I'm quoting without names a message from what our CB brethren are up to.
"Take for instance...
2X4CX15,000 being driven by 3X8877
Ep was close to 14 kV on the 15,000s....
Power output was capable of over 80,000 watts Bird. Tuning it up, with
a
1 kW slug in the Bird meter for reverse measurements, we couldn't get it
to
wiggle up to 40 kW forward output. At the 44 kW mark (or thereabouts),
we
blew the top of the antenna off, a nice blue corona came, and the
antenna
spit flames! Nice, to say the least. The tubes are run Class C, and
tetrodes are the tube of choice. What with screen volts, you get better
efficiency. Just have to keep those grids biased WAY negative, and you
can
live with the higher plate voltage.
After that, we went to a "fighting stick" (Quarter wave, usually made
from
3/4 inch copper pipe, chrome plated) and we where able to tune the amp
to
75 kW. It still had more to go, but that was where we left it for a
competition. This was the inaugural run of the amp.
You might wonder where the power comes from for one of these beasts (and
this is smallish. The last one that I saw perform (over 4th of July)
was
capable of nearly 125 kW Avg. output)).
Usually it is a big block motor, using alternators made by the
Electrodyne
company. They are designed as Locomotive Braking motors, but run with a
small voltage on the field, they will act as an alternator... They are
dual
stator, single rotor, producing 60 volts at 600 amps each stator, run
full
field. Run 5 to 7 of these.
Engine: Large stroke, large bore with Nitrous is the name of the game.
Typically see 500+ horsepower.
So, you see, the CB community has really started going nuts. I don't
agree
with the power levels run, but that is what the market "demands".
Like I said, if you want a good "big picture" scene, look at
www.bigradios.com/shadow... Come see what us goofy CBers are doing.
I had one blow the high voltage power supply from my video camera.. I
was
about 100 yards away... This was from near field radiation picked up by
the
power lines."
Oh Boy, Phil W2GE
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