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Re: Eggbeaters

Congrats on getting the EB II built.  The EB II is designed to improve the reception at lower angles and give you a more consistant signal across the elevation plane.  However, it does this at some sacrifice of signal from overhead.  If you used a 3/4 wl antenna, like a 19" whip, you would get much more "gain" at higher elevations (above 30 degrees) but you would lose the circularity feature of this design and definitley will be deaf at lower angles.  All that said, these omnidirectional antennas are low-gain and make reception without a preamp difficult--but certainly not impossible.  I found with 15 feet of 9913 and directly connected to the rig (when I was in Russia this was my setup) I could reliably hear and work FO-29 and UO-14 above about 20 degrees elevation, but all were weak signals.  AO-51 on 70 cm is not quite as loud as UO-14 was.  
A "couple of 259's" probably are causing much more loss than the 40' of 9913.  Without a preamp at the antenna, every fraction of a dB makes a difference.  A preamp at the antenna is a good investment, as you can use it with any antenna you might build or buy in the future.  The ARR in a suitable enclosure works well, and for a little more money you can still find good used Landwehr and SSB preamps around (RadioDan.com in CA used to handle refurbished Landwehr preamps).  If you have a receiver-only setup, you could build one of the Hamtronics models or even the $20 Ramsey kit (http://www.ramseyelectronics.com/downloads/manuals/PR40.pdf).
Don't give up.  I spent about 6 months, off and on, trying to hear AO-27 on an HT, then on a ground plane, then on a hand-held dipole, and finally heard it for about 5 seconds on an EB.  I was beginning to think it was a hoax :-)  That was the first time I had ever heard a satellite on 70 cm, but I kept "improving" the setup a little at a time.  Nothing made a bigger difference than adding a preamp at the antenna.
Jerry, G/K5OE
N4NAB writes:
I have constructed, very carefully I might add, a 70cm eggbeater II, got
the swr down to 1.1/1 at 435-438 .Stone deaf at 25' height and 40 foot
run of 9913. 
I must have too much attenuation in the line into the shack. I don't
have any N connectors on hand so there are a couple of 259's in the

Am I wasting my time and $$ or will a mast preamp help?

73,  John 
N4NAB/ FM14lq
AMSAT # 32411
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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