Hi again, everyone.
It's a little overwhelming to get so much help at once, but thank you, everyone, for all of it.
One clarification: I did indeed mean pF, not uF for the capacitors in the matching circuit.
Also, we performed another ridge test this evening (another typo there: the ridge is 3.18km from the roof where we have the ground station setup), using the complete ground station (minus pre-amp), and TH-D7 with rubber duck.
We transmitted from the ground station, while varying the amount of attenuators between the TS-2000 and coax to the antenna. The "PWR" column is in the format (TH-D7)/(TS-2000). With each test, two 319-byte packets were sent by the ground station in rapid succession. The results are below. If any of this is not clear, I will do my best to clarify things.
Also, the entire test was performed at 437.405MHz, at 1200 baud, even though we would like to operate at 9600. I have gotten 9600 baud to work when two TH-D7's are across the room from each other, but since 9600 baud didn't work during the initial configuration, we decided to just characterize the rubber duck at 1200.
Ant. Pos. PWR Atten. Packets Vertical .05W/5W 0dB 2/2 Vertical .5W/5W 50dB 0/2 Vertical .5W/5W 45dB 1/2 Vertical .5W/5W 45dB 2/2 Vertical .5W/5W 50dB 0/2
Horizontal .5/5 50dB 0/2 Horizontal .5/5 45dB 1/2 Horizontal .5/5 45dB 0/2 Horizontal .5/5 45dB 0/2 Horizontal .5/5 45dB 0/2 Horizontal .5/5 40dB 0/2 Horizontal .5/5 40dB 0/2 Horizontal .5/5 35dB 0/2 Horizontal .5/5 30dB 2/2 Horizontal .5/5 30dB 1/2 Horizontal .5/5 30dB 2/2
45 deg. .5/5 30dB 2/2 45 deg. .5/5 30dB 2/2 45 deg. .5/5 35dB 2/2 45 deg. .5/5 40dB 2/2 45 deg. .5/5 45dB 1/2 45 deg. .5/5 45dB 0/2
Comments? Concerns? Questions?
My initial interpretation of these data is that our square loop antenna has a MUCH lower gain than is required, and something like a short length of measuring tape would be a better substitute, as has been suggested by numerous people.
-Nate
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Nathaniel S. Parsons