11-27-2017, 05:18 PM
Episode 4:
Underneath, things look reasonable but with work to do:
It was once the multimeter was brought to task that the full extent of the situation became apparent, and the scope of the project expanded beyond all previous expectations. In addition to the anticipated repairs, far more serious issues were apparent:
1) Both primary sections of the speaker output transformer were open.
2) The interstage phase-splitter audio transformer primary was open.
3) The shadow meter was open circuit (instructions for repair were provided in my schematic packet).
4) The volume control pot was bad.
At first, I thought ebay might be the salvation - lots of Philco speakers available. All sorts of transformers. But the right ones? Much harder. I nearly snagged a U2 speaker, but the asking price was too rich, well in excess of $100 plus shipping - and for what exactly? I had waded into very deep waters.
I enquired with a transformer repair service. They responded with a reasonable asking price for the job, but too much to justify at the time. A Hammond O/P transformer with configurable taps was ordered for the speaker. It is still in its box. But what to do about that interstage unit?
Meanwhile,to keep things moving, orders were sent out for cloth covered wire, capacitors and other bits and pieces as I contemplated the problems of the difficult stuff. This all gave rise the question: Just what am I trying to accomplish with this radio?
Episode 5 "The Curious case of the Project within a Project" will follow after this brief word from our sponsors...
Underneath, things look reasonable but with work to do:
It was once the multimeter was brought to task that the full extent of the situation became apparent, and the scope of the project expanded beyond all previous expectations. In addition to the anticipated repairs, far more serious issues were apparent:
1) Both primary sections of the speaker output transformer were open.
2) The interstage phase-splitter audio transformer primary was open.
3) The shadow meter was open circuit (instructions for repair were provided in my schematic packet).
4) The volume control pot was bad.
At first, I thought ebay might be the salvation - lots of Philco speakers available. All sorts of transformers. But the right ones? Much harder. I nearly snagged a U2 speaker, but the asking price was too rich, well in excess of $100 plus shipping - and for what exactly? I had waded into very deep waters.
I enquired with a transformer repair service. They responded with a reasonable asking price for the job, but too much to justify at the time. A Hammond O/P transformer with configurable taps was ordered for the speaker. It is still in its box. But what to do about that interstage unit?
Meanwhile,to keep things moving, orders were sent out for cloth covered wire, capacitors and other bits and pieces as I contemplated the problems of the difficult stuff. This all gave rise the question: Just what am I trying to accomplish with this radio?
Episode 5 "The Curious case of the Project within a Project" will follow after this brief word from our sponsors...
I don't hold with furniture that talks.
