[georgetownjohn]

Greetings Phorum members,
Hope you can help me identify this type of wire in the photo I have attached.  I am not sure about the replacement type for it since it is the only rubber covered wire that I have seen thus far in the entire radio(37-640).  Thanks and Happy and S         afe Thanksgiving---John

[Chas]

The red wire is rubber covered wire.

The others are cotton braid over rubber often in colors or a tracer, also strand. The wire size is #20. Generally the filament wires are #18 for larger chassis #16.

In time the sulfur in the rubber rots the cotton and becomes brittle bending the wire will cause the insulation to crack and fall off.


Chas

[morzh]

...and modern wire of the appropriate gauges and insulation V-rating (300V minimum, usually shown right on the wire) is what you need.

[GarySP]

Here's one source for your wire of many.
https://www.tubedepot.com/products/20-ga...olt-rating
Take care and BE HEALTHY! Gary

P.S. Can't get the right color you need? I just buy white and code it by drawing a line on the insulation from end to end with an appropriately-colored Sharpie permanent marker.

[Arran]

It's possible that the red wire, actually a grid cap lead, is a very old replacement, I can't remember seeing a pre 1939 Philco where they used the rubber/gutta percha covered wire for grid leads, that was more of and RCA thing. As to what to use as a replacement, well it is low voltage, and low current, but you also want something mechanically sound, so 10 or 20 gauge, stranded, would do
Regards
Arran

[georgetownjohn]

Thanks to all for the feedback. As Arran said, it is probably an older replacement and yes it has a grid cap so I will use cloth covered 20 gauge stranded and I should be fine.--thanks John