So What Have I Got Here Boys?

[Captainclock]

Originally Posted by init4fun

Please stop stating things as fact , when in reality you are wrong . The Grundig radio I pictured in my earlier post does indeed have a voltage selector switch , and no power transformer , and IS able to operate from AC or DC power ! It uses a very large , tapped ceramic resistor which the voltage selector switch chooses the appropriate tap from depending on which voltage it selected .

Just so you know , I'm NOT looking to argue here , but I just can't let inaccuracies such as you have printed remain unchallenged . You say you have been at this for 15 or so years , and you seem to think you've seen all there is to see in our hobby . Well , at somewhat over retirement age , and having worked back in the 1960s and 1970s in TV / radio repair , I can with all certainty tell you there is a LOT you haven't seen yet , and that the learning is supposed to be part of the fun of the hobby .

Maybe not but Some people on here are looking to start an arguement, and anyways when I said that stuff I wasn't trying to start an arguement, I have seen quite a few different styles of old tube radios over the years (and thankfully I haven't ever came across a "curtain-burner" type radio) most of the radios I've ever come across were cold chassis type radios with the exception of a small handful of small 1950s and early 1960s vintage "AA5" designed radios that were either Bakelite or wood which are a lot safer to use than the old 1930s vintage "AA5" radios (yes I did know that the "AA5" design for tube radios dated back to the 1930s but I just forgot because I have heard of the "curtain-burner" cords that they used on them before but I just forgot that they were used on hot chassis radios from that time period), and I knew that at least in America we had "universal" as you call them (AC/DC As we called them here in America) but I didn't realize they had such a thing in Europe because I would of figured that such a design would of been considered too unsafe for them over there and that they would of preferred a cold chassis design over a hot chassis design for safety reasons (which like I said is more than likely why they didn't use the AC/DC hot chassis design for very long in their radios). And also usually (at least here in America anyways) if you had a cold chassis designed radio it was usually considered more high end than a hot chassis designed radio so really I would think that this would of applied to European radios as well, which would mean that any of those European radios you have that are "hot chassis" designed are more than likely BOTL models that they were probably cutting corners on.

[dieseljeep]

I always thought, all the German radios had power transformers. The sets sold here, for the north American market, always seemed to have them.
I was surprised to see, so many of their TV's were series string, hot chassis sets, with some of the strangest tube types.
The last of the German tube type Tv's were straight 220 volt design.
When people brought them to the US, they had to be equipped with a step-up transformer. 120/240, auto-transformer type.

[Josef]

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

learning is supposed to be part of the fun of the hobby

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

[init4fun]

Originally Posted by Captainclock

Maybe not but Some people on here are looking to start an arguement, and anyways when I said that stuff I wasn't trying to start an arguement,

I'm glad you didn't see my post as an attack against you personally , because it was not you I was addressing , as much as it was the misinformation that all selectable voltage sets had power transformers/cold chassis . I want you to know that in my younger days I'd develop such notions myself , based on the sets I kept seeing in the shop where I worked , and then wouldn't ya know next week I'd see a set on my bench that a week earlier I'd have bet didn't exist . Weird stuff like a TV that had a transformer for the tube's heaters only , and a hot chassis voltage doubler power supply using selenium rectifiers , or conversely , seeing a set with series heaters and transformer equipped B+ supply cold chassis .

You will see many things like this in the course of your hobby , and to me it's cool to ponder what oddity of engineering would lead to such deviations from the "normal" way most sets were wired .

[Telecolor 3007]

Don't let yourself fooled by something that might have a transformer... some of the transformes might be autotrasnformers - no electric seperation between the electrical network and the electricity inside the device, so if you're not carefoul, bîzzzzt, you may get yourself "fried". Some of the devices do not permit groundig, but other do (the do have separation capacitors).
In Germany thed did used 180 Volts?