I need to find out the model number codes for the Sonora radios for 1930-1940. Such as RBU, WDU and WKRU

I am doing research on the company for a future article in ARC.

Thank You

Richard Arnold

Try downloading the "Universal Schematic Locator" at
http://techpreservation.dyndns.org/

You can do searches based on several criteria including year and partial model numbers.

Richard