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Majestic (Grigsby Grunow) 50/52
#16

Progress moving along! I have recapped this beast except for 4 electrolytics that are entombed in tar inside a huge armored box that I have circled in the attached photos. Also found what appears to be a mistake at the factory. On the schematic, the plate circuits for the RF amp and 1st detector are tied together as can be seen in red are on the schematic. Upon doing continuity checking and tracing wires, I can’t find continuity between the plate circuits. I fired it up to take voltage readings and both plates should be at 180v per schematic. The RF amp reads correct but the 1st detector is around 255v, clearly too high and proving both circuits aren’t being sourced from the same B+ as they should be. Drove me nuts tracking it down and I’ve come to the conclusion that it was wired wrong at the factory. It all looks original, not altered so I rewired the 1st detector so that it ties in with the same 180v source as the RF amp and it works. Need to gut that big box for the electrolytics yet and do an alignment. I will see how that goes!

Ron    


Attached Files Image(s)
   

Bendix 0626.      RCA 8BX5.   RCA T64
Philco 41-250.    Philco49-500
GE 201.             Philco 39-25
Motorola 61X13. Philco 46-42        Crosley 52TQ
Philco 37-116.    Philco 70
AK 35                Philco 46-350
Philco 620B.       Zenith Transoceanic B-600
Philco 60B.         Majestic 50
Philco 52-944.    AK 84


Messages In This Thread
Majestic (Grigsby Grunow) 50/52 - by 462ron - 10-14-2022, 08:21 AM
462ron - by 462ron - 10-15-2022, 08:15 AM
462ron - by 462ron - 10-17-2022, 06:48 AM
462ron - by 462ron - 10-19-2022, 08:07 AM
462ron - by 462ron - 10-23-2022, 09:02 AM
462ron - by 462ron - 11-18-2022, 08:55 AM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 11-19-2022, 08:31 PM
462ron - by 462ron - 11-20-2022, 08:35 AM
462ron - by 462ron - 12-12-2022, 08:42 AM
RE: Majestic (Grigsby Grunow) 50/52 - by RodB - 12-12-2022, 09:29 AM
462ron - by 462ron - 12-28-2022, 03:11 PM
RE: Majestic (Grigsby Grunow) 50/52 - by Arran - 01-02-2023, 01:52 AM
462ron - by 462ron - 01-02-2023, 08:13 AM
RE: Majestic (Grigsby Grunow) 50/52 - by RodB - 01-02-2023, 09:50 AM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-02-2023, 10:25 PM
462ron - by 462ron - 01-03-2023, 08:52 AM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-04-2023, 09:41 PM
462ron - by 462ron - 01-05-2023, 08:53 AM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-05-2023, 05:01 PM
RE: Majestic (Grigsby Grunow) 50/52 - by Arran - 01-05-2023, 06:48 PM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-06-2023, 09:46 AM
462ron - by 462ron - 01-06-2023, 10:14 AM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-06-2023, 11:30 AM
462ron - by 462ron - 01-06-2023, 03:50 PM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-09-2023, 06:20 PM
462ron - by 462ron - 01-10-2023, 08:02 AM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 01-10-2023, 08:14 AM
462ron - by 462ron - 01-10-2023, 08:27 AM
462ron - by 462ron - 05-29-2023, 11:17 AM
RE: Majestic (Grigsby Grunow) 50/52 - by morzh - 05-29-2023, 12:29 PM
RE: Majestic (Grigsby Grunow) 50/52 - by MrFixr55 - 05-30-2023, 08:03 AM
462ron - by 462ron - 05-30-2023, 09:10 AM
462ron - by 462ron - 06-29-2023, 08:06 AM



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