thanks DA just the perfect thread i was after!! thanks

ive got a old pc sound system which is great, its got a built in amp, if i take the back off the subwoofer, (i have a feeling its 12v) with a transformer inside, then maybe i could use that??

my old pc line pc speakers, output after transformer is 8v, damn, ive run 9v speakers on 12v before but that was in my boat, rather do it properly in a motor

James, this is getting scary! A few weeks ago you didn't know where your engine was located - now you are taking mains-operated 'quipy apart...

Good on you

Ok, that transformer is outputting 8.5V AC - ie: the same stuff that comes out of your mains plug, and not what a car battery delivers. This could be good news as it might be more like 12V when rectified (turned from AC to DC), but it all depends on the type of rectification used. Ok, you don't need to know all that - which is just as well as I've forgotten most of it anyways.

What I would suggest you do is, trace the OUTPUT wires from that trannie (noting that the mains wire is the INPUT ones) and see where they go - it should be to a rectifier of some sort. This will be either be a couple or four diodes and a few other components. Hopefully from that you will be able to suss out where the DC output from THIS section is - there will be a large (probably blue) capacitor - and then the power wires heading off to the amplifier board.

Best if you take a photo or two, and we'll trace it from there.

Once identified, all you then need to do is (a) switch on the mains, (b) not electrocute yourself, and (c) measure the DC output with a voltmeter - which I hope you have? If you don't have a voltmeter, I STRONGLY suggest you get one as it's one of these things wot's essential in many situations. They cost peanuts - £5 for a digital one that'll do everything you need.

Post back - if you're still alive.

(Oh, can you show a pic of the speaker system, make, model, spec? It'll need to be reasonably decent to do the job in a car.)

DA ive always played with elctricity, ive never understood how its worked, but ive wired in sockets lights heaters, re wired psu's no pc's, have a old radio down at the workshop where i sometimes work, the radio blew up, so bridged a few connections on the circuit board



anyway pics
so from the tran it goes via 2 strand wire into the back of the sound control box
dc current loook


now when it goes in via here, it go straight onto a circuit board, so yer...



anyway its a cheap shit one, its pc line model number pcl-510
cost me about £25 big ones in pc world a few years back,

incidently, i bought another sound system which could go in the motor, its from asda apparently,

ill give you specs

duraband model no ht-3916

yes bought a multimeter, bought a decent one last week

Is the trannie you showed earlier located inside the same box as the PCB shown above - or in separate units?

So, it has a DC in socket too?! Does it say what voltage? Is it also 8V?

If you look at the last pic of the PCB, the large dark-blue cylindrical thing is the smoothing capacitor, and the actual DC voltage the circuit is getting will be found across its terminals. The four little black-with-silver-band things are the rectifying diodes - one-way valves, in effect. These are the little beasties wot turn AC into DC.

Anyways, if the DC input socket says '8V', or if you measure 8V as being the voltage across the capacitor when it's plugged into the mains, then I would suggest that it's quite risky to use this in your car as is. You will often get 14V across your car battery, and this is approaching double what this circuit was designed for. It might be ok - just depends on the tolerance (and safety margin!) of the components, but it's more likely that you'll end up frying the output stage especially if your turn up the vol high - which you will almost certainly do in a 2CV...

I'll try and get info on the 2 models you mention and see what I can find out about them.

no the tran is in the subwoofer box, so the 8v goes along a 2 strand wire into the pcb effectivly.

i looked on ebay for some, i dont want to spend loads if im honest, tight wad bastard tbh, but i would like a half decent one!!

thaks DA

^what he said^
i was in two minds and sort of halfway through the process of doing that and i think you've turned me

Me too!

Fair enough, chaps, but I do love my Radio 4.

(sound of shuffling as crowd slowly disperses...)