07-09-2023, 11:12 AM
Ron -
I have had the spreadsheet for some time but forgot that I had it. I am still getting used to using the plethora of information here (most of which is on my hard drive for convenience). If that is the factory data it is certainly more than sufficient for me. Methods for impedance measurement were around before Philco was building radios. I am close enough to being a dead engineer to appreciate that.
I am currently still involved in a major overhaul of my shop for the first time in a number of years. When that is done I will make some time to measure the voice coil impedances of my Philco speakers and see how they compare with the spreadsheet - that is why I asked about measurement frequency.
The Stancor UOTs which I mentioned should do an excellent job of replacing the Philco OT by selecting the taps for 6,000 plate-to-plate ohms and 1.28 voice coil ohms.
I have had the spreadsheet for some time but forgot that I had it. I am still getting used to using the plethora of information here (most of which is on my hard drive for convenience). If that is the factory data it is certainly more than sufficient for me. Methods for impedance measurement were around before Philco was building radios. I am close enough to being a dead engineer to appreciate that.
I am currently still involved in a major overhaul of my shop for the first time in a number of years. When that is done I will make some time to measure the voice coil impedances of my Philco speakers and see how they compare with the spreadsheet - that is why I asked about measurement frequency.
The Stancor UOTs which I mentioned should do an excellent job of replacing the Philco OT by selecting the taps for 6,000 plate-to-plate ohms and 1.28 voice coil ohms.
Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
https://plymouthcolony.net/starcity/radios/
