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View Full Version : Purchasing a good Parallel port cable


javeria
Wed 03 December 2008, 03:53
Folks,

for the first time builders - if you intend to buy a ready made PP cable then be aware - chk the resistance between individual pins in between the two ends.

The reason being that - I had bought a ready made PP cable and my router was missing steps (the one with servos) For almost 2 weeks I was not able to trouble shoot the problem.

Finally one of my friends suggested replacing the PP cable to a hand made one.

Resistance on the readymade one was 3 ohm and I made one with a 20 core 0.25mm dia which had a resistance of only 0.03 ohm,

and then voila the machine worked perfect!

SO folks again chk the resistance of the PP cable if you are buying a readymade one.

RGDS
Irfan

Gerald D
Wed 03 December 2008, 04:23
Irfan, did you have a bob, like the PMDX-122, on the end of that cable?

As I understand it, a good bob takes care of cable problems.

javeria
Wed 03 December 2008, 04:41
Yes G' I had the Mini IO from Tom(www.candcnc.com), but if the steps are lost before reaching the BOB then what the BOB can do :)

so its always better to chk and buy the PP cable.

RGDS
Irfan

Gerald D
Wed 03 December 2008, 11:46
There are some other things to check when buying a parallel port cable . . . .

Don't get those very thin ones - they might not have 25 core wires inside. A LPT printer cable does not need all the cores, but it may happen to have all the cores.

What we need is a straight through DB25 to Centronics cable for the PMDX, which looks like the old-fashioned printer cable, and which may indeed be an old printer cable if you are lucky.