Hi Osten,
Yes it does, what it is actually about is not the bias per se, but the
cut-off voltage, which has to be higher (more negative!) for the more lively
Svetlana tube. I do not recommend you to use the this tube, I went through
two sets in fairly rapid succession, before I threw the towel in the ring.
My FL2000B is now happily clicking along with a single QB-4/1100, giving
some 600W+ on the lower bands, and about 500W on 10m, something that it
never could manage with the 572Bs, and being absolutely 100% stable and easy
to tune.
IMHO the 572B is totally unsuitable for RF amplification (at least as far as
the Svetlana version is concerned), it is far too temperamental and prone to
take off on its own, instanstantly destroying the tube(s).
If this discourages you from keeping the FL2000B, don't despair, I'm looking
for one more, which I want to convert into a 50MHz amp, using two QB-3/300!
Vy 73 de OZ1PIF, Peter
New DXpedition to Greenland for CQWW! See: http://www.qsl.net/xp1ab
********** OZ1PIF **************
email: oz1pif(no-spam-filler)@get2net.dk
http://hjem.get2net.dk/oz1pif
Shack Ph. +45 4619 3208
Snailmail:
Peter Frenning
Ternevej 23
DK-4130 Viby Sj.
Denmark
***********************************
----- Original Message -----
From: "Osten B Magnusson" <sm5dqc@algonet.se>
To: <amps@contesting.com>
Sent: Tuesday, August 21, 2001 12:41 AM
Subject: [AMPS] 572B and an old FL2000B
>
>
> Hello friends!
>
> I know that some of the Yaesu amplifiers, FL2100B etc
> need another bias supply when using Svetlana 572B's,
> but does this apply to the very old FL2000B also? This
> amplifier is not mentioned in this respect on the Svetlana
> web-site, the USA-site that is.
>
> 73 and thanks in advance de Osten / SM5DQC
>
>
>
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>
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