Preliminary conclusions:
Lack of line-of-sight caused VHF to be unusable at the 28 mile distance, especially with the ridge line between Jeff AE5ME and Scott KC5SHE, which is approximately 20 feet taller than either antenna. Attenuation on the order of 100 db is probably occurring. Situation did not change whether station was running 0.5 watts, 5 watts, or 75 watts. Guessing that usable distance will probably be on the order of 5-10 miles tops at 20 foot antenna elevations. This is common on 2m simplex, so it confirms what we originally believed.
Normally that would lead us to say we need ball tall antennas on high sites. However.....
The real magic occurred on ground wave on both 30m and 40m. It one word it was excellent. 30m was a more quiet band, but also a very narrow band to operate within. Easily can obtain good copy of the signal out to 28 miles. The 1.75 mile signal was essentially "full quieting". Ridgeline essentially had very little impact on the signal strength. Similar results on 40m, but also a lot more noisy from other sources, such as DX and shortwave radio stations adjacent to the band.
Between 30m and 40m, I think we are finding a band with decent propagation characteristics, that will keep us from having to use the traditional 250 foot or above tower to build a digital network. That has been the traditional issue that kept traditional 2m packet from being continuous coverage.
All tests were conducted with some version of PSK, whether it be 125, 250, or 500. Did some -1000 in short bursts, as well.
Further investigation with Scott KC5SHE next weekend will help establish values for comparison to the closer range transmissions. Probably looking at doing something Sunday evening, October 5th.
Jeff, I'm excited about using FLDIGI to break through the old stereotype that you need large power supplies, radios or complicated antennas to do something useful on the "shortwave" frequencies.
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