Electric challenge: 12V stereo in our 6V +gnd system?

[Uncle-Pekka]

Are there any electricians at the forum?

I spotted an 12V->6V inverter on a Ford A-model shop. It was, however, quite dear, $100.

http://www.mikes-afordable.com/miva/merchant.mvc?Screen=PROD&Product_Code=A10000CHD&Category_Code=

Then I ran a search at eBay, what did I found:

http://www.ebay.com/itm/Classic-car-6V-to-12V-voltage-converter-power-power-/350436684000

Now the questions I am worried are:

- would this work in +gnd system?

- does it output enough currency to power a CD-stereo set? (likely not, only 15W...?)

But it should be enough for a gadget, that transmits music from a mp3 player to car radio...

I thought one could hook this in the cigarette lighter plug thus it would provide 12V power for cell phone charger and small radio devices at least. Would be "nice feature" to 40's ride.

I asked the supplier the above questions and now waiting for reply.

Stay tuned...

[TodFitch]

Says "common ground" but does not say if it converts from positive ground to negative ground. If it doesn't then you'd have to worry about mounting it in such a way as to isolate it which might not be possible depending on what you are planning on running with it or how you are planning on installing it. For example, you mention using it to power a lighter plug. That may not be possible.

Also calls for a heat sink it you want to run it near its max. Electrically isolating a metal heat sink could add to the challenges.

15watts is probably enough if you are using it to charge cell phones, run a GPS or a MP3 player. It is woefully inadequate for a high powered sound system.

[Jerry Roberts]

Another supplier is MAC's auto parts , they sell parts for the old Fords . They come with either positive or negative ground and work fine for a 12 volt car radio .

[Mark D]

Pekka - found this on ebay...

http://www.ebay.com/itm/Power-Inverter-6v-12v-Positive-Ground-/230889674275?pt=Vintage_Car_Truck_Parts_Accessories&hash=item35c218d623&vxp=mtr

A little more affordable.

[Chester Brzostowski]

Pekka - found this on ebay...

http://www.ebay.com/itm/Power-Inverter-6v-12v-Positive-Ground-/230889674275?pt=Vintage_Car_Truck_Parts_Accessories&hash=item35c218d623&vxp=mtr

A little more affordable.

Mark,

I am using the one you mentioned from Mike's AFordable. It converts 6 VDC positive ground to 12 VDC Negative ground. Works great for a standard AM/FM/CD radio and also powers the GPS. I also have 12 VDC to the cigarette lighter.

Chet...

[Uncle-Pekka]

Thanks all for fast responses & suggestions - I have not got reply for my questions from the eBay seller yet.

Mark,

The one you found looks much alike the one for sale by Mike's Afordable.

However, Mike's list the inverter for 7.5A max current, while this one was listed only 2.5Amps. What is a bit suspicious, the photo at Mike's has text "use 3Amp fuse" on top of the gadget...

Chet,

Do you have one inverter for your stereo and another for cigarette lighter output?

[Uncle-Pekka]

Chet,

OffTopic talk: I noticed you're from Virginia. Mike's Afordable is at eastern border of Georgia - Have you been there to buy parts?

As we have subsidiary in Greenville, SC, I once had a chance to drop by at Mike's to get me some parts. I have to say he has very nice country house and beautiful property there. Even the parts warehouse was built to old style and nice. Also Mr. Mike was a nice person to chat with and deal with. I am sorry we had to sell the model A - If I had the ford, I would definitely be frequent customer at Mike's Afordable.

/Pekka

[Merle Coggins]

The one from Mikes states that it is for Positive Ground 6 volt to 12 volt negative ground at 7.5 amps. I'd go with that one for what you want.

I have this one from Meyer Electronics http://community.pressenter.net/~cmeyer/MES612PG6A.html

It is rated for 6 amps and I power a modern car stereo and a couple of additional cigarette lighter/power sockets for my GPS and iPod charger/phone charger. I've also rigged up an extension cord for my timing light so that I can power it off the power socket so that it'll work on 12 volts.

[Furylee2]

Pekka - found this on ebay...

http://www.ebay.com/itm/Power-Inverter-6v-12v-Positive-Ground-/230889674275?pt=Vintage_Car_Truck_Parts_Accessories&hash=item35c218d623&vxp=mtr

A little more affordable.

I put one of these in my 41 Plymouth (+ ground). I use it to power one of those old FM converters (you know, where you set the am station to 1400 and dial in FM stations). I then listen to FM stations on my original 41 radio.

[BobT-47P15]

I have one that looks pretty much like this one......

bought it used from another forum member a couple

years ago......but haven't used it yet. Was going to

run an aftermarket car stereo/c d player with it.

[Uncle-Pekka]

Hi Fellows,

Now I got the answer by the eBay seller and he recommended an enhanced model:

http://www.ebay.com/itm/LM2577-Input-4-10V-Output-DC12V-3A-High-Current-Power-Module-Regulator-/350586474969?pt=LH_DefaultDomain_0&hash=item51a09511d9

To me it seems we have the winner here: Output enough for moderate CD-stereo system yet low price. Whatda you think?

[busycoupe]

I have an inverter similar to the one in the picture posted by Bob T. It changes 6V+ ground to 12V- ground and uses a common ground. The common ground puzzled me and I contacted the seller about this when I bought the inverter. He explained that the unit actually steps the 6V up to a negative 18V. The negative 18V has a potential of negative 12V from the cars 6V+ ground.

