keep 6V Use 12 v battery for devices

[janan5243]

I want to keep my 49 Desoto 6V since everything works fine. Present battery is 6+ yrs old. Might switch to an Optima. Not sure they are worth the additional cost. But I would still like to have a stereo & use mp3 player, GPS & charge phones. Already have a 6V + grd to 12V - grd but it only puts out about 3 Amps. How big a 12V battery would you need to use those devices when driving car or sitting at car show. Does anyone make a generator or an alternator that could charge both size batteries at the same time? I've noticed in the posts that some of you have both batteries. How do you keep 12V charged?

[Merle Coggins]

Get another converter like you have. Run your stereo off of one and wire the second one to a 12v power socket or two, for powering your GPS, phone, etc.

I've got a 6 amp 6-12 volt converter that I have powering my stereo and a pair of outlets for my GPS, iPod, and phone (when needed). I can also power my timing light from it during tune ups.

Merle

[48ply1stcar]

I have concidering a Deep Cycle boat battery mounted in the truck for accessories.

 

Has anybody done this.  I guess when you never drive more than 20 or 30 miles you have low expectations.

[moose]

I put a 12v in the trunk of my 54 back in high school.  Used a cut up extension cord.  It would run the stereo for a long time, I remember charging the 12v on the plug every couple of weeks.  

[Smokeybear]

I have concidering a Deep Cycle boat battery mounted in the truck for accessories.

 

Has anybody done this.  I guess when you never drive more than 20 or 30 miles you have low expectations.

 I bought an AGM deepcycle scooter battery. It is rated to run 35 hours on the scooter. I only run my radio and my LED tail lights off of it and I only charge it twice a month. Works great. Takes up very little space about the size of a motorcycle battery and I have a charger cord hardwired to it so that when I charge it I don't have to get to it behind the truck panel. It was only $60 shipped too. 

[greg g]

I run my gps off my jumper pack. I have also run a radio and speakers from it through a splitter for the power.  I can carry the jump pac in at night for a charge when needed. I do not ever recall running the pac down to nothing while using it.  They are inexpensive enough you could have several and run more than one power outlet, and get fancy running some wiring from the trunk to outlets under the dash or in the glove compartment. I have seen them small enough that they would slide under the front seat.  

 

[janan5243]

The small battery idea is something I was considering. I was going to try to put it on the battery tray with the 6V & run a charging cord so I could just plug it in to charge it. However, I guess I could also purchase another converter. I was going to run 12V to the car cig. lighter & have a multiple jack adapter handy if it was needed. Merle, where did you find a 6 amp converter?

[Tusler 49 New Yorker]

I use an Optima 6v in my 49, it is a fantastic battery and will turn the straight 8 a long time if iit gets flooded.

Optima allso makes a 12 v battery that is half size so the 12 v andn the 6v will fit in your battery tray and you do not have to put it in the trunk or anything.

I am doing the same thing with the 12v and just keeping my radio and whatever isolated from the car and keeping the 6 volt system.

I think most stereos at most take about .5 amp as long as you are not powering a Amplifier.

So you really don't need a big 12v for just the radio.

Edited June 18, 2014 by Tusler 49 New Yorker

[greg g]

Is this the point where we discuss that deal about 6 V positive and 12V negative using the chassis as a common ground at the same time???

[1941Rick]

Would it not be easier to just convert to 12 volt......

[Plymouthy Adams]

Would it not be easier to just convert to 12 volt......

it would but folks want to keep the original six..a hidden battery for the 12 volt accessories is pretty much the best method for them.  Dual dynamos is a headache..going to a single twelve volt dynamo and two 6 volt batteries will give you both power taps but suggest negative ground to prevent accessory power problems, ease of finding parts and accessories.....hard to give just a one bullet answer as each person has their own idea for maintaining their car...what works for one may not sit well for the other...

[Don Coatney]

Is this the point where we discuss that deal about 6 V positive and 12V negative using the chassis as a common ground at the same time???

That is very doable.

[Plymouthy Adams]

Don Coatney, on 18 Jun 2014 - 12:22 PM, said:Don Coatney, on 18 Jun 2014 - 12:22 PM, said:

That is very doable.

while it is very doable..I personally never saw the merit to this approach....most industry (vehicle/tractor) does not do this..however that industry does the single dynamo two battery/two tap approach..again it is very much personal choice which works best...you can get some very crazy voltage reading on a car with both negative and positive dual voltage setup...I know...I helped troubleshoot this very same car earlier pictured here for the last owner when he brought it to me for diagnostics

Edited June 18, 2014 by Plymouthy Adams

[48ply1stcar]

I guess it be easier to keep the 12 volt a isolated and insolated system.

 

Right now I'm too far behind in all my projects and honey-dos.  Maybe the St Paul "Back to the 50's" will get me motivated.

 

http://msrabacktothe50s.com/

[Merle Coggins]

 Merle, where did you find a 6 amp converter?

