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Re: POS or NEG Ground better?

To: CarlSereda@aol.com, triumphs@autox.team.net
Subject: Re: POS or NEG Ground better?
From: ArthurK101@aol.com
Date: Thu, 15 Jul 1999 16:11:39 EDT
In a message dated 15-Jul-99 15:04:40 Eastern Daylight Time, 
CarlSereda@aol.com writes:

> so ..what's the bottom line? - is one better than the other in some way?
>  Carl
>  
 
Carl, Don't think it matters -- as long as the correct polarity is noted and 
observed.  That means the DC generator field circuit has to be properly 
polarized and the coil connections must be such that the spark comes off the 
center electrode at the spark plugs. (See British Car magazine Jun/Jul '97 
p.44 for an excellent explanation on LBC ignitions.)  Of course, jumping your 
dead battery from another car with the opposite gnd also requires care.  You 
don't hook Gnd to Gnd but must hook pos to pos and neg to neg.

However -- one problem with Pos ground is that it is difficult, if not 
impossible, to buy many modern accessories (like Radios/CD players) which 
will work with pos gnd without being modified.  Since negative ground has 
been standard for so many years the electronics manufacturers make their 
equipment that way.

The first radio I bought in '64 had a switch on the radio for pos or neg 
ground.  But that was a very simple AM band tube radio with maybe one 
transistor.  So it was easy for the manufacturer to make it switchable.

When I tried, in '91, to install my current AM/FM/Cassette radio I had some 
difficulty.  When I called JVC to see if they could give me a "quick fix " 
they wouldn't even discuss it.  Their engineer told me that the radio was for 
negative ground and that they would take no responsibility if I altered it 
for use with pos gnd.  He also said that he was prohibited from telling me 
how to alter some of the circuitry inside the radio.  I bought an inverter 
for the radio circuit and that, in effect, fooled the radio into thinking 
that the car was negative ground.  That inverter burned out last month.  

I'm probably going to convert the TR4 to negative ground this fall.  If I had 
had access to the list in '91 that is probably what I would have done then. 
(Would have saved me $100 for the inverter.)  But I wasn't sure what else 
needed to be done to convert the car to negative ground.  Now I know that the 
conversion is very simple -- the lights and the gauges don't even have to be 
touched.  The conversion eliminates the modern accessory problem.  Dan 
Masters has kindly provided all the necessary info about converting pos to 
neg ground and put it up on the VTR website.  Hope that helps.  Cheers.

Art Kelly

Art Kelly

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