handphone batt as power source

[paingod84 0]

i'm thinking of using old handphone batteries as power source for amp circuits, perhaps can be designed with caps as most of them are around 3+ volts to bump it up to 9v or something... anyone has any experience/thoughts on this?

 

i was thinking.... hey i've got some old spare (dead) phones lying around, and like they charge much faster as compared to normal AA rechargeables, and are pretty compact.

 

only problem currently is to build a proper socket (lest i figure a way of ripping the whole section out of the phone.)

[squalle 0]

then how are you going to charge it?

unless you're not talking abt Li-Ion batteries

 

Li-ion batts are not easy to charge.

bumping up the voltage is not easy as as to use caps only.

the result also arguably not very smooth DC

 

to integrate it into an amp circuit is the easiest prob among all

you can just solder some wires directly on the batt's pads. as simple as that

but doing that, you shd have on-board charger.

then again, like I've said Li-ion charger is not as simple as NiMH or any nickel based batts.

if you've got a lot free time and some money to spend, why not u experiment building one charger then teach me how to build one

 

another way, is to use ur handphone as a charger. but that's gonna be very troublesome as it involves another gadget

and the need of proper "socket".

the socket can be done. just that how much money are you willing to spend. heee heee

 

[paingod84 0]

well, yep precisely, the idea was to use the handphone as a charger. as in, all i gotta do is buy a spare batt for my current phone, one dedicated for the phone itself and the other for the amp.

 

building on board charger, no thanks lah hehe i'm trying to keep it as simple as possible.

 

what i've been doing of late is to hook up two wires into the back of my phone whilst i'm playing my guitar (the amp is a diy mini practise amp for my electric) haha. the phone works too at the same time tho i havent tried making calls hahaha.

 

point noted on the issue of using caps and how the dc might not be clean and constant, thanks, but ok lah meanwhile the amp seems to work fine on the 3.6V altho it sounds cleaner with higher voltage lah of course..

 

so perhaps i can just carry on with one batt direct..

 

oh this whole project is a $0 expenditure. all parts came from junk, and should continue coming from junk and not out of my pocket. the guitar amp was made out of one of those cheapo/free gift $10 speakers (i just cut the wall power supply off and hooked it up to my old phone batt and made my own cabinet for the speakers (the plastic case is super ugly and not portable enough cos i'd like to carry it around when i meet up with my band..

 

maybe i'll go ask relatives n friends for old spoilt phones and collect all the batts hahaha.

 

i'm damn cheapo lah. charging hp batts is way cheaper than buying 9v batts all the time. (or buying a proper 9v rechargeable.) (or bother waiting for a whole day for them to charge)

 

anyone has any ideas on how to make a socket for the batt? oh btw if it provides any reference well the batteries i'm using are the white nokia batts. (older models like the 3200, 8250) (just before the gray/black ones)

 

 

 

 

[nakedtoes 0]

why dun make a solar powered amp?? anyone good in electronic.. i need yr advices..

[thedoctor 0]

first thing to take into consideration is the voltage to be supplied. the Nokia batteries have only 3.6V of output. that barely runs anything other than the cheapo National chip used in the PA2V2. well maybe the AD8397 on the PINT could also be used. but judging that those needs 3V of minimum voltage, then i have to say that you have an awfully short run time.

 

well maybe one could use a DC booster. there's a few DC switching chips from Linear, Maxim and Texas that has high efficiency and could work all the way down to 1.5V. some are operating at 200KHz switching range that would most probably won't be audible when properly implemented. as in no switching noise.

even Xin's portable amp are using a DC booster chip to bump the operating voltage to 12V from 5.5V and 3V.

 

or you could run them in series and get higher voltage. but by then you couldn't use the normal headphone charger anymore. or paralel them and stick to a DC booster and have better run times.

 

but all in all, Lithium Ions are not exactly easy to work with. you need an overcharge protection and take into consideration of the ultra low impedence of the batteries itself. put too much capacitance in the power supply and most probably something will blow from the initial power-on rush.

 

needs careful consideration and design. for the hassles, i'd rather buy me a rechargeable NiMh 9V. but that's just me..

[jasonhanjk 0]

Agree on the 9V battery as source. It is by far the most simple in terms of charging, case up and availability.

[paingod84 0]

point noted regarding the difficulties involved in using Li-ion batts, thanks guys.

 

however, i happened to come across this,

 

http://www.bairesrobotics.com.ar/elektor/1...p%20Battery.pdf

 

but with no prior knowledge regarding electronics whatsoever, i'm totally lost.

 

so what can this little gadget achieve eh?

[jasonhanjk 0]

It uses a capacitor as a supply source, that's all.

[paingod84 0]

but is it viable for our kind of purpose, or is it more for lower powered devices like remotes.. etc..?

[huangyong 0]

why dun make a solar powered amp?? anyone good in electronic.. i need yr advices..

 

haha..nakedtoes, do you want to carry an umbrella with solar panel and walking around....

anyway this idea is interesting.. may be can try use ur shoe to charge.. kinetic energy..

[jasonhanjk 0]

That cap is mainly use as a battery source for MCU or other very low power devices. Since it uses a DC-DC booster, a lousy design will add noise into your portable amp.