# Transmission Line theory, please help! - RF Cafe Forums

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screamtruth
 Post subject: Transmission Line theory, please help! Posted: Thu Jul 01, 2004 3:08 pm
 Lieutenant

Joined: Thu Jul 01, 2004 2:58 pm

Posts: 1

Location: Channelview, Tx and World

I'm trying to learn transmission line theory on my own, a difficult task, as I'm finding out. Keep in mind, our sub sea control lines are balanced tranmission lines, and have lengths in excess of 10km. Now, first can anybody explain the losses, or attenuation of these lines? Is it just a function of the series resistance per unit length? Or, is it a function of frequency, impedance? Our test frequencies are LOW, I mean in the range of 1 to 3 kHz. Does surface roughness play a part in this? Secondly, I have no way to measure the reflection coefficient or SWR caused by the Well load on the opposite end. Last, I am trying to calculate the NVP for a specific conductor in which I know the Z,C,L values, is there an easy way to perform this? How does the formula for propagation constant play here; y=a+jB. y = prop constant, a = attenuation, and jB for phase shift.

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What? Huh?

KC2SHO
 Post subject: Posted: Thu Jul 01, 2004 5:43 pm
 Captain

Joined: Mon Apr 12, 2004 4:50 pm

Posts: 20

Location: South Florida

 I have some very good training materials in PDF format if you are interested. _________________

Posted  11/12/2012