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AMSAT Experiment Volunteer needed



AMSAT guys:

We need a volunteer to help us get 4 small AMSATS
working and launched in the next 3 months.  I'm totally
overloaded.  Here is what we need:

When PCSAT2 and ANDE and RAFT amateur satellites
are all deployed on and from ISS, (along with ARISS already 
running two radios too) we have a frequency interference 
issue to work on.

Here is the test we need:

Set up a kenwood D700 (the radio on ISS) listening to a 
distant (not full quieting) repeater on  a convenient antenna.  
Now set up a signal generator on another antenna about 
100 feet away.

(If you dont have a D700, do it on any comparable RiceBox)
(in fact, do it on every radio you have to get more data)

While the repeater is in use, dial in different frequenceis and
power levels on the sign gen to find out at what level on the
sig-gen causes the Kenwood D700 receiver to be blocked.

Do this for kenwood on 145.800 and sig gen on 145.825
(only a 25 KHz offset).  Also do it for say 100KHz and 600KHz
just for general usefullness too.

Do it also on the UHF band.  Also, adjacent channel, 500 KHz
1 MHz and 1.5 MHz offsets.

Use the usual "lab" or "scientific" method to record your
setup and results and write-it-up so that there is no
ambiguity.  It should stand-alone as a technical reference
paper.   We dont want "opinions" we want measurable
and reproducible measurements.

Also try a few different transcievers just so we can see
the "trend".

Of course you can do all this on the bench with 2 sig gens
if you have it all.

So here is someone's chance to volunteer and do someting
to help get the next 3 AMSATS working on orbit and on ISS.
If  the above general concept of the test is not clear, then 
dont volunteer,  I need  someone to just take the ball and run
with it.   

Go study the problem of typical blocking levels which will 
impact us when we start having multiple ham radios on ISS.  
This will also be very useful information for general HAM use 
also when setting up EOC's and other comms events where 
more than one radio is being operated.  We all have reasonable 
"feels" for what we can get away with, but we need something 
written down and measureable ... that can be a reference.
Maybe this test has already been documented.  If so, find it
for us.

Yes it is easy to do.  But just takes time (which I dont have)

thanks.
Bob, WB4APR
PCsat,PCSAT2,ANDE,RAFT,ARISS,MARScom
(all due by May!)
----
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