[R-390] R-390 IF Xfmrs

[Pete Williams]

 D'day all... In my list of IF xfmrs for sale for the R-390/URR I believe
they may have come from a R-725 unless production mods were made

Reason being that in checking them, where was no connectivity from pin #7 to
ground  connexion via the internal coils  as the  schematic for the R-390
says it should be via a 470 k R across a capacitor. 

 Looking at my H/B on the R-725  today, I see that this resistor is omitted
on all of the IF's. although the  capacitor is still there .

  Maybe someone has a reason for this  considering the use the rx was put
to--- band width concerns  or  time  constant perhaps .?

The 'response' could be enlightening.

Thanks 

 

Pete VK3IZ