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38-1 code 121A
#25

O.K. Back to that rectangular "mystery box"... I've replaced almost all capacitors (except micas and the incorrectly listed ones in the replacement parts list, but I know where they are) and I've tracked down all the parts on the schematics, along with locating the components in the chassis, comparing all to the schematic #'s. All is well, EXCEPT for that lousy box. It is not on the schematics, however, on the box itself is the part # 30-4549. It has 3 leads: one goes to the terminal on the choke, another goes to the other terminal at the choke, and the third goes to a lug at a 3 terminal tie point where #60 and #62 resistors are located. Maybe I'm overlooking the obvious (wouldn't be the first time), But I just don't see it on these schematics. Maybe there was an addendum to the schematics, or part of that ancient repair in 1946? I tried looking for that part # but must have been looking in the wrong section. The chassis is virtually done; all caps baked and re-stuffed, also resistors and cans finished. Just need new RF mounts, a couple of caps & resistors that were out of stock when I purchased my components, and a power cord to finish the electrical... Coincidentally, at the choke is where they cut that .25 cap and 3,000 ohm resistor out. I have since installed a new .25 cap and 3,000 ohm resistor there across the two leads of the choke. (Hopefully that is correct, according to the schematics). I just checked the resistance of #60 & #62 to ground (which are tied together at the lug), and it measures 27,500 ohms. Shall I remove this thing once and for all?

Jim


Messages In This Thread
38-1 code 121A - by Electrothaumaturgist - 09-28-2017, 12:37 AM
RE: 38-1 code 121A - by Radioroslyn - 09-28-2017, 02:29 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 09-28-2017, 03:01 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 10-28-2017, 02:39 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 10-28-2017, 02:51 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 10-28-2017, 03:13 PM
RE: 38-1 code 121A - by morzh - 10-28-2017, 04:04 PM
RE: 38-1 code 121A - by Radioroslyn - 10-28-2017, 04:12 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 10-28-2017, 05:16 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-08-2017, 12:33 AM
RE: 38-1 code 121A - by Radioroslyn - 11-08-2017, 11:50 AM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-08-2017, 10:05 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-08-2017, 10:10 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-08-2017, 10:18 PM
RE: 38-1 code 121A - by Radioroslyn - 11-08-2017, 10:25 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-08-2017, 10:35 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-08-2017, 10:38 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-11-2017, 04:33 AM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-18-2017, 02:21 AM
RE: 38-1 code 121A - by Ron Ramirez - 11-18-2017, 08:05 AM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-18-2017, 10:17 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-24-2017, 11:45 PM
RE: 38-1 code 121A - by Radioroslyn - 11-25-2017, 10:42 AM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-25-2017, 03:35 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-28-2017, 02:02 AM
RE: 38-1 code 121A - by Radioroslyn - 11-28-2017, 12:27 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-28-2017, 12:31 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-28-2017, 12:44 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-28-2017, 01:03 PM
RE: 38-1 code 121A - by Radioroslyn - 11-28-2017, 01:47 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-28-2017, 07:33 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 11-29-2017, 10:13 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-03-2017, 06:55 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-04-2017, 04:53 PM
RE: 38-1 code 121A - by Radioroslyn - 12-04-2017, 06:38 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-04-2017, 07:35 PM
RE: 38-1 code 121A - by Radioroslyn - 12-04-2017, 07:52 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-04-2017, 09:13 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-16-2017, 12:20 AM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-16-2017, 05:48 AM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-25-2017, 03:42 PM
RE: 38-1 code 121A - by EdHolland - 12-26-2017, 09:45 PM
RE: 38-1 code 121A - by Electrothaumaturgist - 12-27-2017, 06:16 PM



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