Can a 1951 Ford F-1 radio (6v positive ground) be made to work in a sytem with 12v negative ground.
Thanks

Can be done but not easily, at least as far as I know. The tubes in the radio all have 6 volt filaments so they won't last on 12 volts. There are however, 12 volt equivalents for these tubes. You then have the problem of the power supply transformer that was designed for 6 volts to give the proper voltages on the tubes and related circuits. Replacing the power supply transformer is a lot of work assuming you can find a 12 volt replacement. You will also need to replace the vibrator.
The other possiblity would be to use an external voltage dropping power supply, a simple resistor will not work. I am sure there is somebody who has made this work, so I would search around the net.
Good luck.
Joe, BCA 33493

Joe
I am aware of the problems presented by the voltage difference and would rather not alter the radio. Will the polarity be an issue if the voltage to the radio is reduced to 6v?
Willie

The easy way to convert would be to send it to one of the fellows that guts the old radio and puts in a modern replacement, connected to the old controls. That would give you AM/FM and an Aux input to run something else like a CD player or MP3 player.

Polarity will not be an issue IF you are using an original vibrator. IF the radio has a replacement solid state vibrator then you will have a problem

Bill

I agree with Critterpainter on the polarity issue as long as the vibrator is the original mechanical type and not a replacement solid state or transistorized unit.
Joe, BCA 33493

Thanks for the replies all. Can you recommend someone who guts the old radio and puts in a modern replacement, connected to the old controls. I have some non working radios that would be good candidates. The one in the truck was just restored and should go into a 6v vehicle.
Willie

here is a quick simple and probably the cheapest way to achieve this for a non-electronic person with some basic knowlege-(remember-kiss-keep it simple stupid?) Why not buy two rather small 6 volt utility batteries,(they are under 20 bucks at wal-mart aren't they?)hook them in series,find a place to hide them in the truck and hook them to the main 12 volt power from the truck-then draw your 6 volts for the radio from one of them or both if 6 volts parallel is taken but more work.Wait though,I just remembered the positive ground issue with the radio...hmmm,....well if the radio was isolated that would work easily,I donno right off...need more info,but you can see what my thinking is.

Somewhere in one of the posts a fellow gave the name of a supplier of voltage converters. You can go from 6 volts to 12 or the other way with one of these.
Joe, BCA 33493

I talked to Retro Radio Restorations at Hershey a couple of years ago and played with the demo radio he had setup and picked up his card. Saw he was there again this year. No first hand experience.

Mike Frenchek
717-367-1428
http://www.retroradio.biz/ (not much of a website)
service@retroradio.biz
Elizabethtown, PA

But you can see the eternal problem of the radio being positive ground.Without the radio being isolated somehow from it touching the chasssis ground in the truck,there is no way no how that you can make that work.Ya just can't get there from here.hopefully I didn't spent those years in electronic school for nuthin'...
Sometimes the radio may be designed for positive ground but in fact the ground(chassis of the radio)is not connected to either positive or negative.This would be indicated by two separate power wires(heaviest wires)to the unit instead of just one.Maybe this is the case.Tough call without even a picture.