×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Impedance Mismatch

Impedance Mismatch

Impedance Mismatch

(OP)
All,
I need your guidance in my problem following.

We would like to buy a communication cable to transmit the signal from signal source to the final actuator. The signal transmitted by mean of MODEM.

The distance from the source is about 23 km. We already have about 10 km cable, and we would like to buy the rest of cable.
I do have a cable characteristic of the 10 km cable. And i try to source the vendor that have an identic cable characteristic, but no luck.

I am notice that the signal may not transmitted correctly if there is impedance mismatch. As i am not an expert in this area, i need your guidance in this issue.

I am really appreciate if there is some guidance on how to ensure the cable that i will buy is ok or not.

Best regards,
RK
 

RE: Impedance Mismatch

You plan on transmitting a signal via modem through 23km of nothing but cable?

Good luck with that...

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Impedance Mismatch

The early atlantic telegraph cables were a lot longer than 23 km. And they were 'nothing but cable'.

So, it can be done. The problem may be what speed you need. If you need to transmit MB or kB, it may be a problem. But if you only need to transmit a signal to an actuator and if that signal is just on/off - then it is certainly possible without any modem. A small polarized relay and a DC signal is used for that purpose in many installations.

If you need a complete protocol and duplex signalling, a low speed RS485 link may be able to cover that distance if the environment isn't too noisy.

You need to hire someone that can help you with this.  

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: Impedance Mismatch

If only there was some sort of alternative electrical communications mechanism, one that could cover 23 km, but without needing cables or wires. Let call it "wireless"...

 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close