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Entry  Thu Dec 10 13:10:25 2009, Alberto, Configuration, LSC, 166 LO Disconnected 
    Reply  Thu Dec 10 18:31:44 2009, Alberto, Configuration, LSC, 166 LO Disconnected 
       Reply  Fri Dec 11 09:30:09 2009, Koji, Configuration, LSC, 166 LO Disconnected 
          Reply  Fri Dec 11 11:42:26 2009, Alberto, Configuration, LSC, 166 LO Disconnected 
             Reply  Fri Dec 11 14:12:32 2009, rana, Configuration, LSC, 166 LO Disconnected 
                Reply  Fri Dec 11 19:51:13 2009, Alberto, Configuration, LSC, 166 LO Disconnected 
                   Reply  Sat Dec 12 07:36:56 2009, rana, HowTo, Electronics, How to Measure the Length of a Cable: Interferometry 
Message ID: 2402     Entry time: Fri Dec 11 19:51:13 2009     In reply to: 2398     Reply to this: 2403
Author: Alberto 
Type: Configuration 
Category: LSC 
Subject: 166 LO Disconnected 

Quote:

 

 Seems like very strange cable loss numbers. The Heliax is lossier than the RG-174? I wonder how these compare with the specs in the cable catalog?

In my last entry there was a typo for the measurement of the Heliax at 55 MHz. I corrected it. It was 1.084 dB instead of 1.084 dB/m.
For the Heliax I don't have the measurement of the loss per meter since I don't know the cable actual length.
 
Except for that, I checked the values I found on the Internet.
My measurements for the RG-174 seem comparable to the loss specified in the catalog (here): 6.6dB in 100ft @ 55 MHz, that is 0.22 dB/m, that compare with 0.155 dB/m that I measured.

I did the measurement on a 4.33 meter long cable with SMA connectors at the ends.

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