03-10-2015, 08:26 AM
Quote:Repairing these sets was at times a dangerous occupation. Capacitors contained PCB's; cabinets had asbestos insulation; the solder contained lead; wire insulation was often poor -- and on top of this, the internal operating voltages often exceeded 350 volts!
Obviously written by an imbecile with his/her head up their behind. (And I am most definitely not referring to Bob here! I am referring to whoever wrote this garbage for the Museum of American Heritage website.)
Capacitors in 1930s radios did not contain PCBs.
Cabinets did not have asbestos insulation. Some (chiefly AC/DC sets in the USA) did have a sheet of asbestos under the chassis or in areas where a large amount of heat was generated, yes. But to say they had "asbestos insulation" is an incorrect generalization. Cabinets were made mostly of wood, some metal, some Bakelite, Plaskon or Beetle. They had no insulation inside. Dummy.
Yes, the solder contains lead. DUH! Lead free solder is simply not as good for electronic work, not to mention the little whiskers that are known to grow in lead free solder and wreak havoc with contemporary surface mount electronic devices. That would not have been much of a factor in ye olden days when point to point wiring was used. Lead is not evil. Don't eat the stuff and you'll be fine.
Wire insulation was not poor; it was adequate at the time. Regarding the radios with rubber-covered wire, the rubber didn't start out hard and brittle. Rubber gets that way over time. Radio manufacturers did not intend for their products to still be in service 75+ years on.
Yes, operating voltages could exceed 350 volts in high power audio amplifiers. The radio servicemen of the day were well aware of the high voltages involved; they weren't a bunch of babies who needed someone to hold their hand constantly. They knew the risks, and used something that is fast disappearing from the world today - common sense.
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Ron Ramirez
Ferdinand IN