Alun wrote:
(N2EY) wrote in
:
In article , Mike Coslo
writes:
On top of all this was the development of grounded-grid zero bias
"Class B" (actually, Class AB2) linear amplifiers for amateur SSB use
in the 1950s and '60s. Most designs required "50 to 100 watts" of drive
power - perfect match for the usual 100W rig. A quad of 811As, pair of
572Bs, a single or pair of 3-400Zs or 3-500Zs, or a single 3-1000Z were
(and still are) common designs. Now ee have ceramic-metal indirectly
heated tubes like the 3CX800A7 which require less drive, but the old
habits die hard...
You might be right about needing a 100W rig to drive most linears, but not
about the 6146s. A pair of 6146 tubes will deliver 280W upto 30 MHz and
half that upto 60MHz acoording to the spec.
You're mistaken, Alun. A single 6146B is rated at 61 watts output in
AB1. So a pair would be at the 120w level.
The old Yaesu FTDX-560 was
rated at 280W out with a pair off 6146s (560W input power, hence the model
number).
You're half right. The FT-DX560 was rated at 560w PEP input power but
it used television sweep tubes.
Dave K8MN