[R-390] R-390 Non-A module interchangeability

[Norm Drechsel]

I have two R-390 Non-A's, one of which I'm in the process of
restoring.  My question concerns the interchangability of modules
in the Non-A.  I'm used to the R-390A, where all makes and
contracts seem compatible - but even though my two radios are both
Motorolas from the same 14214-PH-51-93 contract (s/n 4127 & 4895)
I've discovered major differences in the power supply module
connector.  Among others I've yet to trace is the B+ center-tap that
goes to ground via the 3/8A fuse is on pin 12 in s/n 4127 and pin
15 on 4895.  I have three power supplies, only one of which is
compatible with the radio I'm restoring.

Has anyone documented these differences?  And if so, are other
modules involved besides the power supply?  The last thing I want
is to smoke a module when testing.

I receive these posts in digest form, so there may be a delay in
my response.

Thanks.

73 de Norm - WA3KEY
norm at wa3key.com