Holy Smokin' Dummy Load!
Things appear to be working now, I had to do some further refining on my
metering shunts. Turns out I had some odd meters, and my grid current
meter was reading 5X the actual.(the meter said 100mA , but is was actually
only 20mA)
At 3350 Vdc B+ under load (only a 50v drop) at 1.2A I max out my 2000 watt
meter. Its a Daiwa, and I've never checked the accuracy. This works out to
about 50% efficiency. My grid current is around 50mA, and drive is 50-55
watts.
I lost track of time and had to sit the Cantenna outside. Luckily I didn't
damage it.
I'll be playing around with the final tank, and maybe increase the B+ to
see what happens with the efficiency. Many comments cite low efficiency
with this voltage.
So what do I have now? An amp that makes legal limit with 40watts drive,
and does not stress a thing in the box. I have about $1000 tied up so far.
The biggest part in the amp is the pole transformer, which accounts for the
excellent B+ regulation.
The biggest trade off was size. This fella will sit a rack cabinet
(including the transformer). In exchange for this I saved money (not if
your time is money), and built a very durable amp.
73 Jay W7CW
1AB Ranch
Gillette, Wyoming
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