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Re: HT uplink test via ISS?



ISS QRP test is Tuesday night local sun time (ie, WED morning) sorry for
the confusion.  I should have used UTC, but the point was that it was to
be an overnight test. We'll see ya WED morning to see how it went...

Remember, this is not really a solicitation for more people to get on the
air, but just a solicitation to try a regimented transmitting strategy as
a quantifiable test of low-duty cycle communications via ISS.  We ask that
everyone that participates in this test to focus on these aspects:

1) Put your TEST setup in your packet (so we know who is participating)
2) Set your transmit rate according to the recommended rates-vs-power
3) We need IGates capturing the data so the ARISS.NET site gets it.
   
Normally unattennded periodic beacons are NOT encouraged via ISS.  But in
this case, for this test, it is a nice way to gather data from a known
transmitting process on the uplink.  

REPORTS:  No report is necessary if your packet gets on ARISS.NET or
anyone's submitted report.  Only report if you did set up for
the test (properly) and *did-not* get seen.  This is useful data.
Your packet (or your report if unsucessful) should include power,
Xmission rate and antenna.

de WB4APR, Bob

On Tue, 15 May 2001, Bob Bruninga wrote:

> I would like to propose an ISS experiment, where we dedicate the overnight
> time of 22 May in the USA as an HT uplink test via the ISS digipeater?
> The collective objective is to test the viability of HT QRP packet uplinks
> under controlled conditions:
> 
> Test period:    Midnight local time 22 May to 8 AM on 23 May)
> Test stations:  HT's (or equivalent) on omni antennas, 5W power
> Test rate:      One packet every 1 minute
> 
> The objective is the collective throughput, not individual packets.  So if
> you set up in accordance with the test criteria you ARE A SUCCESSFUL
> PARTICIPANT.  If you got in, we got it.  If you did not, but your station
> was properly configured, then please submit a report including your sky
> view and any ideas why you might not have gotten in.  This is important
> data.
> 
> Although we are focused on QRP uplinks, we do not want anyone to feel
> excluded.  If higher power stations continue to operate, we ask that they
> operate at a reduced duty cycle equivalent to their higher power:
> 
>   5W Omni every 1 minute  <== the objective for HT's 
>  10W Omni every 2 minutes
>  25W Omni every 3 minutes
>  50W Omni every 4 minutes <== typical Kenwood Mobile APRS radio
> 100W Omni every 6 minutes
> 
> In any case, we would ask that all packets include their station's test
> conditions such as "5w omni every 1 min", or "5W beam north evy 2 min"
> or "5W omni in trees" or "1W omni on hill"
> 
> An ALOHA channel like the ISS with blind transmitters can probably support
> about 120 stations per pass.  The way to achieve this is for everyone to
> transmit LESS OFTEN so that there are fewer collisions.  Just set your rig
> to the recommended TRANSMIT RATE, go to bed, and lets see how we did in
> the morning (WED).
> 
> If we still have too many people on the uplink, we may try the test again
> later with the 5W stations at once every 2 minutes which I think is
> probably closer to the optimum rate given the number of people that will
> be trying...
> 
> Depending on the success of this test, we might then turn it around for an
> HT MESSAGE DELIVERY TEST at some later time.  In this test we will have a
> few dedicated uplink stations seeing if they can deliver messages to X
> number of HT's with STOCK RUBBER DUCKS on receive.  Think of these tests
> as emergency preparedness tests...  
> 
> If anyone knows of any problems with this proposal for 22 May, please
> speak up...  I chose that date when most of us are asleep during the
> passes over the USA...
> 
> de WB4APR@amsat.org, Bob
> 
> ISS-APRS FAQ:       http://web.usna.navy.mil/~bruninga/iss-faq.html
> PCsat Design        http://web.usna.navy.mil/~bruninga/pcsat.html
> CUBESAT Designs     http://web.usna.navy.mil/~bruninga/cubesat.html
> APRS LIVE pages     http://web.usna.navy.mil/~bruninga/aprs.html
> APRS SATELLITES     http://web.usna.navy.mil/~bruninga/astars.html

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