[Ron Ramirez]

The original rubber-covered wire used under the chassis of 1939-42 Philcos was at least 22 gauge. One of these days I really should measure a piece of that old wire with a micrometer. A majority of the under-chassis wire is solid, with stranded used chiefly for wiring to the pushbutton assembly and on IF transformers.

The plastic wire sold by Radio Daze in several different colors is 22 gauge, and is perfect for 1939-42 Philcos.

I'm not saying Mike is wrong, because 18 gauge would be better for the filament string, and 20 gauge would be better for the rest. But what Philco originally used was at least 22 gauge.

I used all 22 gauge in that 41-616 I used to own, which Joe (w4rtc) now owns. It has lots of tubes...I don't even remember how many right now without looking...15? Anyway, I experienced no issues with 22 gauge wire in that radio.