Portable Wall Sockets

Are you saying the transmitting part only has an ac adapter, and you want to run it on battery power from your backpack? If so, get you some c cell battery holders to ( two: 4 cell holder ) and connect them is series so you have + and - between holders. Also get a plug that matches the wall wart plug. Note what part of the plug is the possitive and match that with the battery pack. The transmitter will work from the battery pack ( 8 1.5 volt cells = 12 volt) same as the wall adapter output. You can use aa cells, but c or d cells are better. JTT..

Seems to me you know very little about electronics.

You want a new one?

Maybe, but is their something really wrong with his advice?

I'd point out that battery cells are usually rated in amp hours, and confusing that rating with the ampere rating of the transformer would mean the unit would run for about an hour, but this may not be the end of the world.

If there's a serious oversight, it might be checking if the power supply output is AC or DC, but again, there's a moderately good chance of getting away with that oversight. I can think of a case where marketing designed an automotive version of a product, replacing the

12vac adapter with a cigarette lighter cord. Engineering dissaproved, since the average voltage would be too low and the peak voltage spikes potentially to high, but it did sort of work, though with a greater tendency to distortion.

Hey, thanks, but now I have questions.

1- How long will this last me? 2- Can I get rechargeable C or D batteries? 3- Can I get a cheap recharger for them? 4- Where do I get the equipment to make this?

Thanks again! This is what I needed!

Also, I just rememberd that I was thinking about how those flashlights you shake and then use work. I was wondering if I could make one of these for 12V? Thanks again

robert baer, screw you. what i was saying would work, i dont know much about electronics, but at least i offer help, not put people down. i know a fair amount about electronics, but for some reason i never have bothered with batterys, as a kid i used to read something about amps, and thats how i got the idea, i design electical systems for cars, that includes the efi unit, i know enough to suit me, so f*ck you ass hole.

hey romanian im not 100% on this but i beleive those flash lights charge a capasitor and the light is an LED and they barly use any power... i dont think something like that could power something like that

Forget the flashlight shaker. I was also thinking, look into a sealed lead acid battery to make it last probably 2 days if its low power. What are the current needs of the transmitter? Also again if you go with sealed lead acid, get an inline fuse to connect at the battery ( just in case, dont want the fire trucks come to put out your back pack) :) Let us know your amperage needs of the transmitter and we can size the battery you need. JTT.. KF4HUF

Alright guys, thanks for all the help! I'm gonna run down to Home Depot tomorrow afternoon and get me some batteries! Thanks again guys! And yeah, thosewhohatedemectragio;haiohfgd or whatever your name is..... I think you're right about the flashlight. I found one in my attic, it's pretty small-scale. Thanks to all!

Hmm.... screw my last comment, I didn't see James Thompson's. The AC-DC converter says "12V DC, 150mA". I'm guessing that the 150 mA is the amperage needs? And what do you mean by by sealed led acid (I will tell you that I'm just 15, a sophomore in high school... I don't have much access to Potassium Sulfate and Nitroglycerin or any other crap that you might have if you work in a lab.... and I don't have much money either)? If there's a way to give simple step-by-step instructions to make some portable thing with rechargeable batteries so I can keep using them, that would be the best choice. If not, I could try and follow your instructions of "I will put the ownage powder inside of the tube and you will get uber headphones" and will probably blow myself up.

Step-by-step instructions possible? Thanks

Yes. When posting from googlegroups, DO NOT click the obvious "reply" link at the bottome of the post you're replying to - click the "Show Options" link near the header, then click _that_ "reply" link. This will quote context. Then trim appropriately, and bottom-post your response.

What exactly is it you're trying to accomplish? Please be specific. It sounds like you have a wireless headphone with a transmitter that plugs into your CD player, and you want to make the whole system portable. To do that, you'd need to buy or build a battery pack of some kind, or maybe two, depending on what you've got now, i.e., do the CD player and transmitter use separate wall warts? that sort of thing.

Try and draw a word picture of what you actually have, in as much detail as possible - even ASCII art could help; and what it is you're trying to accomplish, again is as much detail as possible.

Good Luck! Rich

Sealed Lead Acid is a Rechargable Battery Like what a car uses, but sealed so it wont leak acid. Robotics people use them as well as emergency lights and the good old Battery backup we use on our pc's. With only needing 150 ma, you could get by with using 8 c cell battries and it will last quite some time. For low cost try out the alkaline c cells. Do you have a volt meter to check polarity of the plug? Jtt...

Rich: I have a transmitter from the Sharper Image, which uses a 150mA,

12V DC plug/ It also has L-R audio inputs, which fuse into one headphone jack and connect into an audio device. The only thing that is not portable is the transmitter, seeing as it needs to be plugged in. I want to make a type of battery pack or something that hooks up to the transmitter instead of having to plug it in. This would allow me to take it everywhere I go.

By the bye, what is a wall wart?

And yes, I do have a volt meter. But my preference towards batteries was to use rechargeables so as they would "never" run out and I could recharge them at my every whim. Is it possible to get these batteries in rechargeable form?

Thanks again,

OK, you need 12 VDC. You do that with eight 1.5V alkalines - I believe you can still get battery holders at Radio Shack:

It's that black box that plugs into the wall socket (hence, "wart") that gives you your 12V, 150mA.

Then you'd use probably NiCds, or you could get a 12V gel cell - you can get one of those almost anywhere:

Good Luck! Rich

Oh, yeah, and please learn to post properly from googlegroups: Don't click the "Reply" link at the bottom of the text, click the "Show Options" link up in the header, then click _that_ "Reply" link. This quotes context. Then, trim appropriately (excise nonapplicable material) and put your reply at the bottom.

If there are several points you wish to respond to, then interleaved posting is acceptable, as long as the natural flow of the thread is not interrupted.

Cheers! Rich

Okay, I understand what you're trying to do, and I'm not going to offer any more advice on that since it's been done. However, isn't a CD player already portable? If you're carrying the CD player with you anyway, why do you need to use wireless headphones?

May I suggest a different approach? It will not cover 150 meters and the sound quality may suffer, but it is much easy.

Buy a "radio headphone", I mean a headphone with a built in FM radio receiver, and a battery operated FM transmitter like those used to channel music from any device into your car radio. (I have one that runs for months on 1 AA battery.) They are both quite inexpensive. Use those when you are roaming outside, leave the other one at home.