[37silverstreak]

This is probably a dumb question, but while replacing the rotted rubber coated wire in my Zenith 12S568 resto, I began to wonder. Was there a specific reason why radio manufacturers used rubber coated wire only in some parts of the set and cloth covered wire in the rest? Just curious and very glad the whole thing isn't wired with it. It's been a pain!
Kevin

[Arran]

I can't really answer that question for certain but if the cloth wire is used on something like a power transformer it may be because the transformer came from an outside supplier. Maybe the lower voltage wiring was rubber covered and the high voltage cloth? Perhaps the stuff that was exposed like grid caps, pilot lamp sockets, and speaker cables got the cloth wire and only the hookup wire inside the chassis was rubber? in any event I replace the rubber crap with vinyl insulated wire, the closest modern equivalent, why pay extra for repro cloth wire when the set didn't use cloth in the first place?
Regards
Arran

P.S Be thankful that most U.S manufacturers didn't start playing with rubber wire until 1939, I have a Rogers Ten-60 currently on the bench that used that crap and it's from 1936. It also used hand wired circuit boards to mount many of the resistors and paper capacitors to, which was connected to the rest of the set with rotting rubber wire, among other delights.

[codefox1]

I believe that bubber coated solid wire would have been easier to strip, wrap and solder, and probably was cheaper to produce, so that's why. Nobody in their right mind then thought about or cared whether it would last 75 years. Even today a box of medical latex (rubber) gloves will turn into slime in about 5 years, and tires rot after 10 years or so.