For those who would like to build a very cheap and simple linear amplifier,
capable of running around 400 - 700W on 160m, take a look at G3YXM's
Throbbatron PA at http://picks.force9.co.uk/shack.htm
Dave Pick G3YXM has built several versions of a linear amplifier using
IXFH58N20 switching MOSFETs (which cost a modest 13 pounds sterling each).
Four of the MOSFETs will give 700W out on 160/80 and 400W on 40m.
G3YXM gives a full circuit and constructional details of a 400W version,
with coil/filter data for 160m, 80 and 40m.
Those of an inventive technical and DXpeditioning bent could probably
convert and string together three or so computer-type switch mode power
supplies, and coupled with the Throbbatron would have a very lightweight
240V low band linear amplifer, capable of packing a good punch. By the way,
don't ask me how to do this - I'm OK on aerials, but that's about as far as
my technical skills go these days...
Also on G3YXM's home page is a very simple magnetic loop design for 160m
(using coax or hardline), which would make a good antenna for confined
spaces, or for those needing a quiet Rx antenna
Check it out!
Vy 73,
Steve, VK6VZ
--
FAQ on WWW: http://www.contesting.com/topband.html
Submissions: topband@contesting.com
Administrative requests: topband-REQUEST@contesting.com
Problems: owner-topband@contesting.com
|