01-15-2013, 08:15 PM
I decided to re-visit a request I made under a better thread title that may catch a few more eyes than my first ever post.
I am working on a 38-690 wherein one of the power transformers has a fried primary. This set has two power transformers and the one in question is shown as item #179 on the schematic (it supplies the audio output stage). I need to know the open circuit secondary voltage out at nominal line input so I can have this transformer re-wound. There are three different Philco part numbers listed for that item number depending on the input voltage range & frequency (32-7885 for 115V/60Hz, 32-7886 for 115V/25-40 Hz, and 32-7887 for 115/230V /60Hz) but I imagine that the design secondary voltage would be about the same for any of them at nominal input.
It was suggested that I look at Chuck Schwark's site or contact him. The data is not on his site and I've not heard back from him. Earlier today another member of the radio club here in Iowa told me he's recieved good information promptly from Chuck in the past but that he's had an open request since before Christmas, so I'm guessing that he (Chuck) may be on vacation.
So, if anyone happens to have some more detailed factory data for this set or that part OR (and I know taking this reading would be a bit of a PITA) if you have a set that uses that transformer and wouldn't mind taking a reading right at the secondary with the rectifer removed, I'd really appreciate it. You could get the reading right at the rectifier socket with the tube pulled on pins 3 & 5.
Thanks very much in advance.
I am working on a 38-690 wherein one of the power transformers has a fried primary. This set has two power transformers and the one in question is shown as item #179 on the schematic (it supplies the audio output stage). I need to know the open circuit secondary voltage out at nominal line input so I can have this transformer re-wound. There are three different Philco part numbers listed for that item number depending on the input voltage range & frequency (32-7885 for 115V/60Hz, 32-7886 for 115V/25-40 Hz, and 32-7887 for 115/230V /60Hz) but I imagine that the design secondary voltage would be about the same for any of them at nominal input.
It was suggested that I look at Chuck Schwark's site or contact him. The data is not on his site and I've not heard back from him. Earlier today another member of the radio club here in Iowa told me he's recieved good information promptly from Chuck in the past but that he's had an open request since before Christmas, so I'm guessing that he (Chuck) may be on vacation.
So, if anyone happens to have some more detailed factory data for this set or that part OR (and I know taking this reading would be a bit of a PITA) if you have a set that uses that transformer and wouldn't mind taking a reading right at the secondary with the rectifer removed, I'd really appreciate it. You could get the reading right at the rectifier socket with the tube pulled on pins 3 & 5.
Thanks very much in advance.
Dave Perkins
Old Radios
Old Volvos
and homebrew beer !
