Power supply

**joey7415963** · 05-03-2009, 04:04 PM

Hi all, been a long time since I've visited these forums.

I finally decided to get this laptop into my car, and bought an official compaq car DC-DC adaptor. However, it is the wrong connection for my laptop, so i decided to see if I could merge the existing power supply adaptor to the new in car power supply.

I hacked apart the cables and found that my laptop runs off three wires, one at 18.5V the other at 14V and the other a ground, whereas the new supply has simply 18.5V and ground (both are rated at 65W/3.5A).

I am thinking of making a voltage divider (two resistors in series). Firstly I want to know if anyone knows the what the current will be at both pins (my fuse has blown on my multimeter), and secondly how I would control the current through the voltage divider, or will it just draw the current it needs?

My electronics is mega rusty so any help would be greatly appriciated.

Regards

**FusionFanatic** · 05-04-2009, 10:16 AM

have you tried to just connecting the 18.5v and ground wires and leaving the other wire disconnected?

**joey7415963** · 05-04-2009, 04:12 PM

Yeh thanks I tried that with the original power supply but it does need it.

I should have updated this sooner, I bought an inverter instead, seemed the simplest way to do it besides it was only £20 from maplin.

Next problem im facing is trying to get an aux input on my blaupunkt headunit, I don't want to take it out but all the methods I have tried have failed

Thanks for the reply though!