How to make a power supply cable for a 10.5V 4.3A laptop OR how much higher voltage can I use

Question

Let me preface this by saying I've spent countless hours researching and learning what I can about electronics before asking this, and I cannot find a clear answer to this. So sorry if this seems like something that's been asked before- trust me, I've read everything relevant and I'm still lost.

I have a Sony Vaio Duo13 laptop/netbook/tablet thing, which I had given to me with nothing else, no manual, no cable etc. I've managed to determine it requires 10.5V DC 4.3A. My only problem is, it's absolutely impossible to find a cable matching that. The closest I managed was 9V 1.5A which is absolutely awful, taking about 24 hours to fully charge it. It also switches on and off (as in, the power will cut in and out every 10 seconds, give or take.) But hey, at least it kinda works.

I came into a 9.5V DC 3A Polaroid "audio/video apparatus"

It had the wrong size connector, so I replaced it with the correct one (not sure what to call them, the cable had the black one that seems to be standard here in Canada and my laptop requires the yellow one which is slightly smaller).

The polaroid cable is coax, and not understanding at first entirely how they work I cut the extra thing (regulator?) that's just before the connector off thinking perhaps there's two RF wires beneath. No, but then I learned coaxial cables often supply power, and it's okay to rewire them for that purpose.

So I spliced them, forgetting I had removed the other part, which might be my problem. The red indicator light on the middle-box part of the cable lit up when I plugged it into the wall. But when I plugged my laptop in, it went out and didn't charge. Is that where I went wrong?

Would it be easier/feasible to just make my own cable at the correct specs somehow? I have enough spare parts and cables laying around to scavenge from. How would I go about that? I should add I don't have any equipment for saudering etc.

And on that note, do I have any wiggle room regarding cables for varying voltage? As in, if the Amps were high enough what would my potential range of possible voltages be (such as 8-14V, as an example.)

Thank you for being patient with such similar questions so often! I hope mine can be more broadly applicable.

Answer 1

I'm a bit confused about exactly what you did. A coaxial cable generally has a conductor down the center encased in some sort of insulator with a metal braid wrapped around that. What is the 'extra' thing you cut off it?

Any way the sort of cable you use isn't that important. You're not trying to send data signals or anything. The voltage and current you're using is too low to really need anything special. So long as you're not using super fine wires it should be okay. A power cable with wires 2mm thick can handle over 7A.

The power delivery device is going to be your problem. If you need over 10V at 4.3A then a 9V at 3A supply is not going to work. It will either overheat and explode or it will detect that you're trying to draw too much current and it will switch itself off.