[vcf-midatlantic] WTD: PDP-11 tape drive?

Dave McGuire mcguire at neurotica.com
Thu Mar 7 22:11:13 EST 2019

On 3/7/19 7:07 AM, W2HX wrote:
> Thanks, Dave.

  You're welcome.

>>>    Just remove them and you'll be fine.  The "right"
> connectors for the Pertec 2-connector formatted tape interface are right
> there...take off that partial back cover with the DB25/DC37 connectors
> on it.  Each DB25/DC37 connector pair should connect to a single ribbon
> cable, which goes to a 50-pin IDC connector that's plugged into the back
> of the drive.  Unplug those, and there's your Pertec interface.
> Yes I did as you suggested. and you are right. Here is the rear of the unit with the back panel removed:
> http://w2hx.com/x/VintageComp/Fujitsu-2444AC/0306192310.jpg

  Yup, I've seen a few of those. :-)  (memories, memories!)  I've always
loved the M2444AC drives, and most of the ones I've been exposed to have
been on Sun systems, in the good old days.

> I see two 50 pin headers. I will have to check the docs for the QT13 (which I don't yet have) and I guess it has two 50 pin headers as well? Where does one find 50 foot ribbon cables with idc headers and what length should the be (or what would be too long)? I'll review the docs today and maybe it will have some answers here. 

  The QT13 has two 50-pin IDC connectors just like the drive.  The
maximum cable length is 25 feet.  Those cables are used for all sorts of
stuff; they shouldn't be hard to find.  I just make them when I need
them; ribbon cable and connectors are readily available.  There's
nothing particularly special about these cables.

  If you anticipate communication on the HF bands while running your
PDP-11, you might consider shielding the cable, though (almost) every
other line on those ribbon cables is grounded so the EMI isn't as bad as
it could be.

>  >>I'm pretty sure the technical manual for this drive is up on
> Bitsavers.  If you don't see it there, let me know, I have a paper copy
> that I can either get into the LSSM's scanning queue, or just let you
> borrow it.
> Thanks for the offer, someone has pointed me to the file on bitsavers so I should be good to go there.



Dave McGuire, AK4HZ
New Kensington, PA

More information about the vcf-midatlantic mailing list