11-28-2017, 03:02 AM
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
Jim