When rewiring a car to 12 volts I know you can put voltage reducers on gauges and things. But can you put some sort of reducer on a 6 volt radio, and it will work properly or do you have to have it converted to 12 volts? Thanks, sled
I would think a voltage reducer on a radio should work fine. Back in the mid-60's, I converted my 49 Olds to 12 volt. My science classes in school taught me, each wet cell in a battery has 2 volts, so I ran a sheet metal screw in the top of the battery exactly in the middle. With my radio wire connected to the screw, my radio worked great.
One like this should work fine. You want to make sure that it is designed for continuous use, not intermittent or low amperage https://www.chevsofthe40s.com/shop/...GE_REDUCER_V_TO_V_FOR_HEATER_RADIO_GAUGES_ETC Or This http://vintageautogarage.com/dropping-resistor.html
No, not an issue. The thing with the radio is the vibrator. Using a resistor will produce a smooth power source and the radio should operate ok. Test the voltage before you turn the radio on and again during operation. Dave.
Yes. I ran voltage drops to a '51 Chevy 6V radio but those resistors got HOT. So, make sure you provide a heat sink or simply consider where you put them. You can see them on my firewall:
Adding a resistor inline with the power lead will surely reduce the voltage, but how much is the real question. As your radio pulls more power with the volume up, the resistor will drop the voltage more and more. You would be better off changing the vibrator to a 12V type and change the tubes to 12V filament types. After about 1958 most of the AM radios went hybrid, without a vibrator and with 12v filaments in the tubes. Early in the 60's the radios went completely solid state.
The resistor won't start doing it's job until there is current flowing thru it, so checking voltage prior to turning on the radio will show 12V, and as soon as the radio is switched on, a voltage drop thru the resistor will occur, and you should see approximately 6 volts. The exact voltage the radio will receive is dependent on the amount of current the radio requires to operate. And you didn't mention it, but are you maintaining the same battery polarity when you switch to 12V? I haven't tried it, but I've read that some tube style radios will operate OK with either polarity. Not sure about that one, but it might be something to follow up on. Good luck!
I used the 7806 12-6v regulator 25-35ufcap set up same as with the gauges, blower motor, inline to the original radio, and 12v switched hot wire to the new radio, that way either one is useable. http://www.youtube.com/watch?feature=player_detailpage&v=1gvQjwMrQ9k
You can put these together yourself for $3-$4, I mounted mine to some heat sinks I salvaged from some junk "boom Boxes". Parts available at your local independent electronics supply or if you have to at Radio Shack.
6V radio will work on 6V from a resistor or other power source. If it is a tube radio it will draw a lot of power - 5 to 10 amps on the bigger sets. Marty's suggestion of a center tap from the battery is excellent, possibly the best and cheapest source of 6V power. A 6V radio can be converted to 12V by changing the vibrator and tubes.
I was thinking about this as well, could be wrong but I don't think the radio will like negative ground. If someone knows for sure I would like to know.
Since I have not converted a 6V tube/vibrator radio to 12V, I may be wrong (and often have been), but wouldn't you have to address the increased voltage being applied to the radio's power transformer due to 12V vs. 6V? And the voltage rating of the power supply's filter capacitors, etc? It might work just fine, but I'm skeptical that the conversion would be that simple. Maybe someone else can jump in here and add their opinion and/or expertise.
You bring up a good point! Let's say you pull 6V square wave from the 6V vibrator, then step up to 300V. That would be 50 times more of step up in the transformer. Now let's say you get 12V square wave from 12V vibrator and feed the same 1:50 transformer. You should get something around 600V. As you brought out, the components, (tubes included) might not be rated for that high voltage. And if the filaments are derived from same transformer, they will also be running at double their rating. What could be done is to feed the vibrator output to a 2:1 stepdown transformer, then off to the power transformer. That way it is not current sensitive as a dropping resistor is.
Thanks for all the input fellas. I brought my radio into work today and have a guy who is an electrical whiz checking it out. I'll post when he lets me know what he comes up with. sled
The vibrator supplies the correct AC high voltage. The tube heaters are 6 or 12 volt. I don't think there is anything polarity sensitive except the vibrator. In any case this is not supposed to be a complete radio repair manual covering the conversion of every radio ever made. I am trying to convey the information that yes, it is possible to change a radio from 6 to 12V. Suggest you find a vintage radio forum or do a web search for specifics. I used to frequent some old radio forums and found the patrons very helpful.
The vibrator is just a set of points and the power transformer is like the ignition coil. So yes you would need to change the power transformer if going to 12v. Need to change vibrator and tubes and don't forget the dial lights. Tube radios with mechanical vibrators will work on positive or negative ground. You can get a solid state vibrator in positive or negative ground.
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