[amsat-bb] Re: Is it possible to work LEO sats (FM or SSB) with antennas in attic?

Mike Ryan mryan301 at comcast.net
Thu Dec 30 19:05:26 PST 2010

The Arrow isn't set up for mast mounting by default. But under the rubber handle (easily pulled off) is a threaded connector that mates with most camera tripods. Many use that tripod mount on the Arrow (including me) to manage fatigue and be lazy. You can rig up an L bracket with a trip to the hardware store that uses those threads and gives you something to mount to a mast. An L bracket connected to the Arrow on one end via the threaded screws and connected to a small piece of pipe, mast , or electric conduit on the other end through a couple ubolts. 
This would never hold up to wind outside but just fine in the attic. In this config 70cm is horizontal and 2M vertical but with a little creativity, you can flip that. 

Always having one band out of polarity is a characteristic of the Arrow. It’s a little inconvenient signal wise, but of you run full duplex, it gives you some isolation. The Elk, being a dual band log periodic, doesn’t have this feature and both bands are same polarity. Elk or Arrow. Always a debate in the group. Some swear by one and some by the the other.

Yes, keep that ARR amp at least until you get a chance to try it. It makes a huge difference on the downlink.  Better still if you have the “S” or switched model as its so very easy to accidentally pop your amp through a careless bump of the PTT.

As for the U100, that’s just my choice as I’ve been happily using them for years. Since the mast goes through the center, they also make a very easily deployed elevation rotor. Some good pictures of how to do that on Norms Rotor Service website. But you can use any inexpensive rotor like the Radio Shack (similar units available from NTE, Philips, RCA, and HyGain) . I have one of those too and its fine for light duty. Its just very clear by listening to it run and peeking inside the housing at the tiny motor that it wont hold up to punishment. The U100s may be ancient clunkers, but they are pretty tough.

Good luck.

Date: Wed, 29 Dec 2010 15:34:03 -0500
From: "Joe Krepps" <occupant at ytpress.com>
Subject: [amsat-bb] Re: Is it possible to work LEO sats (FM or SSB)
with antennas in attic?
To: amsat-bb at amsat.org
Message-ID: <op.vohsq1oraadv7j at joes-computer.local>
Content-Type: text/plain; charset=iso-8859-15; format=flowed;

Question: when mounting an Arrow to a TV rotator, are the 2m elements  
vertical, horizontal or ...?

Guess I better hang onto my bought-from-eBay-but-never-used ARR 432MHz  

Tnx & 73,
Joe WB3CFN <-now on the hunt for a good ol' U100 (Ka-CHUNK Ka-CHUNK  

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