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Greetings -
What is the purpose of the 2 cardboard-like pieces that are on each end of the field coil in these speakers? Are these asbestos? I've heard that asbestos appears in these speakers in some form and that would be good to know for people working on them. I suspect this material appears in various forms in these radios such as the cardboard and paper insulators. I am not sure about the wiring though or line cord material - this could be just cotton or a woven mix according to supplier catalogs of the period.. Not to scare people but more inform them if this is the case if people have a definitive answer.
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I think the problem is no one knows who Philco's suppliers were during that period of radio manufacture. To start, the best approach is to look through supplier catalogs of the period and try to match against parts observed in radios.
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Welcome to the forum! Not for certain, but I doubt it really.
tractorforum.com *** I reserve the right to be wrong
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I have several of the 70/90 cathedral speakers here and the field coil insulators look to be just plain cardboard to me. I have had a few radios here that had an asbestos heat shield in them, so I am familiar with it. It is usually a white colored material made of a kind of coarse woven cloth-like material. I usually don't worry too much about it, unless it has been damaged in some way.
Ed
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Cardboard or fiberboard...its purpose, I think, was to help insulate the ends of the field from the "pot."
I've never heard of asbestos being used in Philco speakers.
Philco made most of their own parts until 1938. Early on, Jefferson Electric made at least some of their transformers and chokes. After a 1938 strike, Philco began to use more parts from outside sources. Scroll to the bottom of this page for more info:
http://www.philcoradio.com/history/hist3.htm
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Ron Ramirez
Ferdinand IN
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I think that you may be thinking of the fish paper that they used as an insulator, I don't know exactly what it is made from but it isn't asbestos. Whenever I have seen asbestos used in a speaker it's wrapped around the field coil, most often on speakers from the late 30s and into the 1940s but not on something like a Philco 20 speaker. I haven't seen any asbestos insulated wire in an old radio at all, I think that they reserved that sort of thing for appliances like clothes irons and space heaters that draw a lot of current.
Regards
Arran
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I have a philco 20 speaker sitting right next to me. it definitely looks like cardboard to me.