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sethb
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Just wondering -- I have a PASO battery-powered PA system that runs on a 12-volt internal battery. That battery is charged with a gizmo that plugs into AC current and (I assume) converts it to DC. I also have a separate portable rechargeable 12-volt battery (the Xantrex 200) that can output either AC or DC.

I'd like to use the Xantrex to extend the battery life and operating time of the PASO battery, but the Xantrex's AC output is not a "pure" sine wave and could damage the PASO's electronics. So I don't want to plug the Xantrex AC output into the PASO AC gizmo. Plus, it seems to me that there is a much simpler and easier way to do this --- by taking the DC output from the Xantrex and directly using that to power the PASO. But I don't know whether it's possible to make that kind of connection, or how to do it. I do have a DC patch cord that came with the Xantrex unit, but it's a "cigarette lighter" type connection at both ends. The PASO's DC input is a small cylindrical pin-type jack, like you see on many household devices that plug into an AC outlet but run on DC. The PASO DC input says it takes 12-15 volts, 4 amps.

It seems to me that if I could supply the PASO unit with DC power, I could get around the pesky and expensive problem of inverters, sine waves and so on, plus eliminate the power loss from converting to AC and then back to DC. All magicians who are licensed electricians or physics majors are invited to help solve this mystery! Thanks in advance for your help. SETH
"Watch the Professor!!" -- Al Flosso (1895-1976)
"The better you are, the closer they watch" -- Darwin Ortiz, STRONG MAGIC
Bill Nuvo
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I was thinking this was about the band...

PM the magical rodie...he'll be able to answer your questions. You can find him in the sticky at the top of this section.
Dan McLean Jr aka, Magic Roadie
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Hi, Seth!
I don't know the answers on this one. Since this isn't a magic question or an audio question, I suggest this isn't the best place to seek help. You may get an suitable answer here ... maybe not ... maybe you'll have to sort through the answers and figure out which one is right, or most right. I think you'd be better off asking someone you know will give you the right answer. An experienced, licensed electrician might be a good bet, and I'm sure other pros would also be suitable.
Good luck, Seth!
Dan.
Dan McLean Jr
sethb
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Hi Dan -- Thanks for chiming in here. I've already poked around on the 'Net a little, and have discovered that there is such a thing as a DC/DC converter, which provides a regulated source of DC current at various voltages. It is apparently meant to be connected to a cigarette-lighter type connection at one end and a pin-type (coaxial, I have learned, is the right word) connection at the other end. My next stop will be Radio Shack, to see if something there might be useful. I may even find a salesperson who knows what they're talking about!

I also discovered that something very similar is already available for the Fender Passport PA systems, a DC/DC converter which permits the PA to be run from a separate rechargeable battery, click HERE to see it.

So apparently I'm not the only one to have pursued this line of thinking -- I must be on the right track!! Now I just need to find out which train runs on this track!! SETH
"Watch the Professor!!" -- Al Flosso (1895-1976)
"The better you are, the closer they watch" -- Darwin Ortiz, STRONG MAGIC
Eldon
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Hi Seth,

First of all don't assume that the AC converter is converting to 12VDC, make sure. The converter usually is marked with input and output voltages. If it is 12VDC out, then you are on the right track. Radio Shack can sell you the cigarette lighter plug with the right connector. Just make sure that the polatity is correct and you should be good to go. Actually the DC voltage from your Xantrex is pure and should work even better than the ac converter. Make sure you take your Paso with you so they can match up the plug.
sethb
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Eldon -- Thanks for the caveat, you were right.

I checked and the PASO AC/DC converter gizmo says that it outputs 15 volts at 4 amps, not 12 volts. The DC input on the PASO unit says it takes 12-15 volts at 4 amps. And the diagram on the gizmo box says that the center pole of the coaxial output plug is positive, so now I know that, too.

Now we will see what Radio Shack does with all this info. I see that they do sell a "high-power" DC/DC adapter (#273-1818) that says it will handle from 4.5 to 12 volts, but it doesn't specify the amperage. It has a CLA input plug and a Barrel output plug, whatever they might be; hopefully it's a cigarette plug on one end and a coaxial plug on the other.

