Helo,
I have converted my 1951 Merc to 12-volt negative ground and it works fine. I'm now ready to look at the radio. If I install a 12-volt to 6-volt 15-amp reducer regulator in the radio power circuit to the radio, will the original 6-volt (positive ground) tube radio work. I have read info that some Ford/Mercury radios that were originally positive ground would not work with 6-volt negative ground. Any help would be appreciated.
Thanks, Dave

Sorry to say but your 6 volt positive ground radio will not work in a negative ground now. There is no easy way to fix that I know of. Even to try and insulate the radio chassis from the car body is risky. Maybe someone here has some suggestions about this. But don't hook it up the way it is. You will just Smoke It ..

:Helo,
:I have converted my 1951 Merc to 12-volt negative ground and it works fine. I'm now ready to look at the radio. If I install a 12-volt to 6-volt 15-amp reducer regulator in the radio power circuit to the radio, will the original 6-volt (positive ground) tube radio work. I have read info that some Ford/Mercury radios that were originally positive ground would not work with 6-volt negative ground. Any help would be appreciated.

Thanks, Dave

Your original 51 Mercury radio WILL work either negative or positive ground; UNLESS you have installed a solid state vibrator. These are very polarity sensitive and will burn out in an instance if powered wrong. If you are using a solid state vibrator, all you need to do is get one made for negative ground and you are good to go.

If you are using a mechanical vibrator (hums when working), the radio does not care what the polarity is. The voltage reducer will get very hot, be sure to mount it away from anything that can burn.

Another solution is to have someone convert the radio to operate on 12 volts (again, with a mechanical vibrator, polarity does not matter). I have converted literally dozens of 6 volt radios to 12 volt.

Meade

MAG,
Thats what I was thinking too, but thinking of the Mopar 802 I restored, it was a little fuzzy in my RAM (mostly R), and thanks again for your help on that one.

marv

::Helo,
::I have converted my 1951 Merc to 12-volt negative ground and it works fine. I'm now ready to look at the radio. If I install a 12-volt to 6-volt 15-amp reducer regulator in the radio power circuit to the radio, will the original 6-volt (positive ground) tube radio work. I have read info that some Ford/Mercury radios that were originally positive ground would not work with 6-volt negative ground. Any help would be appreciated.
:
:Thanks, Dave
:
:Your original 51 Mercury radio WILL work either negative or positive ground; UNLESS you have installed a solid state vibrator. These are very polarity sensitive and will burn out in an instance if powered wrong. If you are using a solid state vibrator, all you need to do is get one made for negative ground and you are good to go.
:
: If you are using a mechanical vibrator (hums when working), the radio does not care what the polarity is. The voltage reducer will get very hot, be sure to mount it away from anything that can burn.
:
:Another solution is to have someone convert the radio to operate on 12 volts (again, with a mechanical vibrator, polarity does not matter). I have converted literally dozens of 6 volt radios to 12 volt.
:
:Meade
:
:

:MAG,
:Thats what I was thinking too, but thinking of the Mopar 802 I restored, it was a little fuzzy in my RAM (mostly R), and thanks again for your help on that one.
:
:marv
:
:::Helo,
:::I have converted my 1951 Merc to 12-volt negative ground and it works fine. I'm now ready to look at the radio. If I install a 12-volt to 6-volt 15-amp reducer regulator in the radio power circuit to the radio, will the original 6-volt (positive ground) tube radio work. I have read info that some Ford/Mercury radios that were originally positive ground would not work with 6-volt negative ground. Any help would be appreciated.
::
::Thanks, Dave
::
::Your original 51 Mercury radio WILL work either negative or positive ground; UNLESS you have installed a solid state vibrator. These are very polarity sensitive and will burn out in an instance if powered wrong. If you are using a solid state vibrator, all you need to do is get one made for negative ground and you are good to go.
::
:: If you are using a mechanical vibrator (hums when working), the radio does not care what the polarity is. The voltage reducer will get very hot, be sure to mount it away from anything that can burn.
::
::Another solution is to have someone convert the radio to operate on 12 volts (again, with a mechanical vibrator, polarity does not matter). I have converted literally dozens of 6 volt radios to 12 volt.
::
::Meade

