>
> "If I had but one asterisk for my station, ..." :)
>
> Why stop with an asterisk (*) for 2-radio entrants? What about a
> caret (^) for stations on a hilltop? A dollar-sign ($) for stations
> with a 40m beam? An underscore (_) for those living in a valley? An
> equals-sign (=) for stations with power line noise? Square brackets
> ( [] ) for those living on a city lot? Curly braces ( {} ) for those
> living in the country? An exclamation point (!) for those with TVI
> and angry neighbors?
<snip>
>
> 73,
> Bob, N6TV
>
Actually, Bob, you should take yourself seriously. I find station
data to be very educational. Unfortunatly, no contest write-up has
the space to give a complete station run-down. Once I saw the report
for a 40M contest that included antenna basics, and it was
extremely valuable to me at the time because it allowed me to see
in hard numbers the value of 3 versus 4 elements, yagi versus phased
verticles etc. Let's face it, contest results are pretty dry reading
unless you can synthesize some conclusions from the data. The main
problem is the paucity of data.
73, Dave NG0X
>From ni6t@ix.netcom.com (Garry Shapiro) Fri Sep 16 03:41:50 1994
From: ni6t@ix.netcom.com (Garry Shapiro) (Garry Shapiro)
Subject: Russian tubes
Message-ID: <199409160241.TAA04496@ix.ix.netcom.com>
>From ni6t@ix.netcom.com (Garry Shapiro) Fri Sep 16 04:04:13 1994
From: ni6t@ix.netcom.com (Garry Shapiro) (Garry Shapiro)
Subject: Russian tubes
Message-ID: <199409160304.UAA06537@ix.ix.netcom.com>
Sorry about the blank message preceding this one.
I replied privately re the GU74B inquiry, but perhaps the subject
is of more general interest.
The GU74B ceramic tetrode is being marketed outside the CIS
by Svetlana Electron Devices and is now called the 4CX800A.
The "big brother" referred to by Wirzenius is/was the 4CX1600A.
A newer version of the latter with a larger cooler is now
marketed instead, and is called the 4CX1600B.Svetlana also sells
sockets for these tubes.
Svetlana is sort of the Russian GE. Svetlana means "light." They
have been in the electric business forever and in tubes since 1928.
They have a huge factory in St. Petersburg. Until the breakup of
the Soviet Union, the products were all marketed domestically and
to the Soviet military. Svetlana Electron Devices is an outgrowth
of the collapse of the Soviet Union and the resultant search for
external markets.
Svetlana does not presently market direct equivalents of the
popular Eimac triodes, although some familiar triode numbers (e.g.
833A, 811) are in the catalog, as well as such familiar beam-power
tubes as the 813.
The 4CX800A/GU74B populates the new Alpha amplifier. The tube
retails for about $185--not much more than a quality 3-500Z.
Some information on these tubes has already appeared in such places
as Communications Quarterly. I believe the next issue will have an
article by Marv Gonsior, W6FR, on building an amp with the 4CX1600B.
There are some good arguments for using tetrodes in the new designs,
as discussed by George Badger, W6TC, in an interview I did with him
for The DXer, the NCDXC newsletter. George is now President of
Svetlana Electron Devices.
George argues that the pre-WARC amp designs favored GG triodes because
the need for 5 input circuits (80-10m) was offset by the simplicity
of power supplies. Now, we have 8 bands which allow max power. These
tubes run Class AB1: the input circuit is essentially just a 50-ohm
resistor. The tubes do require a screen supply with the ability to
handle negative screen current, but run on relatively low plate voltage
(2400V)
Svetlana is in both Huntsville, AL (205) 880-8020, and Portola Valley, CA
(415) 233-0429.
No, I don't work for them. I do intend to build an amp, and am amassing parts.
|