The GS23B aka 4CX1600U is a wonderful tube for the cost. If you are looking
for a 1500w output pa at 1296MHZ they are not as wonderful because only 1 in
6 or so will make it to that power level.
On the other hand, if you are looking for 1KW output, then maybe 1 in 3 will
make it. If you are looking for 500 to 600W output, then nearly all will
make it.
For best performance, the tube needs to be converted to water cooling. By
performance, I mean when you close the key, power output appears and stays
there
for a reasonable length of time. If you have ever operated a smallish air
cooled pa then you know the drill about power drift.
The above data was collected by testing about 25 GS23B/4CX1600U tubes in a
KD5FZX cavity amplifier.
At the 300 to 400W power level, the GS15B with water cooling works very well
and these tubes are selling for $25 or less. Mats, KD5FZX has built a couple
hundred cavities around this tube and they show up from time to time for
$400 or less. I use one of these cavities to drive a TH347 and it has provided
very stable and reliable service for many years. I drive the GS15B directly
with an FT736R; it just doesn't get any easier than that.
73,
Gerald K5GW
In a message dated 7/26/2008 8:44:01 A.M. Central Daylight Time,
km1h@jeremy.mv.com writes:
Absolutely correct Ian and thanks. Its been a long time since I saw the
various writeups on the U version.
Now that I think of it wasnt 1296 determined to be too much of a stretch for
it?
Im currently using two water cooled 3CX100's on 1296 and Im long overdue for
more power. What are the current Russian choices?
Carl
KM1H
----- Original Message -----
From: "Ian White GM3SEK" <gm3sek@ifwtech.co.uk>
To: <amps@contesting.com>
Sent: Saturday, July 26, 2008 2:19 AM
Subject: Re: [Amps] Tube sources
> Carl wrote:
>
>>>> Svetlana is still made in Russia or one of its ex republics AFIK.
>>>>
>>> Although I don't think they have the full line they were producing. I
>>> sure would like a couple of 4CX-1600Bs
>>That tube was discontinued over a decade ago due to yield problems. I
>>was all set to build a 1296 amp with one as I already had power on 432.
>>
> You'd have been looking for the coaxial-based 4CX1600U, which is still
> available as the GS23B.
>
> Unlike the 8938, which is a coaxial-based 8877, the 4CX1600U is a
> totally different tube from the 1600B, with a different manufacturer and
> development history. The confusing "4CX1600" markings were added by
> Svetlana, purely for the Western market.
>
>
> --
>
> 73 from Ian GM3SEK
> http://www.ifwtech.co.uk/g3sek
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
**************Get fantasy football with free live scoring. Sign up for
FanHouse Fantasy Football today.
(http://www.fanhouse.com/fantasyaffair?ncid=aolspr00050000000020)
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|