[mikethedruid]

20 ga. wire is rated for up to 11 amps for chassis wiring, although I would never use it for more than 6 amps. The currents in tube circuits in our radios and amplifiers are far below that, usually well below 1 amp, so 20 gauge is actually overkill. More important is the insulation voltage breakdown. I have found that all the modern cloth covered wire I have tested made these days is fine for any voltages they encounter in our sets.