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Old March 27th 06, 09:01 AM posted to rec.radio.amateur.homebrew
John Wilkinson
 
Posts: n/a
Default Connection for clock distribution

On Sun, 26 Mar 2006 21:19:01 GMT, W3JDR wrote:

The author said it was RS-485. This is a 2-wire differential signalling
system. He also wants to use a shield. Hence the need for 3 circuits. I
doubt that reflections will play any part in the performance, especially
considering that he's using twisted-pair for the signals. This is how CAT5
RS-485 distribution works.

Besides, he's talking about a1 MHz presumably steady-state square-wave clock
and presumably short board-to-board connection lengths.


Joe
W3JDR


"jack" wrote in message
...
Problem with a phono-plug and a clock signal is that you will get
reflection
back -- probably much better off with a BNC or SMA connector.

"W3JDR" wrote in message
news:NXhVf.9224$6%2.4606@trnddc08...
John,
How about a miniature stereo phono plug? These have 2 signal circuits
plus

a
ground. They're common, they're available in many PCB configurations, and
they're cheap.

Joe
W3JDR


"John Wilkinson" wrote in message
news Hi,
I have a 1MHz clock that I need to disribute to several boards. I am

using
RS485 drivers and receivers to do this, along with twisted screened
cable.

The question is that I need a 2 pole pcb connector that is screened.
Does anyone know of such a beast?

Thanks,
John.





HI,
Yes this is a differential signale, so needs 2 connections plus ground for
the shield.

I have looked for these stereo phono plugs, but to no avail, any idea who
stocks them, RS/Farnell numbers.

Thanks,
John.