The unit you showed from ebay makes no mention of reversing the polarity. It may only change 6V-ground to 12V-ground which will not do what you need.

Dave

[JIPJOBXX]

I'm not at all into electronics but have some some simple question?

And if I can make one of these units work for me and my old Dodge. As some of you know when I show oft my old car I usually play World War Two Music from a cassette player. I have used in the past a 12 volt battery to play my cassette player. Now being I'm not all that smart about these converters all I would like to know is how to set one of these for my cassette using my six volt battery. Could someone here please lead me through this process?

Here is what I want to do. Converter my six volt power system to 120 volts to play a cassette boom box (small). Also how long could I play a small cassette player with one of these converters?

Second I was thinking of installing a 12 volt radio with a Sirius Satellite radio system and what would I need to do this?

Any and all information would be greatly appreciated and I'm not an electronic guy so please make it simple. Thanks Jon

[TodFitch]

...The unit you showed from ebay makes no mention of reversing the polarity. It may only change 6V-ground to 12V-ground which will not do what you need.

Dave

That is my question too. Based on the description it seems to use a Texas Instruments LM2577 chip for the "heavy lifting". Found a specification sheet for that at http://www.ti.com/lit/ds/symlink/lm2577.pdf Not a real electronics guru, but looking at the sample circuit schematic it appears that it does not do polarity conversion.

[1950 Special Deluxe]

This unit has been discussed before.

I do not have one so I cannot comment on how well they work, but seems to fit the need.

http://www.rediscoveradio.com/

[TodFitch]

I'm not at all into electronics but have some some simple question?

And if I can make one of these units work for me and my old Dodge. As some of you know when I show oft my old car I usually play World War Two Music from a cassette player. I have used in the past a 12 volt battery to play my cassette player. Now being I'm not all that smart about these converters all I would like to know is how to set one of these for my cassette using my six volt battery. Could someone here please lead me through this process?

Here is what I want to do. Converter my six volt power system to 120 volts to play a cassette boom box (small). Also how long could I play a small cassette player with one of these converters?

Second I was thinking of installing a 12 volt radio with a Sirius Satellite radio system and what would I need to do this?

Any and all information would be greatly appreciated and I'm not an electronic guy so please make it simple. Thanks Jon

I think it depends on your boom box.

We've got an old AM/FM/Cassette player that can be run off 110 volts AC or off of D cell batteries. And when I count the batteries it takes I find that they add up to 6v. So for that particular device all I'd have to do is open it up and attach a couple of wires to the battery area and bring them out and attach to the car's power.

A lot of the new stuff that is designed to work with cell phones and MP3 players seem to use 5v. So a simple voltage regulator taking your car's 6v power down to a regulated 5v could work.

Or, worst case, you need an inverter of the type being discussed in this thread to provide 12v power like a more modern car.

[48mirage]

Take a look at these VOLTAGE inverters. http://www.casmfg.com/Accessories.htm

5th item down. I used one of these in my '49 Dodge + ground when I added a 12 volt - ground radio. Since I've stared running a dual voltage system and no longer require this type of device.

The listing you showed http://www.ebay.com/itm/LM2577-Input-4-10V-Output-DC12V-3A-High-Current-Power-Module-Regulator-/350586474969?pt=LH_DefaultDomain_0&hash=item51a09511d9 is a power regulator and requres the same polarity.

[38plymouth]

There is a quick and easy way to play music in your car if you have a smart phone or ipod. I have not done it myself yet but have seen it done. They sell battery powered speakers that plug into your phone or ipod and they also have wireless ones that don't get plugged in. I listen to pandora radio on my phone all the time by plugging it into a stereo with the 3.5 cable. You wouldn't be able to charge the phone/ipod though so I'm not sure how many hours you would get out of it. I want to try the wireless speaker so I could hide it out of view. I doubt the speakers are really loud but I don't think many of us want it that way.

[Jim Yergin]

Second I was thinking of installing a 12 volt radio with a Sirius Satellite radio system and what would I need to do this?

Any and all information would be greatly appreciated and I'm not an electronic guy so please make it simple. Thanks Jon

Jon,

In my '41, I have installed one of those 6 volt +grnd to 12 volt - grnd inverters. I use it to power my Siriuis Stiletto radio and a small stereo ampilfier in my glove compartment. The radio plays through a dual cone speaker I installed in the regular speaker location. It works well for me and I enjoy being able to play appropriate music from the "40's on 4" Sirius channel.

Jim Yergin

[Uncle-Pekka]

That is my question too. Based on the description it seems to use a Texas Instruments LM2577 chip for the "heavy lifting". Found a specification sheet for that at http://www.ti.com/lit/ds/symlink/lm2577.pdf Not a real electronics guru, but looking at the sample circuit schematic it appears that it does not do polarity conversion.

I do not know electronics at all, but it is a DC system, thus if I isolate the radio and speaker totally from the car and connect the 12V output from this gadget to radio ground & car ground to radio +input, there will be 12V voltage in btw input and gnd and the radio will be in -gnd ????

After all isolation in a low voltage DC system is easy & safe trick.

Edited January 5, 2013 by Uncle-Pekka

[Smokeybear]

I went a little different route, I have a jump starter pack that has a 12v power plug (looks like a cigarette lighter plug) I put it behind the seat and run this...

I plug my ipod into it and get a couple of weeks worth of tunes on a charge. I just take the battery pack in the house and plug it in every once in a while. The plus is I have the battery pack in case some of my buddies need a boost and it has a built in air compressor and light in case I get a flat.