[Johnson] Viking II question(s)

[Telegrapher@worldnet.att.net]

I've got a very nice Viking II transmitter that has served me well for a
number of years.  However, about a year and a half ago it blew a fuse
while in the middle of a transmission.  I just let it set cause i had
higher priorities.  Finally put it on the work table the other day to
see what was doing such a thing.  Found one of the two HV rectifiers
(5R4) blown.  Replaced it and now things are peachy again, except
for......

Oh yeah, also replaced the finals with a better pair of 6293's.  I
noticed before the fuse blowing incident that my plate current would
drift upwards slowly and its still doing that.  But a bigger problem is
that i've never had upward modulation indications on the Ip readings. 
I've done all sorts of gyrations with loading with Course and fine
coupling controls.  Doesn't seem to matter what Ip i load to, still
downward modulation.  

Now an added symptom and i think this is a general observation from what
i've heard over the years is that the metering shunts/resistors in
Johnson rigs are not very accurate.  Nope, i've not measured any of them
so can't verify that rumor.  One of the things that is constant tho is
that when i load up the transmitter, i can never see th reccommended 6ma
Ig.  If you watch the output on a wattmeter, i can see 110W out on
phone, but only with a trace of grid current.  Increasing the drive
causes the output power to drop off.  Still the first problem tho of
downward modulation.  Measured the grid current right at the metering
resistor in the transmitter with VOM and get the same indication as i do
on the transmitter multimeter.  No 6 ma required to get full output
power.  

See there!  multi-problems.  Any thoughts?  It appears that some of the
mods described by NE9G a couple years back for the audio stages has been
done.

CW mode i see 140W out at the 300ma reccommended Ip. 

I'm running the rig thru a variac set for 117Vac.

Suggestions?

Larry