Meade:
The rectifier would give you the proper polarity, but I would look for polarized caps in the 6 Volt wiring, they would have to be reversed. I don't think that many radios had them, but some did, as I recall.
Lewis
::

::MAG,
::Thats what I was thinking too, but thinking of the Mopar 802 I restored, it was a little fuzzy in my RAM (mostly R), and thanks again for your help on that one.
::
::marv
::
::::Helo,
::::I have converted my 1951 Merc to 12-volt negative ground and it works fine. I'm now ready to look at the radio. If I install a 12-volt to 6-volt 15-amp reducer regulator in the radio power circuit to the radio, will the original 6-volt (positive ground) tube radio work. I have read info that some Ford/Mercury radios that were originally positive ground would not work with 6-volt negative ground. Any help would be appreciated.
:::
:::Thanks, Dave
:::
:::Your original 51 Mercury radio WILL work either negative or positive ground; UNLESS you have installed a solid state vibrator. These are very polarity sensitive and will burn out in an instance if powered wrong. If you are using a solid state vibrator, all you need to do is get one made for negative ground and you are good to go.
:::
::: If you are using a mechanical vibrator (hums when working), the radio does not care what the polarity is. The voltage reducer will get very hot, be sure to mount it away from anything that can burn.
:::
:::Another solution is to have someone convert the radio to operate on 12 volts (again, with a mechanical vibrator, polarity does not matter). I have converted literally dozens of 6 volt radios to 12 volt.
:::
:::Meade
:
:
:Meade:
:The rectifier would give you the proper polarity, but I would look for polarized caps in the 6 Volt wiring, they would have to be reversed. I don't think that many radios had them, but some did, as I recall.
:Lewis
:::

Lewis,
I would be interested in knowing about any vibrator powered radios that had polarized capacitors (electrolytics) in the 6 or 12 volt wiring. Possibly European auto radios? There are several vibrator powered radios that are polarity sensitive, notably the Mopar Town & Country sets with a search motor. If polarity is reversed on these, the search motor will run backwards and the tuning mechanism will jam. However, the radio proper will still work either way--just don't operate the search function!

Meade

:::MAG,
:::Thats what I was thinking too, but thinking of the Mopar 802 I restored, it was a little fuzzy in my RAM (mostly R), and thanks again for your help on that one.
:::
:::marv
:::
:::::Helo,
:::::I have converted my 1951 Merc to 12-volt negative ground and it works fine. I'm now ready to look at the radio. If I install a 12-volt to 6-volt 15-amp reducer regulator in the radio power circuit to the radio, will the original 6-volt (positive ground) tube radio work. I have read info that some Ford/Mercury radios that were originally positive ground would not work with 6-volt negative ground. Any help would be appreciated.
::::
::::Thanks, Dave
::::
::::Your original 51 Mercury radio WILL work either negative or positive ground; UNLESS you have installed a solid state vibrator. These are very polarity sensitive and will burn out in an instance if powered wrong. If you are using a solid state vibrator, all you need to do is get one made for negative ground and you are good to go.
::::
:::: If you are using a mechanical vibrator (hums when working), the radio does not care what the polarity is. The voltage reducer will get very hot, be sure to mount it away from anything that can burn.
::::
::::Another solution is to have someone convert the radio to operate on 12 volts (again, with a mechanical vibrator, polarity does not matter). I have converted literally dozens of 6 volt radios to 12 volt.
::::
::::Meade
::
::
::Meade:
::The rectifier would give you the proper polarity, but I would look for polarized caps in the 6 Volt wiring, they would have to be reversed. I don't think that many radios had them, but some did, as I recall.
::Lewis
::::
:
:Lewis,
:I would be interested in knowing about any vibrator powered radios that had polarized capacitors (electrolytics) in the 6 or 12 volt wiring. Possibly European auto radios? There are several vibrator powered radios that are polarity sensitive, notably the Mopar Town & Country sets with a search motor. If polarity is reversed on these, the search motor will run backwards and the tuning mechanism will jam. However, the radio proper will still work either way--just don't operate the search function!
:
:Meade

meade:
Then I guess we would have to make a more general statement, such as: "While the rectifier will give you the right polarity for B+, there still may be polarity sensitive components in the 6/12 Volt circuity that would have to be reversed in order to work properly."
Lewis

