Re: busted link cable HELP!

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Re: busted link cable HELP!

On Tue, 30 Sep 1997 16:39:03 -0700, Corey Runge <corey@OZ.NET> wrote:

>Ok, I built the printer port link from the dirctions on ticalc.  It worked
>great but now when I try to transfer stuff it won;t work.  I run the link
>test and it does not work.  So then I disconneted the link cable from my
>wires coming out of the port thing ( with the diode's) and I run the test
>and it works.  I also tried the test with some of the wires connected but
>it still does not work, although twice I got it to work with only one wire
>connected but I could not do it again.  I'm using the cut cable that came
>with the calc and I tested to see if there was a short but there wasn't.  I
>have not made any changes to my computer so I don;t think thats a problem.
>Thanks for any help you could give me.
>Corey

I had to try a couple of times to get my cable to work.. The first
time, the reason was a mystery at first. I was using 3 conductor +
shield wire. The link would only work after I cut the wire really
short.. I think the problem was that the length of the wire either
caused too high of an impedence resulting in signal loss, or it was
picking up some sort of frequency that interferred.. The diodes were
all fine because it would work w/o the wire connected to the db-25
plug. I made the wire really shory, and it worked, but only for a
short while. This part is a mystery to me- It seems it works for a
little while, and then it has the same symptoms that you are having.
It'll work a few hours later.. Strange. (Can diodes overheat?... I'm
using 1N4148's) I dunno, I made another one using 3 conductor,
unshielded wire. I did a much better job soldering the diodes as well.
A good tip, is try to keep all leads as short as possible. Anyways..
In my original one, I connected pins 18-25 I think it was, to increase
the ground, at somebody's suggestion. This cable I only connected the
ground to pin 22, and I'm using unshielded wire. The wire is .. I
dunno, a few feet long, and the cable works perfectly fine, for HOURS
at a time.

Go figure.

Probably didn't help you out much, but maybe you might get some
insight from this.. hehe

Rolf
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