[Chas]

Earlier in this thread the Nostalgia Air URL for this radios schematic was posted. Apparently there is an error in the URL. This URL for the Ford F-1540 should work.

http://www.nostalgiaair.org/PagesByModel...014008.pdf

I do note: That the radio can have either positive or negative connection to the source (battery).

Also, the filter electrolytic can part #62 does have a common positive as the earlier image of the OEM can suggests. The negatives are respectively connected to each side of the filter choke that is in the B- of the power transformer. The chokes resistance also serves as the bias source for the output circuits.

As for noise management in the vehicle:

A.H. Ghirardis Radio Troubleshooters Handbook will provide all the data needed to effectively "noise-proof" the "Woodie":

Hard copy pages are: 505 to 548.

This book was available online but has since been withdrawn. There is one site that offers the handbook but one must register...

https://booksclub.online/book/ezV_ibH0px...538/1939//

This copy is still poor resolution.

The file size I have is 290 MB for the entire handbook, too big to email.

I was able to snip away all but the Auto Radio Service but it is still too big to post, even if the PDF is g-Zipped. I can email to you as a PDF, snipped, it is 18mb within my clients limits. My original PDF copy is poor resolution but by making image file size changes when viewed, the "fine print" can be deciphered.

"Renovated Radios" did have a copy that was hand scanned offered on C-D. Seems since ownership changes, the C-D is no longer available.

Chas