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Philco 66, 37-61, and 38-10, Evolution Of A Design
#1

I have restored all three of these radios over the years, and the detailed threads on the work can be found here:
Model 66B
Model 37-61B
Model 38-10
However, a quick look at their schematics tells the tale. From the Model 66, to the Model 37-61, to the Model 38-10, we see the evolution of a 2 band All American 5.

[Image: https://64.media.tumblr.com/5508e135e754...0d8553.jpg]
[Image: https://64.media.tumblr.com/1fbee4fddbf3...660aa0.jpg]
[Image: https://64.media.tumblr.com/32a6c8e58d00...4df859.jpg]
Even their frequency coverage is similar:
Model 66  540 - 1720 KC and 5.7 - 18 MC
Model 37-61  530 - 1720 KC and 5.7 - 18.2 MC
Model 38-10  540- - 1720 KC and 5.7 - 18 MC

Over the years the styling changed from the "beehive" cabinets of the 66B and 37-61B to the "bullet" styling of the 38-10T. The performance improved only slightly, but is surprisingly good for radios without a tuned RF amplifier stage before the mixer oscillator. They cover the entire AM broadcast band, and the old "low police band" which was popular for people to listen to police calls back in the days when it was used, just as police scanners are today. The shortwave band covers all the frequencies most often used for international broadcast. With a decent antenna they pull in the stations surprisingly well.
#2

Hello mike,
very interesting.

Sincerely Richard




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