[R-390] Zero Adjust - not quite

[Jacques Fortin]

Hello Jerry,

I do not believe that you can swap the R-390A mechanism into a R-390, as
they are different.
This is normal that the PTO still change frequency when you move the KHz
tuning with the Zero Adj. fully in: they are linked at all times.
This is the remaining of the gears that stops to move and the counter as
well.
I just checked with my own "non-A".

73, Jacques, VE2JFE in Montreal

-----Message d'origine-----
De : r-390-bounces at mailman.qth.net <r-390-bounces at mailman.qth.net> De la
part de k1jos at att.net
Envoyé : 9 novembre 2024 14:25
À : r-390 at mailman.qth.net
Objet : [R-390] Zero Adjust - not quite

My R-390 electronically now seems to be workings quite well.  The dial
however is off 1.5kc and I cannot screw down the Zero adjust quite enough to
make the VFO adjustment.  Attached is a picture.  I can see the brass gear
move and the steel plate behind it move a fraction of an inch and the dial
mechanism is very tight to finger movement but not enough and the VFO
changes frequency despite the Zero adjust fully screwed CW.  Also, the
spring that I assume should provide some resistance when not screwed down
seems to have lost its tension completely.  

 

I compared to the Zero adjust from a R-390A, also shown in picture.  Can I
swap the R-390A into the R-390?

 

Jerry