10-04-2012, 11:22 PM
Here is a link to some Philco model 29 data at one of my favorite radio sites:
http://www.nostalgiaair.org/PagesByModel...013181.pdf
There is even a parts location diagram for under the chassis, though it does not show wiring, as usual with Philco diagrams. It looks like there are two 8 mf caps and one 10mf cap inside part #64 with the negative end connected to the transformer center tap, they appear to be in the same can. One 8mf has it's positive connected to a filter choke and the input side of the field coil. The other 8mf has it's positive end connected to the output side of the field coil and one end of the primary for the output transformer, the screen grid of the #42 output tube, and a 5000 ohm resistor. The 10mf cap has it's negative end connected to the center tap of the power transformer, the same as the two 8mf caps, and it's positive end connected to chassis ground. The 6 mf cap is called part #61 and is connected between the output side of the filter choke and chassis ground.
All of these caps are mounted in two cans on top of the chassis, nothing underneath other then the wiring, and none can be replaced by a 100 mf 25 volt cap, the strange part is that they are on the opposite end from the power transformer and #80 rectifier. The two 22 mf caps could be used to replace the two 8mf units, or one could be used to replace one 8mf unit and the 10 mf unit.
One thing that you will not like about this set is that it appears to use some form of early circuit board, like an early 30s GE or RCA, this will have to be rebuilt with new capacitors and resistors most likely. The good news is that it looks like all of the parts are facing the bottom of the chassis so you may not have to remove it to replace the caps and resistors mounted to it.
Regards
Arran
http://www.nostalgiaair.org/PagesByModel...013181.pdf
There is even a parts location diagram for under the chassis, though it does not show wiring, as usual with Philco diagrams. It looks like there are two 8 mf caps and one 10mf cap inside part #64 with the negative end connected to the transformer center tap, they appear to be in the same can. One 8mf has it's positive connected to a filter choke and the input side of the field coil. The other 8mf has it's positive end connected to the output side of the field coil and one end of the primary for the output transformer, the screen grid of the #42 output tube, and a 5000 ohm resistor. The 10mf cap has it's negative end connected to the center tap of the power transformer, the same as the two 8mf caps, and it's positive end connected to chassis ground. The 6 mf cap is called part #61 and is connected between the output side of the filter choke and chassis ground.
All of these caps are mounted in two cans on top of the chassis, nothing underneath other then the wiring, and none can be replaced by a 100 mf 25 volt cap, the strange part is that they are on the opposite end from the power transformer and #80 rectifier. The two 22 mf caps could be used to replace the two 8mf units, or one could be used to replace one 8mf unit and the 10 mf unit.
One thing that you will not like about this set is that it appears to use some form of early circuit board, like an early 30s GE or RCA, this will have to be rebuilt with new capacitors and resistors most likely. The good news is that it looks like all of the parts are facing the bottom of the chassis so you may not have to remove it to replace the caps and resistors mounted to it.
Regards
Arran
