Hello!
At first I want to point out that nobody should be offended because of anything. Honestly I don't know everything about american sets, otherwise I know a lot about our european sets.
So it is definitely true that the mixed mains voltages caused a real chaos here in Europe. In some districts of Vienna DC mains were present until 1957. So the set I posted before is definitely able to operate with 110 to 240V AC and DC without a switching PSU of course. What I didn't mention was the fact that this circuit has significant disadvantages:
hot chassis, much heat because of the serial resistor in the heater chain at higher voltages like 220 and 240V, poor performance at 110V because of the lowered plate voltage, mains plug has to be pluged in in the right position at DC otherwise the set will not work.
Here you can download the schematic if you are interested:
http://www.4tubes.com/SCHEMATICS/Rad...x_img/374U.jpg
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learning is supposed to be part of the fun of the hobby
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by init4fun
@dieseljeep: Most, but of course not all, of the german and austrian TV sets had serial heaters and hot chassis also the sets from the mid 50s. There are many reasons for this: safe costs and weight for a power transformer. AC and DC compatibility and so on.
My own combo which I itroduced here:
http://www.videokarma.org/showthread.php?t=256949 also has a serial hot chassis and is AC and DC operational. If you really wanted to supply the set with DC a tube DC/AC converter was available as a feature to feed the AC motor of the Dual record player.
Greetings Josef