Hello again,
Thanks for all your info. I found the following info on another site and have purchased a 12 to 6 volt 20 amp regulated converter to hook up to the stock 1951 Mercury 6-volt radio. I'll let you know how it works.
---Posted by LARRY JORDAN[member] on January 10, 2001 at 21:12:30:
It makes no difference to the radio if your battery is pos. or neg. gr. Just get one of those voltage reducers that looks like a round piece of white ceramic with the curly spring and two screws. Put it in your current supply line. One is all you need. I have mine mounted under the hood, on the driver's side fender well, toward the firewall, in that section down low where nothing will get to it. It's been like that for a couple of years and works fine. Larry
Posted by Keith on January 10, 2001 at 21:41:50:
In Reply to: Re: 6 volt Radio/12 volt system posted by LARRY JORDAN[member] on January 10, 2001 at 21:12:30:
Larry are you saying that you have an original 49-51 Ford radio and you reversed the polarity and it still works OK? I understand dropping the voltage.
Posted by LARRY JORDAN [member] on January 13, 2001 at 22:41:29:
Hello Keith; I do have a stock radio. It makes no difference if your radio is pos. gr. or neg. gr. As long as the wire that feeds the radio through the fuse is a live one, carrying 6-8 volts or so that's all you need.
In Reply to: Re: Let me get this straight posted by Sam on January 10, 2001 at 21:57:08:
The vibrator doesn't know about polarity of the system, except for which direction it first starts to vibrate, which is invisible. And, except for the tube heater elements, the rest of the radio depends on what comes out of the vibrator/step-up transformer circuit.
Different radios (6,7 or 8 tubes) draw different amperages, but your basic 1-ohm, 100 watt wirewound resistor will be close enough. Once the resistor is inline, the radio doesn't know the system is 12-volt, positive or negative. Just be sure to mount the dropping resistor somewhere where it won't be accidentally short-circuited, and where its surroundings can stand to feel a little heat (like that of a 40-watt light bulb). If one knew his way around inside the radio, pairs of tube heater elements could be wired in series to split the 12-volts, and a small dropping resistor could be installed in the vibrator/step-up transformer circuit.
Posted by Keith on January 14, 2001 at 10:37:51:
In Reply to: Re: Let me get this straight posted by LARRY JORDAN [member] on January 13, 2001 at 22:41:29:
Larry, I had never even thought about whether you could change the polarity of a 50 Ford radio and it would still work OK, After looking over the schematic I don't see any reason why it wouldn't work. In regard to the starter button and the solenoid. I can see no reason why the button wouldn't be OK but I am not sure about the solenoid as I recall the direction of current flow determines which way the core moves. For somene who has a hard time remembering what happened yesterday, it is a little bit risky to try and remember what I learned almost 50 years ago.
Posted by 286merc on January 14, 2001 at 11:23:35:
In Reply to: 6 volt Radio/12 volt system posted by RUSS (Member, if Tim ever cashes the check) on January 10, 2001 at 11:53:00:
Hi There, you didn't mention the year but here is a general procedure. Replace the 6V tubes and lamps with 12V equivalents. Use a 12A6 for the 6V6 or if you have the deluxe radio, wire the pair of 6V6's in series if you want. The 12A6 is available as WW2 surplus. Replace the vibrator with a 12V version or go solid state. Similar procedure for most radios using octal, loctal or miniature based tubes. You can get most of the parts from Antique Electronics Supply in Tempe, Az. I'm against using a series dropping resistor since the initial surge will put lots of stress on the tube filaments and the transformer windings. A more elegant solution is to construct an external SS regulator that allows ALL original electrical stuff to remain original, just the starter goes to 12V.
Carl (Rebuilding auto radios for 40+ years)