Dell inspiron 500m s-video output

Since my old Dell Inspiron 500m suffered a nasty accident the batteries don't work and it loses it's bios settings whenever it is switched off. What to do with it? Well my plan is to turn it into a media centre to record tv, play music, whatever. For this it should be well suited because:

It is very quiet
There is space under the TV for it, especially if I pension off the video recorder.
It has USB 2.0 ports for my Hauppauge TV Tuner (which has a remote control) and a big fast external USB hard disk.
Shouldn't take too much power: it can go into standby if the remote and the scheduler can wake it up
It has an s-video output.

Main disadvantage: DVD tray will be hard to access: not a problem if I use another computer and copy the files over the network.

The one flaw in this plan so far is that I cannot get the s-video output to work. I plug it into the computer and TV and nothing happens: no new options appear on the laptop to enable the TV output.

After extensive research I have discovered that the video circuitry in the laptop it looking for 75 ohm terminating resistors inside the TV when the cable is plugged in. I poked some 100 ohm resistors (nearest I had) into the s-video socket of the computer and hey presto, the TV output options appeared in control panel/display (a plug-and-play kind of thing, complete with bing-bong when you plug it, doesn't appear to need a reboot).

Next I cut the last 4 inches off an s-video cable and soldered in the resistors. I plugged it into the TV and, after some fiddling with the TV settings I had a picture. In black and white. Somehow, somewhere the chrominance signal is getting lost.

In Black and White it looks like it will give a pretty good desktop, it should be quite usable if I can get the colour working. I have played with the PAL/NTSC settings but that makes no difference.

If all else fails I will try this trick to make an s-video to composite adapter: the signal won't be as nice as pure s-video but it might be in colour.

Dell sell a s-video cable for the 500m for about £25, I could simply buy one of those but I'm too mean, I'll try to reverse engineer it.

Watch this space.

I found a neat trick to make a media server: install apache, expose your media directories and let apache's directory browser and http do all the magic. Nicer than messing with Windows Networking.

Update: I joined the two signals with a 500pf capacitor and joined the two grounds and it is now working. It seems that my 7 year old Toshiba 37 inch tv (so old it uses a crt) is expecting composite video on the s-video port instead of the conventional luminance and chrominance signals.

When I have time (i.e. not valentine's day) I will make up an s-video->rca phono adapter so I can plug it in round the back of the TV (the only s-video connector is behind a flap on the front of the TV). Then it's the small matter of running an aerial cable down from the roof so I can use the TV tuner. Meanwhile I can also record upstairs and stream the recordings.

The picture is not wonderful, there is noise which may be cpu or disk drive related. Hopefully a less bodgy cable will fix that.

Peter's Blog - Nodes for 500m

Dell inspiron 500m s-video output