I agree that the DC from the Xantrex should be better than the converter, because from what little I remember about electricity at all, DC is linear and doesn't have "waves" like AC current does (I guess that's why it's called alternating current). One thing that also occurred to me -- I am assuming that this is a one-way electrical street, that the electricity will "know" to go from the storage battery to the PASO unit. But is there something that keeps it from going the wrong way? When the external battery gets low, what prevents the PASO internal battery from trying to recharge the external battery instead of powering the unit? I know water always runs downhill, but I'm not sure about electricity.

Finally, I can't believe I have to figure all this out just to sell a bunch of Svengali Decks and Money Paddles!! In fact, why didn't electrical instructions COME with my Svengali Deck? <grin> SETH
"Watch the Professor!!" -- Al Flosso (1895-1976)
"The better you are, the closer they watch" -- Darwin Ortiz, STRONG MAGIC
TV Magic Pal
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Electricity is not a one way street at all. It's more like water flowing to the low points!

Why don't you contact PASO and see what they say about external batteries. There are often really good reasons not to use them. I don't want to complicate things further, but there are different kinds of batteries and certain devices prefer one type over another (ever put non-alkaline batteries in a digital camera and discover that they last about 10% of the time alkaline batteries will run?).
Michael L.

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sethb
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Michael -- Good point. In fact, I sent an e-mail to PASO tech support about a week ago, but unfortunately haven't heard from them. Maybe they're still researching it? I'll give them another try by e-mail, or maybe give them a call.

I have found that the PASO uses a sealed lead-acid battery, which is the same thing that the Xantrex unit uses, for what that might be worth.

BTW, the battery capacity of the PASO is very good as far as it goes, I have no complaints on that score. Any unit that will run for 4-5 hours continuously on one charge is doing pretty well, and who usually performs longer than that? But when you're pitching Svengali Decks, it is usually a 6-7 hour proposition, and so that's why I need the greater capacity. I'd much rather plug into an AC outlet and forget about it, but I don't often have that luxury. SETH
"Watch the Professor!!" -- Al Flosso (1895-1976)
"The better you are, the closer they watch" -- Darwin Ortiz, STRONG MAGIC
TV Magic Pal
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Most tech support in the industry now (unfortunately) is on a 3-8 week lag!
Michael L.

Magic is a lie. It is our job to convince the audience to overlook the lie and our goal to make them embrace it.
Dan McLean Jr aka, Magic Roadie
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Quote:
On 2007-05-21 22:38, TV Magic Pal wrote:
Most tech support in the industry now (unfortunately) is on a 3-8 week lag!

Specifically, with which companies are you experiencing a 3-8 week lag? In the past couple of months, I've called Shure, Sennheiser Canada, Sennheiser International (Germany), Lectrosonics, AKG, Countryman, Digidesign, Yamaha, and E/V, and all have helped immediately or within 24 hours. I don't recall any experiences longer than that.
Dan.
Dan McLean Jr
TV Magic Pal
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Mackie and it's cronies, Fender, a few others lately. There is someone there to answer questions on operation, but for anything not in the user's manual there is a lag because very few companies have technicians in the country. Anyway, I pulled that number from an article a friend sent me a couple of weeks ago from one of the industry rags.
Michael L.

Magic is a lie. It is our job to convince the audience to overlook the lie and our goal to make them embrace it.
createch
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Tell me exactly what you want to do, and I'll tell you how to do it. What is the voltage, and current rating in amp hours, on the present battery? How long does it run before it goes dead? How long do you want it to run? Repeat the charger rating again.
"Building electronic effects for magicians and mentalists for 30 years." We repair Anverdi items.
sethb
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Hey Createch, I much appreciate the offer, thank you!

But since the time I posted this thread, I found an easier and simpler way to accomplish what I wanted, using a secondary INTERNAL battery wired in parallel, instead of an extra external battery and an adapter/connector. Click HERE if you're interested in seeing that solution.

Actually, I'd be interested to know if you have any thoughts or comments on the internal battery solution; that would be appreciated too, since I'm still sort of in the dark on this stuff. Perhaps there is another, even better way to do this? SETH
"Watch the Professor!!" -- Al Flosso (1895-1976)
"The better you are, the closer they watch" -- Darwin Ortiz, STRONG MAGIC
Father Photius
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What you need is a capacitor across the output from the rectifiers (what converts ac to dc), the capacitor will smooth out the sine wave for you , it is a filter, and will cut out any ac hum. But let a qualified electronics tech make the conversion for you so it gets in the right place.
"Now here's the man with the 25 cent hands, that two bit magician..."
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