[R-390] R390A design improvement

[Perry Sandeen]

List,

Wrote: [snipped] "Why is it that some folks simply cannot leave this wonderful working design alone?  I certainly have YET to see or hear a single individual whom has the mental and design wherewithal that equals, much less*exceeds* the collective knowledge and wisdom of the entire Collins team."

Great question.  OK, below is at least a partial answer. 

Using tubes that did not exist at the time of the original design: The R390A Receiver: A Milestone in HF Communications: Part Three The "Competition-Grade" R390a by Ray W. Osterwald N0DMS Originally Published in E.R Magazine. Also see Cheaper and Simpler Upgrades for the R-390A HF Receiver E.R. 8/04 by Chuck Felton.

Also in the Y2KR3 anthology are several audio improvement circuits including one by Dallas Lankford. 

I’m emailing you an updated copy of both articles.  If any others would like a copy please reply off list.
 
As previously noted, some play golf with Ping Clubs and others get theirs at Sears.  It comes down to a personal choice.

Regards,

Perrier