[R-390] Power Supply Modification

[Kenneth G. Gordon]

> Could anyone help with suggestions regarding the 
> substitution for both unavailable rectifiers tubes 26Z5 
> for 1N4007 diodes? I think a series 10 W/470 Ohm 
> resistor is needed...
> Thanking you very much,
> Sam Rocha
> PY1 DKW, Brazil

Although the SS mod can be helpful, in addition to the higher 
voltage problem, there can be other problems using them.

For a possible solution to this common problem visit the following 
URL:

http://www.mines.uidaho.edu/~glowbugs/r390_psmod.htm

I have used this mod and it works very well. The tube used for this 
mod is cheap.

Ken Gordon W7EKB