I have a Kenwood TS-520S that keeps blowing the 6 Amp line fuse in it.
My Bias control is set for 60ma idle current,
HV is right at 800V
SWR under 1.3:1
It tunes up fine and will run a QSO for about 30 Seconds (CW) then
POOF the fuse blows.
Blows the fuse when operating phone also.

One thing I did find is that the running plate current is a little
high, seems to be about 270-280ma when transmitting, but I can't find
a way to get it lower... adjusting the carrier all the way down has no
effect. rig is putting out 100W on 20 meters

any tips greatly appreciated

Tnx & 73