In calculating cable run losses (that I have constructed) I use the figure of 0.5 dB loss per connector. Perhaps somebody makes them better than I do, however. (HI)
73, John - K8OCL
----Original Message Follows---- From: "Nate Duehr" [email protected] To: [email protected] Subject: [amsat-bb] Re: Feed Line Loss @ Freq vs. Price Date: Thu, 10 May 2007 13:46:35 -0600 (MDT)
This is true. However, the connectors you must put in line from past the rotator to regular LMR-600 to the station would likely eat up all the delta in loss!
To continue the thread accurately - we now need to know how lossy specific connectors are.
All of these "runs" described so far are about 40', a "typical" number for a small tower or structure many hams might have... but if you're running 100' up a tower or structure... the clear winner starts to emerge...
1/2" (or bigger!) hardline with a short jumper of something flexible at the top and high-quality N-connectors at that junction.
Right? Feel free to do the math... if you can find real world numbers for connector losses that you trust.
Also keep in mind if you ever plan on "re-purposing" any of the cable runs up the tower for duplexed service (going to put a repeater on the tower via one of your runs of cable), LMR is a very VERY poor choice for duplexing... its design leads to noise and desense problems. Not a problem in non-duplexed service, though.
-- Nate Duehr, WY0X
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