I think, all things considered, that if I were building another
amplifier I would use an 8877 in GG. Easy to tune (unlike my last
tetrode amp), no regulated screen supply needed, no worries about grid
dissipation, and full power at reasonable plate voltage. I suspect that
the total cost would not exceed the cost of a tetrode amp despite the
availability of cheap tetrodes.
3-500Zs require more plate voltage and more drive for 1500w output, and
there is less headroom. On the other hand, they are instant-on.
73,
Vic, 4X6GP/K2VCO
Rehovot, Israel
http://www.qsl.net/k2vco/
On 25 Aug 2015 19:35, Bill Turner wrote:
------------ ORIGINAL MESSAGE ------------(may be snipped)
On Tue, 25 Aug 2015 08:51:40 -0400, you wrote:
I think I've seen, new imported 8877s of reported good quality for the
price of two tested, 3CX800 pulls.
73
Roger (K8RI)
REPLY:
I paid just over $500 for a Pride brand (Chinese) 8877 about four
years ago and it now has hundreds of hours of RTTY contesting on it
and still has full output. It did arc once when it was a few weeks old
and blew the AC line fuses. I replaced the fuses, found no other
damage, and it has been perfect ever since.
I see that Alpha has gone to a single 8877 in their top of the line
9500 amplifier.
IMO, the best tubes, everything considered, for an amateur amplifier
are either a single 8877 or a pair of 3-500Z's. Opinions will vary of
course, but for cost, availability and effectiveness either of those
is hard to beat.
73, Bill W6WRT
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