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Resilient
06-24-2009, 08:15 PM
Ok, so I am trying to make a DIY projector for my TV on the cheap using an overhead projector and an old LCD panel from a LCD monitor.

I took apart the monitor and I am almost there but found that a ribbon is too short.

Its not this one, but its this kind (flat, brownish orange, with the circuit printed on it):

http://gsmserver.com/newshop/images/large/LCD_ribbon_for_Siemens_SK65.jpg

Would it be an entirely stupid and impossible task to try to cut it and splice wires between the two cut ends? Does anyone have any other ideas on how I might lengthen it? Maybe it would be better to totally remove the ribbon and ribbon connectors and solder directly onto the circuit boards?

Fine soldering unfortunately is not really my strong suit.

jes1510
06-24-2009, 10:12 PM
Cutting it will destroy it. There is no way to solder to the ribbon itself after it's cut. You might be able to solder thing (around 30AWG) wires to the connectors on the end and then cut the cable but it will most likely melt.

ScuD
06-25-2009, 01:27 AM
Uh-oh... Lynn will have your head for that, Jes! ;)

It is possible to solder directly to the cable, but you'll have to scratch off the plastic layer exposing the copper underneath. That doesn't mean it's easy though. Since the 'plastic' is in most cases Kapton, you shouldn't worry too much about it melting, but you might want to try tapping the soldering iron to a non-critical part of it to make sure.

Now, I'm not saying this is easy. I have a fair amount of soldering experience, even hand-soldering BGA, but these things can be a pain.
With enough solder flux, a loupe, and some steady hands, you can achieve a lot.

Easier solution though is indeed soldering straight onto the connectors' solder pads with some plain ribbon cable.

Easiest solution is finding a replacement flex with the desired length, though these can be costly, if you can even find them at all.

Adrenalynn
06-25-2009, 02:32 AM
Or just build a board in between. Plug one end into the socket, and jump over to another socket that extends out on the appropriate ribbon.

Bullit
06-25-2009, 06:58 AM
Parlex makes these custom. You can often purchase a longer length on Digikey or contact Parlex directly and often you can get a sample of exactly what you need for free.