>
>
> With +/- 12VDC RS232 drivers, I've done 800' and 1000' runs
> of Cat5e @ 19.2Kbps without issues.
>
> {On the other hand, on cables designed for RS232 decades before Cat5e,
> I've had issues at one tenth that far, (~100pf to 200pf / meter)
> at 19.2Kbps.
>
>
What I may have is "self interference" of some kind. Most of the pluses
get through just fine. A few don't. Perhaps the Tx wire is close to the
PPS wire. I wonder if sending data at 9600b could effect the signal on a
parallel conductor? When I look at the logs, I see the error is almost
periodic. I've noot looked really close but the errors do seem to be
equally spaced. I saw this kind of thing once at work and it turned out
to be an air traffic control radar a couple miles away. I doubt this is
the case now but I do have ASCII in the same cable
Your test that you can send data over cat-5 is not the same as sending two
streams of data over cat-5.
I'm sure I could fix this be using diferenctial drivers on a twisted pair
but I think moving the computer is the best plan. Then the PPS will be
sent over RG58 coax and level converted just inches from the computer.
Chris Albertson
Redondo Beach, California
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