[MrFixr55]

Using the schematic on Pg 197 of the 1937 Riders, check resistors 1 and 2 and Cap 50. These are in the AVC circuit and a problem here, especially with the cap or with miswiring could cause motorboating.

Is there motorboating when the selector is in the Phono position? If so, check the audio section. Is there motorboating in all bands or just some? Also check the antenna coils (input to grid of RF) for open secondaries.

Is this the 12B or 12W Chassis? Based on the schematic, the 12B is a really neat radio and should really kick it. The 12W should really really kick it!