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my 4 tube battery set 39-70 has 5 tubes and an AC cord??
#25

Dan, don't worry about the "purists." We each have our techniques for bringing these old radios back to life. Some people go to the trouble of stripping the guts out of the old wax and paper caps, and stuffing them with new poly caps; I don't. I replace the original caps with their poly cap equivalent, and don't try to hide the changes. I feel that unless this is a museum restoration, it is better to leave clear evidence of MY repair work, for the next guy to be able to see what has been done over the years. Also, I suppose it is just habit. When I started repairing these old sets, they were not considered "antiques." A lot of people just considered them "old junk," which made them cheap to buy and learn on for a budding EE like myself. I simply put in the modern equivalent and didn't worry further. As for your set's conversion, if the tubes were carefully chosen, and the job done correctly, there is no real reason why a farm set so converted should not work as well as it originally did. I will be very interested to see how far your set varies from the original schematic, and how the new B power supply is wired.


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RE: my 4 tube battery set 39-70 has 5 tubes and an AC cord?? - by mikethedruid - 11-01-2014, 12:26 PM



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