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GPS in a Pos ground Healey?

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AUSMHLY

AUSMHLY

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OK, I admit it. I have GPS in my other car and I'm hooked!
I want it in my Healey, and I want it now! (Yes, I let my inner child out all the time)

I know I can convert my car to neg. But I kind of want to keep it pos. Make up ye mind man.

Here is a link to a Pos DC to Neg DC product by Astron.
They make two units that may work?
1212 and 1212-18

https://www.astroncorp.com/dcdc.shtml

Would one of them work for me?

Portable GPS requires a cigarette adapter. Get one from Radio Shack and wire that out of the Astron.

Too good to be true?
Roger
 
AUSMHLY,
You planning on getting lost?
Randy /ubbthreads/images/graemlins/lol.gif
 
People used to wire -grnd radios into +grnd cars all the time; the radio cases were metal, so they just had to be isolated from the chassis of the car (think wood). Nowadays, with nearly everything being made of (non-conductive) plastic, I'd think it would be pretty easy to do. Just wire a hidden (under the dash) cigarette lighter recepticle reverse ploarity and you'll be set (center of pin to chassis and case__isloated from chassis__to the fuse block).
 
Randy,

Go negative. It is really an easy conversion. Plenty of threads on this subject.
 
Since driving a Healey is always an adventure, and getting lost is just part of it. You'll see more of the country and get to spend more time driving. Where is the problem? Thats why guys don't ask directions.
 
[ QUOTE ]
AUSMHLY,
You planning on getting lost?
Randy /ubbthreads/images/graemlins/lol.gif

[/ QUOTE ]

Presently the only place I'm not lost is under the hood of your car. Smarty pants. Otherwise, yes, I plan on getting lost a lot. I do plan on driving this car everywhere. Like I said, once you have nav, there no going back to maps.
 
[ QUOTE ]
Randy,

Go negative. It is really an easy conversion. Plenty of threads on this subject.

[/ QUOTE ]

Randy's car is already neg.
I'd like to keep my car pos if possible.
 
[ QUOTE ]
Just wire a hidden (under the dash) cigarette lighter recepticle reverse ploarity and you'll be set (center of pin to chassis and case__isloated from chassis__to the fuse block).

[/ QUOTE ]
I like that idea. A cigarette adapter hidden under the dash. The GPS unit gets suction cupped to the windshield. Simply plugs in under the dash. Perfect.

Really that simple?

Isolate the bracket that holds the cig adaptor with rubber or similar fashion so that it does not ground.

The GPS's center pin which is positive, would be connected to center pin of the cigarette lighter, which now becomes a positive ground.

The GPS's outside two pins which are negative, would be making contact with the inside of the cigarette adaptor which is now positive, going to the fuse block. Connected to a fuse?

Is that correct?

I'm not sure I understand. Seems the Negative for the GPS will see positive, being attached to a fuse ?
 
Nope will not work if as you defined. Quit playing games that can damage the electrical sytem of the car. Either get the Inverter and use it or convert the car to Negative Ground.---Keoke- /ubbthreads/images/graemlins/hammer.gif
 
[ QUOTE ]
[ QUOTE ]
Just wire a hidden (under the dash) cigarette lighter recepticle reverse ploarity and you'll be set (center of pin to chassis and case__isloated from chassis__to the fuse block).

[/ QUOTE ]
I like that idea. A cigarette adapter hidden under the dash. The GPS unit gets suction cupped to the windshield. Simply plugs in under the dash. Perfect.

Really that simple?

Isolate the bracket that holds the cig adaptor with rubber or similar fashion so that it does not ground.

The GPS's center pin which is positive, would be connected to center pin of the cigarette lighter, which now becomes a positive ground.

The GPS's outside two pins which are negative, would be making contact with the inside of the cigarette adaptor which is now positive, going to the fuse block. Connected to a fuse?

Is that correct?

I'm not sure I understand. Seems the Negative for the GPS will see positive, being attached to a fuse ?

[/ QUOTE ]
See (crude) sketch...
 

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Thank you for the sketch. Seems simple enough.
Radio shack sells a kit for a cigarette lighter. I has a plastic bracket, just like the one in your attachment. That will isolate the unit.

I would like to put an inline fuse before splicing into the fuse box.

What size fuse is being used at the fuse box?
Where should I attach at the fuse box?
What size fuse should I put inline?

Have you done this to your car, or know of a car this was done to?
Or is this a, this should work exersize?

Thank you Randy.
 
Hey Roger,
If you want to play with the GPS while the ignition is off, plug your new wire in with the brown wire on your fuse block (always hot). The white wires are switched on with the ignition. Check your GPS owners manual for fuse recommendations, but I think 5 amps would be more than enough.
 
As soon as you began to decide to add all these electronics you will soon realize your generator will not keep up. You are going to run out of things to do to the car and you will want driving lights, a stereo, a GPS. Then you will say hey list "how do I add an alternator?". The response will be, first convert to negative ground. Then add an alternator. Humm....................
 
TH, I have looked into the hand held and car units. Some car units have built in batteries. Seems the most you will get is 4-8 hrs. And those hour are for stand by, when you read the small print. Stand by? I would have to bring a house charger with me, for the cig lighter charger will be useless. Units, dead. I need to find an AC outlet to charge it up. How long does it need to charge up. Too much drama.

Bighly, I hear ya. No driving lights or stereo for me. Stereo? Who hears it when the car is being driven? Just keep it simple for me, GPS.

You did bring up a question I did not think of. Will the GPS pull to much electricy. Two concerns. Driving at night, headlights not as bright? Or battery not charging enough, with or without using headlights. Anyone?

Thanks guys, Roger
 
Roger,
With my 64 BJ8, still pos ground, and equipped with an AM-FM, CD player that I use frequently, the battery seems to have no problem holding its charge. I purchased the car in May, 2003 and the battery in the car was about two years old then. I just replaced it this summer with an Optima. The old battery was/is still good. I just wanted an Optima. Anyway, my original generator seems to be working fine for my needs. That said I do not drive the car a great deal at night when the headlights are required. I believe the current draw from the GPS system would be minimal and would not need a fuse larger than 5 amp.
Whether or not it is desireable to change to neg ground and go with an alternator would depend IMO on how much night driving you intend to do and what additional electrical loads you might add, i.e. fog lights, additional brake lights, CD player with a high powered amp, etc.
 
Another option for the GPS or any other electrical device that has an insulated outer case that you may want to use in either a positive or negative ground car is to build a rectifier circut out of four diodes into the power cable of the device. This would allow it to be used in any car no matter what the polarity of the ground. If I remember right, early radar detectors use to have a rectifier circut in line with the power input to prevent damage and allow it to be used in any car. You may also want to double check the tech specs of the GPS just in case it has similar protection built in. If you opt for the plastic cigarette lighter socket, never plug in any of those flexable metal neck lights. If the neck ever touches ground, out comes the lucas smoke.
Here is a link about bridge rectifiers;
https://en.wikipedia.org/wiki/Diode_bridge
 
Come on guys, if it is in a plastic insulated case and attaches to glass just direct wire it to the battery. Use a fuse etc of course. Hide your wires and all that stuff and use quick disconnects and so forth.
 
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