[amsat-bb] Clearance for Arrow II antenna when mounted?

Rick Mann rmann at latencyzero.com
Sat Dec 15 12:08:16 PST 2007

Hi. I have an Arrow II Yagi crossed 7x7 (440 MHz) and dual-band 3x7  
(144 MHz & 440 MHz). The manufacturer rates them at 10 W max while  
hand-held, but if I mount them, they're rated at 150 W max? I have an  
IC-910H, max 100W on 144 MHz and 75W on 440 MHz.

There are two scenarios:

1) On a tripod that someone will stand next to, and manually orient.

2) On a tracking telescope mount I have. My other concern here is that  
EMI will interfere with the telescope's on-board computer.

In each case, how far should I keep away from the antenna? Sadly, they  
don't publish radiation patterns. If it's manually oriented, I suppose  
I can have a friend run out to it when not transmitting, re-point the  
beam a bit, then run away before I transmit.

Any suggestions?



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