longer keypad cable

bytor95

I just bought the matrix orbital 4x20 LCD and also bought the keypad and cable. I have everything working so good I can't believe how great these products are except:

The connection cable is so short that there's almost no way to mount it in the same plane as the LCD without bending the heck out of the cable. Does anyone know where I can buy a longer cable that will connect to the 4x4 matrix keypad?

http://www.parallax.com/detail.asp?product_id=27943

Engin

D Faust

Try an online electronics parts store such as mouser or digikey. They should sell ribbon cable that you could solder in between the two ends. EX. original cable-new cable-original cable. This would involve sacrificing yuor original. You might be able to find the same wire and connector assembly. Or you could use ribbon cable and try to find the right connector.

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RDL2004

It looks like you need an 8 conductor (only 7 are used?) female to female connector with 0.1 inch spacing. These are not easy to find pre-assembled, it seems you're expected to make your own from pins, connector housings and wire. It's not that hard to do, but without the right tool, crimping isn't that easy or reliable. You almost always need to solder them also. And ribbon cable is usually only available in 0.05 inch spacing, this works fine for double row connectors with IDC fittings on the ends, but for single row you'll probably have to use individual wires. I did run across this:

www.allelectronics.com/cgi-bin/item/CON-88/189/2_8-PIN_CONNECTORS_W__HEADERS_.html

but it doesn't look to be much longer than what you have. There may be similar assemblies available from other suppliers.

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- Rick

Duffer

Try Molex SL 0.1" spacing connectors:
Mouser Part #s:
538-50-57-9008······· 8 pin female connector (or -9007 for 7 pin if you prefer)
538-16-02-0097······· Female pin for SL connector

Mouser online catalog, page 1,245··· Fig's ·F and K

I usually keep a good supply of the 4, 5, 6, 8 and 10 pin connectors and a·several·hundred·of both the male and the female pins. Custom cables are easy to make with the right connectors and simple hand tools and can really·save a lot of time and keep your project from looking kludged-up with multi-wire bundles for cables.

These pins aren't that difficult to crimp lightly with needle-nose plyers and then solder. If you'll promise not to laugh, I'll give you a good tip. Take a look in the jewelry making/bead section of a large craft/art store like Michael's.

http://www.michaels.com/art/online/displayProductPage?productNum=bd0350&channelid=

These are nice narrow-jawed crimpers that are·perfect for the molex pins of this size. And the price is very reasonable. Specialized crimpers listed on the· Mouser catalog page above: $116.00. If I remember right, the crimpers at Michaels were about $10.00. Also do yourself a favor and check out their other small hand tools while you're there. I think you'll be surprised at the price and the quality.

For the cable, you can use .05 pitch ribbon cable. Buy 16 conductor cable (you'll only use 15) and cut back· every other conductor about .25 - .5" (see below)· Gives you perfect .1" spacing and plenty of room to crimp the pins on the remaining 8 conductors for the connector. Buy it by the foot and you can make it as long as you want.

Good luck,·· Steve


Post Edited (Duffer) : 8/24/2007 6:25:46 AM GMT

RDL2004

I'm a fan of Molex SL connectors also. I'm going to have to try some of those bead crimping pliers. None of the cheap crimpers I have work very well, and I can't afford $100+ for something I don't use that often.



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- Rick

cyplesma

if you have some old long hard drive cables (32 or 34 wires wide) you can cut those with scissors, both length and width.

RDL2004

Steve,

The photo at Michael's of the bead crimper wasn't too clear. Do these look like about right?

Micro crimpers on eBay

Edit: I think those may be for wire size that's too small, but I'll check with the seller, these may be the better choice:

Bead crimper on eBay

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- Rick

Post Edited (RDL2004) : 8/24/2007 9:34:49 PM GMT

Duffer

Rick,

Those both look like the ones I have and those two on e-bay look the same to me?· I don't know the exact sizs of the jaw opening, but they have two "stations" on the jaw, the first is "O" shaped to close the little tabs around the wire, the second is more "B" shaped to put a good tight crimp on the conductor and the insulation. I only saw the one size of "bead crimper" in the store. That price sounds about right though.

Close-ups of mine below.

Steve


Post Edited (Duffer) : 9/5/2007 5:14:53 AM GMT

RDL2004

Thanks for pointing these bead crimpers out, I'd never heard of them before.

It's pretty hard to tell unless you look carefully, but the "micro" one has smaller cut-outs on the jaws. I went ahead and bought the non-micro version.

If nothing else, it's smaller and should be easier to use than this big clunker I've been fighting with:



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- Rick

Post Edited (RDL2004) : 8/25/2007 11:48:24 AM GMT

bytor95

Thanks so much for all the replies. I'll try most of your suggestions right away.

Thanks again!

Engin