[R-390] R-390A front end tubes

[Larry H]

Hi Perry,  Thanks for the offer on Ray Osterwald's article on "a competition grade" 390A.   I have it and have studied it carefully and tried some of his implementations, but am not using any of them due to lack of benefit above what I accomplished with finding low noise tubes.  The only non-standard tube I'm using is a 6BZ6 direct plug-in in the 1st IF.  This only increased my gain by 6% in that stage, (nothing to be concerned about), but did improve my s/n.

Using a 6AK5 or 6HA5 would be a good choice for RF, but they are not direct plug-ins and I really don't need to or see any benefit to improving my .2 uv s/n any farther.

Regards, Larry