[Johnson] Johnson Viking II

[Jim Brannigan]

Interesting substitute.
On the plus side the 866 handles more voltage and current with a lower 
voltage drop.

Negatively, the 866's require 10amps of filament current (per pair) vs. 4 
amps. for the 5R4's.
Additionally, the 866's require time for the filaments to vaporize the 
mercury before HV is applied.
If the 866's have been sitting around, they require a few hours of prep 
before use.

If HV is applied to the 866's before they warm up, they will flash over. 
Not good for the tubes or the Xfmr.

Solid state diodes are the answer.

Jim






>I was wondering if any one has heard anything about the Johnson Viking II 
>being modded to use the 866 mercury Vapor tubes instead of the pair of 5R4 
>it is suppose to use...The reason I am asking is I am acquiring a JV II 
>that has had the 5R4 switched out to a pair of 866's...Any info would 
>greatly be appreciated...Thanks Chris