Pertec Interface Cable Length

Glen Slick glen.slick at
Sat Aug 10 12:22:08 CDT 2019

On Sat, Aug 10, 2019 at 9:46 AM Douglas Taylor via cctech
<cctech at> 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.

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