I am not sure exactly what they use. Some are using military surplus,
others use alternators designed for emergency vehicles such as
ambulances.
I would start with those categories. The next time I run into one of
those guys I will ask for some specific details.
A 3CX3000A7 mobile xfmr is rated at 3500VDC @ 1.5A @ 14VAC input. It
is not small, and weighs in at 53 lbs. Price is $379 ...so I have heard..
The 11M boys allow the input volts to vary and are designed with 25KV
insulation. At alternator frequencies it is an easy task to filter the
DC. Many simply use K2AW diode blocks and hope for the best and others
use real diodes of the 3A and 6A variety.
Filament V is derived in many ways. All that I know of use a stock 95A or
similar alternator along with the big one. Some use an inverter and a
standard 51A xfmr. Others use a seperate 12V battery, mounted in the rear
with the amp, with a trickle charger and a resistor to obtain 5V or
whatever voltage they need.
I have personally witnessed mobile installations up to a 3CX20000A7. The
3CX10000A7 is 2nd in popularity behind the 3000 and the 6000 is gaining
in popularity.
Others go the tetrode route and anything from the 4CX3000A and up is fair
game.
I have also seen installations with 3 to 5 big alternators and a racing
type serpentine belt driving them all. This is not for the small engine
category. The GM 350 ci engine with a forged crank will snap. They use
steel racing cranks and/or 454 ci engines.
Popular vehicles are Chevy/GM Surburbans and vans. Others like Dodge.
Ford is not very popular and NO ONE would be caught dead in a RiceBox.
These guys are serious and spend big $$$ .
After all it is just a hobby!
73....Carl KM1H
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