On Mon, 22 May 2006 01:44:31 GMT, "JC" wrote:


As I recall the MLA-2500 ran 2200 volts.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com


Roger:

Yes that ia about correct for no load. I am running mine off 120 vac, and
the B+ drags down to about 1600 volts at 0.8 amp load. I've seen other

I'm assuming that is in the tune position? 800 mills sounds kinda
high in the tune/CW position.

Also I was able to get well over 1500 watts PEP out of a pair of 8873s
without driving them hard.

conversions that run off 220 vac, and they say about 1700 volts for the same

It should be just a transformer tap change for 220.

load. The voltage doubler capacitors if increased in value, say 330 uf

It sounds like they are tuning in the SSB mode. The voltage stays
right up there in SSB so if tuned up with carrier in that mode the
tuning will not be correct for SSB.

instead of 125 uf would be better. This however would require adding a
soft-start turn on modification to avoid welding the contacts of the power
switch, or blowing the diode stack.
That lack of regulation is why they run a lot more output PEP when
tuned in the tune/CW position instead of the SSB position.

Years ago I sold and worked on a lot of the Dentron Amps.

Good Luck,

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com


Jim
WD5JKO