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Re: AO-40



Hasan,

Put it up. You are getting roughly the same sun noise indications as I am 
on my 39 inch dish. As long as you can hear the increase in FT-847 noise 
floor when you power up the UEK-3000, go for it.  The pointing seems rather 
critical at times. And make sure you have the latest AO-40 Ranging Keps as 
the others were off.

Jerry, W6IHG

At 08:50 AM 7/16/01 -0500, hasan schiers wrote:
>I'm trying to evaluate my system with severe limitations, and could use some
>help.
>
>Antenna: HyperLink Tech 39" bbq style dish with dipole feed. (8 deg 3 dB
>beamwidth)
>DownConv: SSB UEK-3000 fed directly into the antenna pigtail of about a foot
>135' RG8/X to radio
>Radio: FT-847
>
>Ground testing, no way to be sure of pointing at anything but the sun.
>
>Results:
>
>Sun Noise: exactly as reported below: "a little under 1 s-unit of noise or
>about 2 segments of the s-meter lit, sometimes flickering".
>
>This seemed to indicate to me that I'm hearing pretty well...is that true
>from what I'm experiencing, or is it just wishful thinking on my part?
>
>Next:
>
>The by guess and by golly pointing I'm doing is not working out well at all.
>I hear the bird very strong with severe doppler at perigee, of course.
>However, I never got signals worth a darn the last two times this weekend
>when I checked, with squints of 8 deg. Very discouraging.
>
>My question:
>
>Am I hearing enough sun noise to indicate that my system is working ok, and
>my problem is that I'm never really pointed at the bird? I want to make sure
>everything is "jake" before going up on top of the tower. My only "reliable"
>signal source is the sun. Am I hearing enough sun noise to put the system on
>my tower? On the tower I will have full az/el control that can be peaked for
>accuracy.
>
>On the ground testing, I have no idea of my pointing other than VERY roughly
>and I have to run back and forth to the shack, adjusting azimuth crudely and
>probably a little better accuracy with elevation, by placing an inclinometer
>on the bar that supports the dipole feed and then removing it when I try to
>hear the bird.
>
>I can accurately position the dish at the sun by centering the shadow of the
>dipole equally about the point where the dipole feed support bar enters the
>back of the dish. I just can't get any confidence that I'm pointing at the
>bird...and if I am...my system isn't working worth a darn.
>
>Any and all comments are appreciated as I won't have people that can
>repeatedly go up and down that tower once we make the move.
>
>I'm beginning to experience all sorts of paranoid ideations ...mostly
>centered around the dish, which I believe should work quite well...spec'd at
>24 dB gain and worked wonderfully as a wireless internet antenna...no active
>components in it...just 39 inches wide with a dipole feed and LMR-400 one
>foot pigtail terminating in a female N connector. I'm not shooting through
>any leafy vegetation or trees when I'm evaluating the performance.
>
>HELP PLEASE!
>
>If it's the antenna, what recommendations would you have?
>
>73,
>
>hasan, N0AN
>schiers@netins.net

------------------------------------------
Dr. Jerry R. Pixton, PIXOS Designs LLC
http://www.pixos.com/designs/
jpixton@shentel.net
------------------------------------------

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