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Multi Function Device help needed, please! Answered

I've been toying with the idea of building a device incorporating several different devices, within one box - as small as can be practicably built.
Devices that I'm hoping to have installed are:-
(i) super bright led flashlight/torch
(ii) mono/stereo audio amp and speakers - 3.5mm input/output
(iii) built in re-chargeable battery (?V), with USB charge facility, wind-handle dynamo +(possible small solar cell?) - easy swapout to normal battery.
(iv) radio - FM/MW - anntena input needed
(v) emergency cell/mobile phone charger - USB to micro USB
(vi) internal USB type swappable memory, possibly with inbuilt MP3 support, linked to amp/speakers
(vii) clock/timer/temp guage
(viii) ANYthing else that can be built into a small unit!

has anyone else tried this kind of project? I have some (very rusty) electrical skills :) and would like to give this a try - but if anyone has done this kind of thing before, schematics and pics would be of great interest to me.

thanks in advance guys!



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Best Answer 8 years ago

To build something like this purely from scratch at the circuit level would not be the most effective use of time/money. However, it seems to me that most of the functions you want could be obtained by a off the shelf products.

So, if you bought suitable devices (hand crank flashlight, MP3 player, radio, clock, etc) you could then incorporate them into one system. This could involve some "hacking", to repackage the guts of each device within a new enclosure, and also to break out the necessary controls to a panel on the new controller. There may be some simpler custom circuitry and a fair amount of wiring to "glue" everything together. I could see it all fitting within a small enclosure, something like 2" x 3' x 6", depending on how large of a battery capacity you desire to built in.

Internesting idea...


Answer 8 years ago

Thanks LargeMouthBass,
I think I maybe thinking along the same lines:-
I have plenty of USB in/outs
I've got a micro radio
Ultrabright led's
spare wind-up flashlights

I think the major problem may be in configuring the connecting wiring - and switches!

cheers :)



8 years ago

Emergency radios, like THIS one, have everything except the MP3 player, and a some don't have a clock but if you have a cell phone that you're charging then that is redundant. The MP3 player is also redundant if you have a cell phone. Actually besides an amp for large speakers, an AM radio, and a crank your cellphone can provide everything you need and some. Find a cheap emergency radio with a usb plug and you're good to go.


Answer 8 years ago

Thanks bwrussell!
upon reading your reply, I realised how stupid i was being!
I've got a similar crank handle flashlight in my car - it even came with a bag of different connectors. It doesn't have radio, but my cellphone does - I just need a set of headphones for FM reception! I've got a spare 16Gb card I can pop in it too.
Problem side-stepped.
Many thanks!


8 years ago

Using examples from my favourite online china shopping site:

usb input lithium charger/protector: http://dx.com/p/mini-usb-1a-lithium-battery-charging-board-charger-144856

bajillions of led drivers (just switch power in and out)

Or just gut one of the bajillions of led flashlights:

click on/off switches

all sorts of unprotected lithium batteries (to use with that charger)

audio amp:

crappy fm radio mp3 player you could gut:


8 years ago

Everything your looking for short of an MP3 player, Clock and the ability to use the amp and speaker that comes with the radio side of the unit.