03-28-2020, 12:10 PM
Chas is correct, it would be a 120Hz hum being a full wave rectifier. I used the term 60Hz because that's a common term for this kind of problem that most can relate to.
Anyway, I forgot to mention that when I started the repair, I found that the original filter choke, #48, PN 32-7018, was open.
I only had one spare filter choke available, a Stancor C-1709. The specs for the C-1709 are 8.0 Henries @ 85 Ma DC, DC resistance 250 ohms + 15%
This may or may not be the best replacement for the OE Philco part, but I have not been able to find any specs on the original PN 32-7018 choke.
Does anyone have the Philco 32-7018 choke specs? Or can anyone suggest a better alternative choke than the one I used? does anyone have a spare 32-7018 choke?
Again, it was the only one I had and it did get the radio working so I could repair any other issues. But, considering that the choke is a filtering component in the power supply,
my hum issue might be a result of not using the correct replacement choke.
Anyway, I forgot to mention that when I started the repair, I found that the original filter choke, #48, PN 32-7018, was open.
I only had one spare filter choke available, a Stancor C-1709. The specs for the C-1709 are 8.0 Henries @ 85 Ma DC, DC resistance 250 ohms + 15%
This may or may not be the best replacement for the OE Philco part, but I have not been able to find any specs on the original PN 32-7018 choke.
Does anyone have the Philco 32-7018 choke specs? Or can anyone suggest a better alternative choke than the one I used? does anyone have a spare 32-7018 choke?
Again, it was the only one I had and it did get the radio working so I could repair any other issues. But, considering that the choke is a filtering component in the power supply,
my hum issue might be a result of not using the correct replacement choke.
