09-28-2014, 08:10 PM
I finished restoring 2 Philco 16B Tombstones this Summer. A code 121 and a code 125 and did a complete restoration on both of them including rebuilding the bakelite blocks, replacing all the other caps and out of tolerance resistors, stuffing the electrolytics and filter cans as well as doing alignment by the book and now both sets play extremely well with the exception of the shadowmeters on both radios.
Version 1 code 121 meter coil reads 949 ohms and AVC voltage seems to be tracking along with tuning. Also have checked magnet and the "vane" in the assembly returns promptly when flipped with a toothpick. Of course on this version there is no shunt resistor so that isn't the issue either.
Version 125 meter coil measures just over 1100 ohms and shunt resistor is 5,050 ohms. I had read that the resistor was subject to a Philco revision that swapped a 2,500 ohm resistor here so I clipped another 5,000 in parallel and there was no difference in the operation of the meter. I didn't take the code 125 meter assembly apart yet as I'm a little reluctant to take this one apart again since it took me so long to get it working as well as it is now and don't want to take a chance of screwing something up. As I said, both of these are exceptional radios with the exception of the shadow meters, especially the code 125 , getting stations from literally everywhere. I just would like have them truly finished before I put them back in their cabinets. Thanks for any ideas,
Frank
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Version 1 code 121 meter coil reads 949 ohms and AVC voltage seems to be tracking along with tuning. Also have checked magnet and the "vane" in the assembly returns promptly when flipped with a toothpick. Of course on this version there is no shunt resistor so that isn't the issue either.
Version 125 meter coil measures just over 1100 ohms and shunt resistor is 5,050 ohms. I had read that the resistor was subject to a Philco revision that swapped a 2,500 ohm resistor here so I clipped another 5,000 in parallel and there was no difference in the operation of the meter. I didn't take the code 125 meter assembly apart yet as I'm a little reluctant to take this one apart again since it took me so long to get it working as well as it is now and don't want to take a chance of screwing something up. As I said, both of these are exceptional radios with the exception of the shadow meters, especially the code 125 , getting stations from literally everywhere. I just would like have them truly finished before I put them back in their cabinets. Thanks for any ideas,
Frank
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