Gentlemen Guessing either you did not read the entire article By Kent-AWA5VJB, or misunderstood.
Kent was addressing a way to use a metallic crossboom with crossed yagis. For satellite I suspect you have them connected to produce circular polarity. Normal installation would require the end parts of the crossboom be non-metallic (probably fiberglass for strength). No metal should be closer than half-wavelength from element ends. So the only way to dress cable from the driven elements is draped off the backend of the antenna booms.
But Kent rigorously measured the effect of a metallic crossboom connection to the x-yagi boom to determine least interaction. The connection location on the antenna boom is critical but does allow running coax across both crossboom and antenna boom.
Being "cheap and Lazy" I decided to mount my satellite antenna using a metal crossboom with Yaesu B5400 azel rotator. I run my cables on the boom with tight corners to keep cables close to surface on the booms. Everything works well. I've not made field measurements so do not know how well they are working but was good enough for AO40, modes US and LS. http://www.kl7uw.com/sat.htm
Not currently RV for satellite.
73, Ed - KL7UW -------------------------------------- From: "Frank Karnauskas" [email protected] To: [email protected] Subject: Re: [amsat-bb] Attaching the coax to antenna boom Message-ID: [email protected] Content-Type: text/plain; charset="us-ascii"
This is quite curious.
Page 1 of the WA5VJB paper says, "Run the coax back down the antenna and along the boom keeping the radius small..." His hand-drawn illustration shows the feedline going down the boom then making a hard turn at the boom-to-cross arm plate.
The M2 instruction sheets for the 2MCP8A and 436CP16 antennas both state (in bold type), "Do not route feedline to boom to mast plate as exiting antenna here will adversely affect circular field."
Mr. Britain's paper is obviously focused on mounting the cross bar somewhere along the boom of a somewhat long antenna. The M2 instructions are for mounting short antennas from the back of the boom to the cross bar. Not the same situation. But, for a newbie like me, the definitive conclusion to this discussion is...I am still confused.
I was hoping to hang my M2 LEO antennas Monday morning but now not until after I call the M2 support line for their read on this.
73, Frank
FRANK W. KARNAUSKAS, N1UW
73, Ed - KL7UW http://www.kl7uw.com Dubus-NA Business mail: [email protected]