[R-390] R-390 Poor Sensitivity

[Roy Morgan]

> On Jul 17, 2017, at 8:48 PM, Larry H <dinlarh at att.net> wrote:
> 
> Hi Mark,  The RF deck on the 390/urr can be challenging.

Larry,

Thanks much for your experience and advice on the R-390/URR.  (I have at least one plus variants that will get overhauled after a while). It’ been quite some time since I worked on any of these.

> ...verify that the 3 caps on the 2nd var IF will peak correctly ...... If all 6 resonant circuits do not peak correctly, that is the first thing I'd go after.  I usually find a bad connection on these cans pins or a bad mica cap inside or a bad xtal or switch connection.  Use deoxit very sparingly.  All 3 for each set are the same, so you can swap them around to see if the symptom follows.  


I’m not clear on what you mean here - do you mean that there are 6 resonant circuits In the 2nd IF (two in each IF can)?  Are the mica caps you refer to inside the IF cans?

Thanks for any clarification.

Roy