08-28-2014, 10:56 PM
I located a transformer and have started to unravel the unruly ball of wire left behind by the previous repairs. I am greatly aided in this by Chuck's copies of the service literature which include huge copies of the schematic and the parts map, but I am a bit lost at the capacitor block (part 28 ). I have three questions at this point if anybody can help:
1) The line labeled "D" connects to one of the field coil prongs on the speaker socket and goes from there to the choke (27), but also to lugs 4 and 6 of the capacitor block. Does that mean lugs 4 & 6 of 28 have a jumper across them because they have no connection inside the capacitor block?
2) Line "J" goes from the other field coil prong of the speaker socket to many places. I can trace it to the primary of the input transformer with my DMM through C14, but I have three candidates for this connection at the capacitor block all of which show continuity with the "J" prong of the speaker socket. Answering my own question, I suppose I will need to lift the two capacitor boxes (C7 & C14) slice open the wire wrap, and physically follow the wire. One of the problems here is that the wires come out from the wire wrap a different color than they go in because of previous repairs, so I think taking the wrap off might be the answer here.
3) Once I trace to lug 1 of C28, R18 clearly connects to lugs 1 & 3 in the parts map, but I can't figure out what lug 3 connects to at all. So since "J" goes to lug 1 of C28, the other side of the path from the line coming from "J" must be lug 3. I should be looking for a direct connection between R18, R17 and C14 at lug 3 of C28?
I thought I was doing better at reading schematics, but this one and the ground-up rebuild have me scratching my head.
http://www.nostalgiaair.org/PagesByModel...013838.pdf
1) The line labeled "D" connects to one of the field coil prongs on the speaker socket and goes from there to the choke (27), but also to lugs 4 and 6 of the capacitor block. Does that mean lugs 4 & 6 of 28 have a jumper across them because they have no connection inside the capacitor block?
2) Line "J" goes from the other field coil prong of the speaker socket to many places. I can trace it to the primary of the input transformer with my DMM through C14, but I have three candidates for this connection at the capacitor block all of which show continuity with the "J" prong of the speaker socket. Answering my own question, I suppose I will need to lift the two capacitor boxes (C7 & C14) slice open the wire wrap, and physically follow the wire. One of the problems here is that the wires come out from the wire wrap a different color than they go in because of previous repairs, so I think taking the wrap off might be the answer here.
3) Once I trace to lug 1 of C28, R18 clearly connects to lugs 1 & 3 in the parts map, but I can't figure out what lug 3 connects to at all. So since "J" goes to lug 1 of C28, the other side of the path from the line coming from "J" must be lug 3. I should be looking for a direct connection between R18, R17 and C14 at lug 3 of C28?
I thought I was doing better at reading schematics, but this one and the ground-up rebuild have me scratching my head.
http://www.nostalgiaair.org/PagesByModel...013838.pdf
Charlie in San Antonio
