02-28-2014, 10:11 AM
I have just finished rebuilding my 118 using my original chassis and a donor parts chassis. The chassis was really butchered and had a lot of the cloth wires chewed by a rodent. I found a few errors in the schematic from Nostalgia Air, markup attached.
All I have left is to rebuild the shadowmeter. I have two shadowmeters to build one good one and have a few questions. Both are in good shape mechanically and both coils read on my ohmmeter. However one coil reads 1.4K and the other 850 ohms. From the info on the Philco repair bench the coil has 1000 feet of 40AWG which works out to about 1K resistance. I am not sure if one coil has shorted turns or the other has connection corrosion. What is the nominal resistance reading spec?
Also the schematic shows a shunt resistor, item 76, a 2.9K resistor. I cannot find item 76 on the parts location. Was it added later or perhaps it is built in to the shadowmeter. This might explain the impedance difference between meters if one has it built in and the other doesn't. I guess I should open both meters up to see.
Thanks,
Steve D
All I have left is to rebuild the shadowmeter. I have two shadowmeters to build one good one and have a few questions. Both are in good shape mechanically and both coils read on my ohmmeter. However one coil reads 1.4K and the other 850 ohms. From the info on the Philco repair bench the coil has 1000 feet of 40AWG which works out to about 1K resistance. I am not sure if one coil has shorted turns or the other has connection corrosion. What is the nominal resistance reading spec?
Also the schematic shows a shunt resistor, item 76, a 2.9K resistor. I cannot find item 76 on the parts location. Was it added later or perhaps it is built in to the shadowmeter. This might explain the impedance difference between meters if one has it built in and the other doesn't. I guess I should open both meters up to see.
Thanks,
Steve D
