28 Feb
2002
28 Feb
'02
3:42 a.m.
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.