[Amps] Svetlana 572B and FL-2100Z

[Peter Frenning, OZ1PIF]

Alek and Group,

There are at least two diverging opinions on that! In some amps like the
SB200 they are reportedly behaving quite well, wereas they are quite a
handfull in the FL2x00 series of amps, and possibly also in others. My
experience is with the FL2000B and that cost me two sets of tubes! before I
finally gave up and rebuilt the amp using a single QB4/1100 (full story on
my homepage)

Vy 73 de OZ1PIF, Peter

**********  OZ1PIF **************
email: oz1pif(no-spam-filler)@privat.dk
http://home24.inet.tele.dk/oz1pif/
Ph. +45 4619 3239
Snailmail:
Peter Frenning
Ternevej 23
DK-4130 Viby Sj.
Denmark
***********************************
----- Original Message ----- 
From: "Alek Petkovic" <vk6apk at eon.net.au>
To: <amps at contesting.com>
Sent: Saturday, August 28, 2004 2:46 PM
Subject: [Amps] Svetlana 572B and FL-2100Z


> A friend of mine Has recently bought a FL-2100Z and it is fitted with
> Svetlana 572B tubes.
>
> He has had a couple of bangs so far on 20m resulting in the loss of the 22
> Ohm parasitic suppressor resistors.
>
> Also, a previous owner has put 33 Ohm wire wound resistors in the grid
> circuit. The originals were of course non inductive resistors which are
> very hard to source here in Australia.
>
> I am sending him some new 33 Ohm resistors and some nichrome wire to make
> up some new suppressors plus a glitch resistor.
>
> I am also sending him some new Cetron tubes and have advised him to get
rid
> of the Svetlanas and put some extra resistance in the filament line to
> reduce the voltage to a safer value.
>
> Has anybody had any experience with Svetlana 572B tubes? I was under the
> impression that they spelled trouble in hf amplifiers. Is this a fact?
>
> 73, Alek
> vk6APK
>
>
> http://www.qrz.com/vk6apk
> http://profiles.yahoo.com/vk6apk
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>