[Johnson] Valiant problems

[skip]

Hello AM fans,

I have had an on going problem with my Viking Valiant

The mica caps from the bandswitch on 80 and 40 meters get hot and die during
a keydown time of 4 mins or longer into a dummy load at abt 250 plate load.

The mica caps were replaced with 5000v transmitter type mica caps.

The resisters from the parasitic chokes were replaced.

I checked the neutralization on 20 meters as per the manual
that was fine

##  it doesn't smoke  or have any problems on 20 meters

Years ago I remember that some radios would have more then 1 place were the
plate current would dip and give problems.

This has one strong dip

Cleaning the grid drive control pot and variable cap helped stabilize the
grid current

Any ideas as the fix.  I know that the high recirculating currents are
causing the problem but I don't know what to check next

thanks  Skip     K3CC