[R-390] R389 and R390 faults

[Rob Filby]

Hi.
     I have recently bought an R389 and a pair of R390 rxs. They are all complete and in good condition.
At first appearance it seems as the PSU, Audio stage and IF strip are interchangable. I have a few 
questions which I would to ask the group and perhaps somebody could help me please.

1.Were any parts listings produced for the above rxs, ie detailing the wattage of resistors and the voltage
ratings of other components?

2.Are there any common faults or other troublesome components that fail or give trouble that I need to be
aware of?

3. I have a couple of R390A rxs which have a mechanical counter for the BFO, why was this used over the 
standard knob?

Thanks for your help

Rob.