I vote for the pair of Svetlana GI-7b or GI7BT(same tube) triodes as
replacement tubes for the SB-230.
Tore if you will look at this page on my web site,
You will see a conversion a customer of mine did on a Dentron amp that
ran 4 572b tubes. He used a pair of the Svetlana GI7B triodes, and is
getting about 1200 to 1300 watts out with about 50 to 70 watts of drive.
I dont know the SB-230, so i dont know how much room you would have in
the amp, but a pair of the gi7b tubes would be a little larger than a
pair of the 3cx800a7 tubes. They would also be about $425.00 per tube
cheaper than the 3cx800a7 tubes!
I am not trying to sell you the tubes, my friend Anton at DXHAM.COM can
put you in a pair of those very cheaply. I do have the sockets for those
tubes however which are nearly impossible to find....Just telling you in
case you need them.
Be sure to visit my web sites.
Tom's Tubes. Russian Tubes our speciality..We now carry the Bliss Match
Master line of antenna tuners and antenna switches. Legal Limit PLUS.
Ham Radio Homepage.
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