Anyone know a way to calculate energy consumption?

[KisskerVenwrath]

Alright without giving too much away (spoilers, tsk tsk) I am trying to figure out the power consumption of several devices "not normally hooked to small batteries".

I understand voltage pretty fine, I mean 1.5v + 1.5v = 3v so 2 "AA" batts plus a "9v Square" = 12v of power.

The problem comes to wattage used and how long those said "12 volt battery" will last, if it will power at all.

I am also diving into the realm of Audio equipment which brings up a whole bucket of fish I've never thought about before. So help is greatly appreciated.

The goal is to get a set of speakers and any required devices needed to run those speakers (amp, etc) running off a smaller - lightweight and portable battery.

I went to Best Buy, because the "Audio Dudes" there are about the best around where I live, they suggested some combo of a Micro Amp and some small 2.5'' speakers for my specific function - using an MP3 device to provide music/radio through the set.

This is all fine and all that, except the $200+ price tag on those items. So I got to thinking "there has to be a easier way."

Computer speakers popped into mind - but - I do want the sound to be Crisp, Clean, and decently Loud, which is where I have come to an inconclusive result.

Is the Amp really needed? I mean I can take my 2 desktop speakers and plug them into my MP3 and it plays just fine - no Amp there - but they don't exactly get "loud and clear" as I am trying to get to.


With this in mind I also have a video construct with a similar problem, lots of "wall adapters" and no real information on "how to make it portable".

Got a 0.01 Lux "night vision camera" I want to combine with a 3.5" LCD monitor and make my own set of nightvision camera gear for example, hard part is, the 'monitor' using <=3W of power and I forgot what the camera uses, plus the IR LEDs to provide ample night vision usage, and a further problem on how to "capture and record" this information since the camera isn't a "handy cam" or anything - but a micro security camera. There is no media recording device to save to.

After all the power consumption is taken care of - I still have the problem of wiring. Don't want to burn out or damage anything after all.


So back to the basics:
Power for Speakers/devices to provide Clean and Loud music (although not heavy Bass - the device would shake to death)

 

[Arketh]

Any computer speakers that are powered have an amp built into them. That's actually the reason that they're powered.

Trying to get a loud sound out of a MP3 player will require some sort of an amp. They're not usually geared towards driving larger speaker setups.

The standard portable speaker systems for MP3 players aren't going to be powerful enough? Or is it that you're trying to get maximum life out of the set up? You can get them relatively cheap, just not sure of the results from them.

Either way, battery life is always a trade off with size. The smaller the battery, the less total capacity and longevity it will have. A single D battery will last 10 times longer than a single AA battery. Or, alternatively it will at least power a higher current draw for a useful time.

 

[nstevic01]

If I remember my Radio Shack days correctly, it's based on amp hours.

For example: a 12 volt 2amp battery will run a 12 volt 500mah device for 4 hours.

I have acutally found that R/C car batteries work nicely if you can keep voltage to 6v, 7.2v or 9.6v. Most of those will have 2-2.5 amps of power. Then you get into NiMH vs. NiCad:

NiMH will not have the memory effect of a NiCad, however it's power curve is sloped. Meaning, as it dies it provides less voltage.

NiCad has the memory effect, but will put out full voltage until it dies.

 

[exoray]

Well you really need to be more specific, total overall size, battery requirements (type and available room), would be a good start... Also focus on one device at a time, you jump from speakers to night vision camera and offer no specs for the devices...

For the audio get an older cassette boom box, put batteries in and you get a decent volume from batteries in a nice rugged already built enclosure without screwing around...

For the camera get a spy camera with a memory card, but the time you cobble yours together you would have saved time purchasing an already done unit...

And as has been said battery life is measured in Amp hours, so you need to measure all your devices Amp pull @ the batteries voltage and simply work the math... You said "<=3W" that is only half the equation 3 Watts at how many volts? 3 Watts @ 120 volts is 0.0180 Amps but 3 Watts @ 12 volts is 0.1804 while 3 Watts @ 5 volts is 0.4330 Amps... If you need to convert the battery to a higher voltage say a 12 volt to 120 volt converter you can expect about 20% lose (yeah I know they claim better conversion but 20% is generally safe in the real world)

 

[epilepticsquirl]

Is the Amp really needed? I mean I can take my 2 desktop speakers and plug them into my MP3 and it plays just fine - no Amp there - but they don't exactly get "loud and clear" as I am trying to get to.

I think you answered your own question here.

Rather than re-invent the wheel, why not just buy a small radio/boom box? With all the options and doodads now a days, an Auxillary audio port is on a lot of portable stereos.

As for nightvision, you're better off getting a cheap camcorder and modifying it to see only IR Light. Then wire up several IR LED's.

This guy is kinda annoying, but you get the idea:
YouTube - How to See in The Dark!

 

[KisskerVenwrath]

I think you answered your own question here.

Rather than re-invent the wheel, why not just buy a small radio/boom box? With all the options and doodads now a days, an Auxillary audio port is on a lot of portable stereos.

As for nightvision, you're better off getting a cheap camcorder and modifying it to see only IR Light. Then wire up several IR LED's.

This guy is kinda annoying, but you get the idea:
YouTube - How to See in The Dark!

Sorry for delays, my PC keyboard finally died after about 10 years of use and I had to get another for anything to work out Lol.

alright looking more into this as I go along - as for the buying a little boom box or whatever - I don't plan to keep only 1 suit. Building in a small Radio/boombox or whatever is nice and easy and all that -but won't allow me to put MP3s of my own on there or anything - and when the suits just on display like a statue - it isn't really gonna go to good use.

Using "break away" type design of cables, however, I can set up a Mp3 player and even the speakers to Pop in/out as needed leaving only the cables themselves. Essentially putting a bit more investment into full customization and allowing it to be easily transferred into another suit as I feel the need.