[R-390] Zero adjust R-390

[pete williams]

List...
 I don't  suggest I have the  solution, but  consider the way it operates..... gotta 
have the pictorial from the manual to fully  appreciate. However,when you screw in 
the  knob , the  screwed shaft with knob, presses on a small bar that passes thru the 
main shaft which in turn bears on a  washer that the presses on 3  pins of the spring 
loaded clutch mechanism, . This  allows the PTO to be  temporarily disengaged f rom 
the Veeder  Root indicator and then turning the  kHz knob sets the frequency to  zero 
beat or to what ever point you're calibrating.
It is my opinion that the small bar mentioned  above has broken or .fallen  thru thus 
preventing  disengagement..
I've just repaired one here  after fully  dissasembling but needed the manual.-- also 
strong  fingers to  compress the   concave  springs on reassembly.
 For the R-390,  front panel  screw tensions  are irrelevant. ---my repair and 
checking   done after the RF module  out of the  chassis and on the bench
.
FRONT PANEL PREPARATION.. Being a bit fussy, I like to clean up the  engraved 
lettering on the panel after old paint removal  and prior to repainting.
Some original paints  and the  white filler defy chemical  removal and prior to my 
discovering heat, I laboriously scraped out  every letter  with  a suitable   scriber 
(some of us are  crazier than others  down here in OZ). The paint is  hard but 
recently I cut the time  down by soffening the painted  engravings  with a  fine tip 
soldering iron  and followed  behind  with the  scriber.-- one in each hand. Then a 
brush over  with  a  brass  bristle brush gets it  all off.
I'd take  advise from those  who have  got  a  solvent for the recalcitrant finish.


Pete D..Williams
METUNG, 3904
AUSTRALIA
jupete at bigpond.net.au