make your own I/O cables

The cable you link to has a pretty confusing picture, but I am guessing from the description that this is the stuff that when you strip the jacket and unroll it, it works like regular ribbon cable. if you don't need the compact nature or shield, ordinary ribbon cable is a lot cheaper. You can crimp the connectors in a vise. You may want to get the strain relief pieces for the connector, they help the connection to last longer.

Jon

If you're only doing a few check Digi-Key and Mouser -- they may have better price and availability on small quantities.

Depending on how you're going to use the cable you may also want to get the strain reliever and the pull tab. The strain reliever loops the cable around the back of the connector so a tug on the cable doesn't pull on the connections. The pull tab is a string or a loop of plastic that goes under the strain reliever and lets you pull on the connector body without upsetting the connections. Decent computer cables use both

-- the one for when you pull on a disk without remembering to unhook the cable, the other for when you unhook the cable.

To stomp the connector on the cable you want to align the cable on the connections, then press everything together with a pair of flat and parallel somethings. Different connectors differ in detail, but most of them let you put the connector together "one click" (or ship the connector that way), which allows just enough room to put the cable in and inspect to make sure that the tines of the IDC connector are lined up right. I hold the connector lightly in a portable vise, then get the cable put in so that it looks good, then tighten the vise. Amphenol will sell you a special tool to do this, it costs about a bazillion dollars, and to my knowledge doesn't work any better than a vise or an arbor press with the right set of jaws.

To be thorough, check the cable to make sure that each wire is connected from end to end, and isn't connected to it's neighbors (i.e. check pin

11 against pins 10 and 12). You can reduce the need to check, and increase the reliability of the cable, but sticking to name-brand hardware like Amphenol or 3M (I have never, ever gone wrong with 3M).

Make sure that you're connecting pin 1 to wire 1, and that the wire exits the connector on the correct side (check twice if you're using strain reliefs, as this swaps the side of the connector that the wire exits from).

>

Additionally, last I looked, Digi-Key had these cables available pre-made in standard lengths and possible custom lengths as well.

That cable URL mentions bulk termination but it isn't clear how far apart the flat sections are, where you can attach an IDC connector. Consider plain flat cable like at following URL, if you don't need round.

Do you actually have to make the cables yourself? Standard SCSI 1 and SCSI 2 cables with 50-pin IDC connectors aren't expensive. See

(URL on one line), , and .

> >

Thanks, everybody, for the advice. I hope i didn't miss it on digikey. I used the flat ribbon on my last refit and its an awful mess plus not sheilded. Another fella that does camsoft refits suggested this. So, i just dropped two bills on a lifetime+ supply.

Karl

Karl

As another said this will probably be a standard ribbon cable for you. half the conductors are simply drain/grounds/shields in between the signal wires. IOW the usual ribbon cable for interconnecting floppys and hard drives in you computer.

So how long do you need the cables?

Bob AZ

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, and

Damned good price, wish they were longer. I'll keep this link for other's doing a camsoft refit. Thanks karl

You just gave me a great idea. I'll get four short ribbon cables and make a holding bracket on the side of the computer. The I/O card plugs the cables directly and they are a PITA to disconnect. This will get it outside the case. But, now I'll have to look for a male connector, surely no big deal.

My runs will be from six to eight feet. They are alongside a lot of other wires, so sheilding and round are important.

Karl

karl

Don't count on that, but good luck!

This may seem very basic but I have seen it ignored.

Ribbon cables are very fragile and should never be used "outside the box". They are great between fixed components, eg. disk drives inside computers but it does not take much physical activity to fracture a wire or 2.

Take a look at the cables that Karl is buying, though -- as long as you take care to nail down the round part with respect to the header on the board I think this cable will be as robust as any other light duty "outside of the box" cable.

But yes -- normally ribbon cable is a disaster waiting to happen if you stress it too much.

Yea, I've been surfing digikey for over 1/2 hour and can't find one. maybe i don't know what to call it.

Karl

>> >

Being a former engineer for the company that used more flat cable than anyone else in the world that we knew of. System Industries and we were the largest 2nd source for disk subsystems for DEC. You can install the IDC connector with a vise. Just be careful that the cable is lined up correctly. Some of the connectors with the metal end tabs were a little easier to line up.

He probably wants to keep them. ;-)

Cheers! Rich

Assuming you're going to a PCB, look up "header".

Good Luck! Rich

Depends on how ham-fisted your customers are. I once worked on a commercial product that had 24" ribbon cables out the back with a DIP plug at the end.

They're OK, as long as you don't use them to tow a car or whatever. ;-)

Cheers! Rich

From what I remember there are male to male adapters that fit between female ends of ribbon cable connectors - ore used to be.

But CalesOnLine has Item # FC-150 for $250 each. Computercableinc has them for $7.50 each. Part # CON-IDC-50M

50 pin male idc connector - don't know if Digi carries them but I just posted 2 sources - one very reasonable, the other moderately pricy, but certainly not bad compared to what I remember paying for themabout 30 years ago!!!!!!!

Not sure what I'm looking at. Either of these right?

Karl