Interesting results. Erik was primarily using the Barstow tower antenna at 350 ft above ground but it's on the NNE face of the tower. I was listening on the other antenna which is 250 ft above ground but on the SSE face of the tower. Could not hear AB3LE or KB3RAN on either antenna. Both antennas are Diamond X300NA's with a 6.5db gain (not sure if that's in dbi or dbd).
Unfortunately, the south county is low and blocked by rapidly rising terrain to the north. My guess is that tower shading was the reason for no copy on the 350ft NNE antenna and low antenna height is the reason for no copy on the 250 ft antenna.
If it makes it through the reflector, below is the terrain profile between the 350 ft antenna at Barstow and AB3LE, assuming his antenna is about 15 ft off the ground. Note the terrain "hole" down south on the right side of the picture. The link calculation implies we should be able to hear AB3LE with a decent margin but the calculations don't account for the effects of tower shading. This is why we need to link the CARA 2M and 440 repeaters for full county coverage.
This plot was generated from VE2DBE's on-line calculator at https://www.ve2dbe.com/rmonline_s.asp The brown is the dirt. Green is trees. Red is an obstruction like a building or other tower.
The 440 repeater in Lusby is on the tower face towards Ranch Club and Drum Point, and is high enough and close enough to have line of sight to most of Ranch Club and Drum Point. This is why we need to link the CARA 2M and 440 repeaters for full county coverage.
NEXT WEEK'S TALK-AROUND TUESDAY IS ON 10M (28.355 +/-)
Tried to get in but I don't think you heard me. I'll try again next Tuesday.
Dave
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