DEC BC09J cable

From: Jerome Fine <jhfine_at_idirect.com>
Date: Thu Feb 28 11:42:26 2002

>Tothwolf wrote:

> If you don't have an IDC press and this is the first ribbon cable you've
> ever made, buy at least 2.5x the amount of cable you think you'll need,
> and at least twice as many connectors. IDC connectors are somewhat fragile
> when pressing onto ribbon cable, and without the proper press, you end up
> damaging at least one before you get the technique down. Ribbon cable and
> IDC connectors are both inexpensive, so it would be good idea to have some
> extra. A vice and some small blocks of wood can press IDC connectors onto
> ribbon cable in a pinch. Don't try to press the connector on by hand, it
> won't work, and you'll break the connector. Also, don't use scissors to
> cut ribbon cable. It frays the ends of the wire, and can short out the
> conductors. If you don't have a flat cable cutter, (carefully) use a metal
> straight-edge and an X-Acto knife to cut the cable.

Jerome Fine replies:

I thought I might add a few observations about the cables I have made.

(a) I have worked only with 50-pin flat SCSI cables and the 20-pin/34-pin
cables for MFM drives or floppy drives

(b) I don't have an IDC press - I use a small vice with opposing heads
that are about 2 1/2" * 1/2" - I have never bothered to add wooden
blocks - the vice heads are undamaged and quite flat

(c) I usually work with USED materials, i.e. not only old cables, but also
salvaged header parts (connectors)

(d) I use a very sharp scissors to cut the cables - when I inspect the
cut cable end with a jeweller's loop, I can't remember when I have
found any frayed ends or shorts between the different strands

(e) Normally, I inspect the header parts (connectors) match-up to the
cable with a magnifying glass (sometimes even a jeweller's loop) just
before the parts are put between the heads of the vice

On a VERY few occasions, I have jumpered some of the strands
to each other when that was required. In a BA23 box with only
4 button switches, the READY line and WRITE PROTECT line
needed for a second MFM hard drive (RD52) were cut out with a
small X-Acto knife. Then I used the X-Acto knife to bare the
corresponding strand from the first hard drive. I then soldered the
two strands for the second hard drive to the corresponding strands
for the first hard drive. While I could not remove the WRITE
PROTECT status for both drives except by a re-boot, at least
WRITE PROTECT was available for both drives when required.

Toth, the above are not contradictions of your advice, just my
experiences when I did not know how to do anything at all and
used trial and error.
Received on Thu Feb 28 2002 - 11:42:26 GMT