03-14-2008, 04:25 PM
I just noticed that the MAIN filter capacitor (metal box) C64, which is a 4+8uf/200 volt unit, IS ALSO NON-POLARIZED! Part number is 30-2160S.
I rebuilt it using normal polarized capacitors.
Again, my theory is that since this radio uses a synchronous vibrator supply, if the 6 volt source is connected backward, the B+ will ALSO be backward, which would mean the filter caps would be subjected to reverse polarity. I suppose since the power leads were just large alligator clips, it would be easy to connect them to the wrong post on the battery.
Perhaps Philco made the change after customers complained.
I wonder how long a polarized cap could stand full B+ at reversed polarity?
I rebuilt it using normal polarized capacitors.
Again, my theory is that since this radio uses a synchronous vibrator supply, if the 6 volt source is connected backward, the B+ will ALSO be backward, which would mean the filter caps would be subjected to reverse polarity. I suppose since the power leads were just large alligator clips, it would be easy to connect them to the wrong post on the battery.
Perhaps Philco made the change after customers complained.
I wonder how long a polarized cap could stand full B+ at reversed polarity?
