[R-390] Using the 6BZ6 tube

[Perry Sandeen]

Bryon and list.
Chuck Felton (SK) noted in his R390A repair and mod business that the 6DC6 is not a semi-remote cutoff tube (which it was supposed to be) so he used the 6BZ6 instead.  He also recommended that it be used as the 1st RF amp tube in the SP 600.
Chuck was a prolific experimenter as well. He wrote numerous notes on upgrades for the R390A, SP 600 and 75A4 to name a few.  Also he wrote an article for ER radio for simple and effective R390A receivers. 

Hope that answers your good conservative question
73,
Perry KM6FQV