 

The company is defunct now. It was Meyers Electronics from River Falls, WI

http://community.pressenter.net/~cmeyer/

 

Too bad. It is a nice converter

 

Merle

[DJ194950]

Something like this for small stereo use? 3.5-5 amp. 6 v. pos. to 12 v. neg.Positive Ground 6V to 12V Converter _ Classic Car Radio, Classic Car Stereos, Vintage Car Audio.htm

[Adam H P15 D30]

while it is very doable..I personally never saw the merit to this approach....most industry (vehicle/tractor) does not do this..however that industry does the single dynamo two battery/two tap approach..again it is very much personal choice which works best...you can get some very crazy voltage reading on a car with both negative and positive dual voltage setup...I know...I helped troubleshoot this very same car earlier pictured here for the last owner when he brought it to me for diagnostics

Simplest way I can see is:

Install 12v GENERATOR and reg... Looks identical to the 6v

Change to neg. ground.... No stock radio to fuss about it, avoids problems stated above ^^^^ and most people would not notice anyhow

Run 2 6v batteries in series.... Tap 1 for the 6v stuff and second hidden for 12v adds

Easier than messing around with converters that get hot and with the adds might overwhelm the stock charging system

Easier yet, change it to 12v and quit messing with all this crap

Edit: run the starter on the 12v leg for some quick starts ++++

Edited June 19, 2014 by Adam H P15 D30

[TodFitch]

Something like this for small stereo use? 3.5-5 amp. 6 v. pos. to 12 v. neg.Positive Ground 6V to 12V Converter _ Classic Car Radio, Classic Car Stereos, Vintage Car Audio.htm

 

I think this is a better link for that: http://www.classiccarstereos.com/product/6-to-12-Volt-Converters/PGPI.html

 

And I think that is the way to go. For about the cost of one 12v lead-acid storage battery you are permanently done. No futzing with charging an auxiliary battery with a finite lifetime before it needs replacement.

[Tusler 49 New Yorker]

Would it not be easier to just convert to 12 volt......

Unfortunately I have a hyd electrically shifted M6 semi automatic in my chrysler product. It has a solenoid and a and another part that runs on 6 volts.

The downshifting involves momentary cutout of the coil and ignition system. This just does not work if 12 volts is used. The only way I can convert to 12 v is to change the trans to a newer 727 with a 12 v starter and custom made bellhousing to bolt it all togather. Way more money than I have.

I will just put the 12 v battery in and isolate the system from the car and hook up my Radio and maybe a gps.

Edited June 19, 2014 by Tusler 49 New Yorker

[laynrubber]

For $60 the positive ground 6V to 12V is something I will try, no hassle with another battery and charging it. The rest of the car can stay 6 volt for simplicity and a 12 volt lead acid battery is double the price of this converter.

I used a portable battery pac for a summer, while it worked okay to run the satellite radio I had to use a portable radio on the seat. Got crowded with a radio on the seat and the battery pac on the floor. Was good for about 7 hours of driving.

Edited June 19, 2014 by laynrubber

[Plymouthy Adams]

Unfortunately I have a hyd electrically shifted M6 semi automatic in my chrysler product. It has a solenoid and a and another part that runs on 6 volts.

The downshifting involves momentary cutout of the coil and ignition system. This just does not work if 12 volts is used. The only way I can convert to 12 v is to change the trans to a newer 727 with a 12 v starter and custom made bellhousing to bolt it all togather. Way more money than I have.

I will just put the 12 v battery in and isolate the system from the car and hook up my Radio and maybe a gps.

reference post 11 & 13...

[casper50]

_{http://antiqueautobattery.com/accessories.html}

[janan5243]

Point taken Greg G. Hadn't thought about the ground situation. could still use the stock lighter housing if I isolate it from the dashboard. Moneywise, I guess it would be easier & cheaper to just get another converter since I already have one. Use one for radio & other for accessories. During winter could consider converting to neg. grd. From what I've read on it, it's not a hard thing to do. I think stock radio is only problem. I have three stock radios for car. Am sending one to a shop in Freeport, NY to get it overhauled. Could have him convert it to neg. grd at the same time. Does anyone know of a radio shop near capitol region of NY? I like the 2 6V batteries in series idea. I think 2 Optimas might fit in stock battery tray. I saw a 12v radio with a 6V tap online but it needed a special adapter & I think 1t was 4 to 5 hundred for the setup. With two 6V batteries I could install a setup to jump the starting battery if I needed it I had thought of 2 batteries before but got stuck on figuring how to charge them with the 6V geverator. Never popped into my head to use a 12V generator or alternator. Thanks for all input. Next problem is carb. pouring gas down body to manifold when engine turned off & hot. Have to see exacyly where it's coming from. Will start another thread.

[greg g]

From what I have read, the radios don;t care about polarity.  The humming you hear when you first turn one on is the vibrator, its job is to turn 6 V DC into an AC pattern so its swapping polarity when its on. They may not even be that fussy about input voltage.

 

http://en.wikipedia.org/wiki/Vibrator_(electronic)

[janan5243]

Just checked out site posted by Csasper50. Same site I looked at before. battery I looked at first gives 12V for starting only & can't be used for 12V accessories. Also have to use Battery Tender all the time since it only gets charged at 6V. That is almost $500.00 with shipping. The have another battery the is 12V with a 6V tap for stock accessories. Must change starter & generator. that battery is $280.00 plus shipping. Have to use a charger with at least 10 Amp charge every 10 weeks to keep battery up. Supposed to last 7-10 years. Will add numbers up & make choice. Think the cheapest way is 2 6V in series &12v generator/alternator & convert to neg. grd.