On Sat, Aug 10, 2019 at 9:46 AM Douglas Taylor via cctech <cctech@classiccmp.org> wrote: > > I bought the long cables off ebay, so they have to be good? Right? I > think the short cables came from a hamfest. > > The cables can be fairly long, I remember interfacing a TU80 to an > Emulex QT14 (maybe) and the DEC cables were round and about 15 feet > long. And it worked. > > It was too late last night to begin checking the long cables for > continuity, so I fired off the email instead thinking it may be a > termination problem. > > Is it possible for the IDC and Card edge connectors to be put on wrong? > You would want pin 1 to map to pin 1, and so on. > > Doug
If you build cables yourself without proper tools it might be easy to end up with bad results. It takes a fair amount of force to properly press a 50-pin connector on to a ribbon cable with even pressure. I picked up a used 3M Scotchflex 3316 manual hand press with locator plates for IDC and card edge connectors a few years back for a reasonable price. It made quick work of properly pressing 50-pin IDC connectors on to ribbon cables when I built some Pertec interface tape drive cables. I used some Amphenol Spectra-Strip Twist 'N' Flat ribbon cable and made a couple of cables that are about 8 feet long. I haven't had any problems using them between an Emulex QT13 controller and a Fujitsu M2444AC tape drive.