"Karl Townsend" wrote in message
...
On Thu, 21 Oct 2010 16:53:44 -0500, "Pete C."
wrote:
Tim Wescott wrote:
On 10/21/2010 01:49 PM, Karl Townsend wrote:
I need to make up cables with 50 pin ends, two rows of 25 on .1
spacing. I've never done this. Are the parts below all I need? Any
instruction on putting the IDC end on?
50 conductor cable
http://www.alliedelec.com/search/sea...y&Ntt=608-2905
IDC socket
http://www.alliedelec.com/search/pro...px?SKU=5182308
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.
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
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.