 80+40m was a real
hoot.
Jim VE7RF
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