[R-390] A lesson learned and two questions

[jgedde at optonline.net]

Lesson learned…  Don’t accidentally reverse the connectors for the PTO and the Calibration Oscillator (J115 and J116) on a R-390 (not A).  If you do, it’ll kill the PTO tube.  The connectors are side by side and are identical – not keyed.  Not a great design practice FWIW.

 

And now my first question: on a R390 (not A) is it normal for the ZERO SET knob and shaft to be able to completely unscrew out of the radio?

 

Are there “pearls” for the R390?  Where are they?  Is there a way to search the R390 archives?

 

OK, OK that was four questions.  Two for one sale  😊

 

Cheers!

John