[Johnson] Valiant Output

[peter markavage]

Before you start replacing things, get a reasonably accurate VOM or
outboard current meter that requires no external shunts, that allows you
to read DC current. Place it in series in the plate voltage line before
the plate inductor. All voltage must be off to do the connection. Observe
extreme caution with the connections, the leads, and the VOM when the
plate voltage is turned on. The voltage here can be lethal, or at the
very least, knock you across the room if you come in contact with it.
Tune up "normally to about 300 ma on the Valiant meter. Check the VOM
meter to see if it also reads "approx." 300 ma. If way off, check and/or
replace shunt resistor or make your own shunt resistor, so that when
installed, the plate meter on the Valiant reads the same value as the
outboard meter. My Valiant, Apache, Viking II, and several other
boatanchors all have homemade shunt resistors for the plate current and
grid current that, resistance wise, are not exactly the same resistance
as the original meter resistors. Obviously, you have to be comfortable
and very cautious working in this area.

Pete, wa2cwa

On Thu, 22 Dec 2005 10:24:17 -0500 Jim Brannigan <jbrannig at optonline.net>
writes:
> The metering resistors tend to drift higher in value.
> These can all be replaced with parts from Mouser or your favorite 
> supply 
> house.
> 
> Jim
> 
> 
> > When I load my Valiant to 450 ma on the meter, I only get 100 
> watts 
> > output. I've read that its possible that the meter is reading 
> higher than 
> > actual plate current.  Is there a way to calibrate the meter?  
> Regards, 
> > John
> > John D. Littlejohn, W9NET