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Re: S-band



Tony,
Are you spinning the polarity of the dipole?  Remember that AO-51 has a 
linearly polarized S-band antenna, so you will have x-pol fades if you 
don't turn the antenna for best reception.  This is pretty much the same 
routine I do with an "Arrow" antenna with the UHF downlink....a friend 
of mine affectionately calls it the "arrow dance".

Yesterday I had good luck with W7LRD's RHCP 16-turn helix.  I brought 
one of those to the SVHFS conference last weekend and tested it on the 
range. It measured over 14dBd (linear), with about 20dB return loss at 
2401 MHz and only a couple dB max of x-pol difference. 

You might see if you can find a signal source to make sure you don't 
have a bad connection or a tempermental local oscillator.  If you don't 
have a 2401 signal source you can usually find a birdie coming out of 
your computer somewhere around 2400 MHz. 

-Andy K0SM/2


ANTHONY JAPHA wrote:

>Help!  
>I've had a lot of trouble with S band.  I'm using a K5GNA converter with
>dipole reflector and either an FT817 or HT.  I've also tried a patch
>antenna and a helix.  The results are always the same:  very strong signals
>(and a few QSOs), but usually in very short fragments.  A syllable or two
>or three and then nothing, with the signal having disappeared into the
>noise.  Doppler is not the problem in this case.  I've tried an in-line
>attenuator with no better results.
>
>What am I doing wrong?
>
>Tnx and 73,
>Tony, N2UN
>  
>




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