The PHILCO Phorum

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Hello All
I have looked at the old post, that have to do with wire size and color. I didn't see much about insulation. My question is about voltage rating of the wire. Is 300 volt insulation enough?
Thankks Bob
I use the RadioDaze NON-RATED cloth covered wire for most everything. They sell a 600 v rated wire but it is an ungainly size. Conceivably the insulation could arc through at high voltage where wires cross or are up against a chassis. There's very few places in a radio that have more than 300 volts present. I'm sure the real world effectiveness of this particular is much higher than 300 volts even though it is not officially rated.

On the other hand, I would be skeptical about a plastic insulated wire only rated at 300 volts.
I restore lots of vintage tube-type equip each yr.For folks that use lots of wire, I personally would suggest new 600v rated wire with pvc jacket. Will last a lifetime. Not authentic cloth-type wire, but the 18 ga stranded works well for me personally. I buy a full 250' roll of communications-type cable- wire every few yrs from Interstate Wire & Cable Inc . The communications cable has 12 separate color-coded, individual 18 ga stranded wires all inside a grey pvc jacket. I cut-off about 5' hacks at a time,carefully strip the outside jacket with a exacto-knife, & the yield is 12 individual / 18 ga/ 600v rated wires in separate colors. A 250' spool is about $60 bucks , and shipping is cheap, fast service also. I save lots of still-usable orig cloth wire from old sets, to match if my customers desire it. Seems to me, the prices of new repro clothwire, is not worth it $$, except for the all=original restorations. But then again, I use lots-o-wire here in my shop ea yr, and most wouldnt need that much all in one purchase. One thing for sure, the roll lasts a long,long time & is user friendly too. Very flexible, and solders very easily. Having 250' (each) of 12 different, color-coded wires, all on one spool for around $60, is hard to beat in pricing!!?? Icon_wink
If I understand correctly, 600v 18 gauge wire...
18G is pretty big wire by comparison to was used. I would consider 20 or 22G 600v insulation.
Thank you for your response I really appreciate it! 

Shaun
AWG 20 and 22 are quite enough. AWG22 will take up to 7 Amps for chassis wiring and this covers most radios even with old tubes. I would not use it in Philco 20 or 70 or 90 if used in non-star topology to wire filaments of 24A and 27 tubes as that could be about 10A (can be used as a star).
In Phico radios, pre 1939 ones at least, they used an early version of cloth push-back wire, there is no rubber under the cloth, other then what comes out of the transformers, and is attached to the filter caps. The original wire hook up wire was around 20 gauge, it's thicker then 22, but thinner then 18, I've used door bell or thermostat wire as a substitute, though I think you can buy a repro version of it, another option is Ceylonese covered wire like Brand Z used in their TV sets. For component leads you can go thinner, but I would not recommend it using thinner then 20 gauge for structural rigidity. When it comes to stranded wore I usually end up using 18 gauge for things like speaker cables, it's hard to get stranded wire where I am any thinner then that, the only local source is auto parts stores.
Regards
Arran