I wonder if we could collect data from skilled portable "arrow" operators on the reception of ISS comms near the horizon during upcoming school contacts.
The interesting question is the viability of using well placed fixed tripod "arrow class" antennas at AOS and LOS instead of the current requirement for a full AZ/EL Oscar class antenna system at the school. By using two fixed portable beams on the AOS and LOS sides of the school for reception, for example, then maybe the 50W uplink can work fine from a more simply located and operated central omni antenna that is easier to set up.
A concept paper with details on this idea will be posted Monday afternoon at http://aprs.org/aos-los-test.html
The desired data would be a minute-by-minute log throughout the pass of ISS signal quality especially noting any nulls or fades without moving or adjusting the antenna. Just orient the beam vertically with an up tilt of 15 degrees. Then aim it in Azimuth half way between AOS (LOS) and when it rises above (drops below) 30 degrees elevation to cover the first (or last) portions of the pass. Above 30 degrees the ISS is 3 times closer and 10 dB stronger and would probably be heard fine on the central omni.
An audio recording would make it easier to prepare the log after the pass or you can just make checks or X's every 5 seconds on a piece of paper and summarize it later. Do NOT run open squelch. Set the squelch for normal ham radio operation to silence the radio when the signal would be unintelligible anyway, since we would not want unintelligible noise from one receiver to distract from good audio from the possible others..
The concept is to bring in all three receiver speakers (left-to-right) into the auditorium operating position to give equal weight to each receiver but also give a sense of the passage of the ISS. During this test, It is tempting to want to re-orient or move your AOS (or LOS) beam, but we need the data horizon to horizon on the original fixed antenna orientation to see how well the squelch eliminates the distraction of a noisy receiver when it is not the prime contributor.
If this test shows any promise, it could not only eliminate all the complexities of long crossed yagis, AZ/EL rotators, big masts and active tracking, but also completely eliminate the problem of long runs of coax from the school gymnasium to the antennas. The coax is eliminated by placing 50W mobile rigs (capable of cross band repeat) at each of the possible three antennas and operating them remotely via 3 UHF HT's indoors on-stage (coupled into the sound system).
So, if there will be an ISS school contact within range of your station, and you have an arrow on a tripod at your QTH, you could collect data to see if this idea is a possibility. Again, this is *independent* of the actual school contact, you are just taking your own receive data where ever you are of how well an arrow on a tripod can hear the ISS at low elevations. Be sure to find a place with a good horizon at AOS(or LOS) to set your antenna.
I'm on deadline to deliver a satellite in 12 days, and so if someone else might be interested in collecting and summarizing any incoming reports, that would be helpful too.
If we learn that there will be any significant fades or loss of signal, then this idea fails... But if it works, then the two arrows, tripods, three mobile rigs and three UHF HT's could be made into a suitcase GOKIT to standardize school contacts with a lot less work.
Just an idea Bob, WB4APR