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Thread: Positive Ground to Negative Ground Power Inverter

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    Positive Ground to Negative Ground Power Inverter

    I have decided to install a Retrosound radio in my BJ8. However, the radio requires a 10 AMP minimum power supply. My power inverter changing positive ground to negative ground power only provides 3 AMPs. I searched on the internet but have not been able to find a power inverter converting positive 12V to negative ground 12V power. Do any of you know where I can find one of these inverters?
    Stever

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    Yoda HealeyRick's Avatar
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    Re: Positive Ground to Negative Ground Power Inverter

    Unless you're doing concours, why not just convert to negative ground? Easy enough to do and no one will ever know unless you look at the battery.
    Rick

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    Re: Positive Ground to Negative Ground Power Inverter

    a

    Well I second Ricks comment, additionaly the converter will add additional problems.

    Yes I know Where U can find one but I do not remember where in my shop I put the cotton picken thing

    U guys down there close to the MTN gonna be warm today----


    NEG GND GO for it OK
    1966 Daimler V8 Saloon; Safely Fast, Built to Last & and; Smooth as Glass.
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    Re: Positive Ground to Negative Ground Power Inverter

    I installed a Petronix ignition years ago. I seem to recall the Petronix is for positive ground and if I convert to negative ground I would have to change out the Petronix ignition. Do you know if that is true?
    Stever

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    Re: Positive Ground to Negative Ground Power Inverter

    Yes, you would have to change the Pertronics but that would be simpler (and probably cheaper) than going the inverter route.

    However, as Rick & Keoke said, if you are going concours the inverter may well be the way to go.

    Dave

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    Re: Positive Ground to Negative Ground Power Inverter

    I am definitely not concours oriented. However, for whatever reason I have found the conversion to negative ground to be "scary".
    Stever

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    Re: Positive Ground to Negative Ground Power Inverter

    I would be a lot more nervous with a 10 amp DC voltage inverter which is actually may be a voltage doubler creating 24 volts positive to float above the 12 volts positive chassis ground. This device used to be used in the early CB radio days so as to be able to "ground" the antenna to the radio frame and chassis. It created a 12 volt DC differential between the radio input and the radio frame. Radio Shack sold it under the Archer brand I recall. Converting to negative ground is very easy and works well. You will need to change the Pertronix and convert the electronic tachometer to negative ground operation. Lots of good articles written on this subject.

    Bill Young
    sjahc.com

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    Yoda HealeyRick's Avatar
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    Re: Positive Ground to Negative Ground Power Inverter

    Here's a negative ground conversion article. Note the tachometer wiring change needed for a BJ8: https://www.carolinasahc.com/Tech%20...iveGround.html
    Rick

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    Re: Positive Ground to Negative Ground Power Inverter

    Quote Originally Posted by stever View Post
    I installed a Petronix ignition years ago. I seem to recall the Petronix is for positive ground and if I convert to negative ground I would have to change out the Petronix ignition. Do you know if that is true?
    Yes that is true:

    However, the negative ground version of the pertronix which has been available for some time is again a simpler installation compared to the negative ground item model,
    1966 Daimler V8 Saloon; Safely Fast, Built to Last & and; Smooth as Glass.
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    Re: Positive Ground to Negative Ground Power Inverter

    I just remembered I am in the process of installing a new positive ground electronic fuel pump, too,,,......ugh. What I would really like to do is install an original radio to the car. I never listen to the radio, anyway, just the exhaust! But, a new style radio in the dash just doesn't look right to me. Anyone have a working "original style" positive ground radio?
    Stever

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    Re: Positive Ground to Negative Ground Power Inverter

    Just a note: stever

    An original style radio may include a switch that makes it compatible with either positive or negative ground systems.
    1966 Daimler V8 Saloon; Safely Fast, Built to Last & and; Smooth as Glass.
    1966 BJ8 [ 2 ] Lil Red & Miss bLU
    1985 XJ6 Saloon
    1948 & 70 Lincoln continentals
    1973 Volvo P1800ES

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    Re: Positive Ground to Negative Ground Power Inverter

    You won't be happy with the Retrosound anyway. At least I'm not. Doesn't pick up stations very well.

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