This past week I did a quick recap and repair of this 7 tube Coronado 1682. Also fixed the loose veneer on the top right rear corner and constructed a back with loop antenna from a scrap piece left over from a TV set. Has 2 bands and 3 tone settings. Nice SW spread from 9 to 12 MHz. Another one saved from the scrap pile. Owner and wife are very happy.
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Hello rod,
What nice little set it reminds me of some those Philco and RCA sets in the little wooden cabinets !
Sincerely Richard
Other than the square antenna the case loks very RCA like a 28X.......and the RCA 28X was AC/DC. Yours looks like a transformer in there.
![[Image: il_794xN.4033056863_3tn2.jpg]](https://i.etsystatic.com/17379717/r/il/e3bc1c/4033056863/il_794xN.4033056863_3tn2.jpg)
Very interesting schematic, definitely not an RCA. I don't think that RCA built OEM Radios for Tire and Department Stores. Coronado (Gamble Skogmo) radios were built by several companies, probably Wells-Gardner, Belmont, Warwick, Detrola, Colonial, Arvin and Kingston Radio Corp.
This radio does have a power transformer with the usual center tapped HV secondary and 2 filament secondaries. One is for the 6X5 rectifier, but the other secondary is for a series 150mA string for a 35L6, 12SQ7, 4 12SK7s and a 12SA7 for a total of 107V. Stranger yet is what these tubes are used for. One 12SK7 is a typical RF Amp, one is a typical IF amp, one is used as the local oscillator and the 4th 12SK7 is wired as a diode as a detector! They must have gotten a deal on 12SK7s!