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RE: S-band fade

Thanks for raising this issue Tony.  In VE4 land we have 3 stations
experiencing this same fading in and out.  Unfortunately we are loosing V/S
mode later today and for the rest of this month so we will be unable to test
some of the ideas being offered.

3 of our local systems run Bob K5GNA's downconverter, 2 on corner reflectors
and 1 on a BBQ dish.  What they do have in common is they are all 12 VDC on
the bias tee.  We will have to try Diane's VE3DI idea of getting the voltage
up somewhere around 15 or 18 VDC.  All the K5GNA downconverters behave okay
with a 2.4Ghz signal source.  I suspect that at even 100 feet of so it is
still no where near the weak signal we get from AO-51.  We can perhaps test
the voltage idea by attenuating the power of the signal source to the point
where we can duplicate the fade terrestrially.

I also have a 13LNC72 dual IF Output downconverter from KEPS that has an
operating voltage of 11-15 VDC to compare against the K5GNA devices.  Again,
we ran out of time this week to try this comparison on AO-51.  

I'm sure hoping the power to the K5GNA is the solution.  Antenna height,
rain/snow/trees etc is not an issue.  Proximity to a WIFI LAN could be
affecting one of our systems.

Please keep the ideas coming folks.

73, Alan VE4YZ
AMSAT 35968
See us here at http://www.mts.net/~ve4wsc/satcam/main.htm


|-----Original Message-----
|From: owner-AMSAT-BB@amsat.org 
|[mailto:owner-AMSAT-BB@amsat.org] On Behalf Of ANTHONY JAPHA
|Sent: May 4, 2006 10:13 AM
|To: amsat-bb@amsat.org
|Subject: [amsat-bb] S-band
|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
|Sent via amsat-bb@amsat.org. Opinions expressed are those of 
|the author.
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