Well said, Greg -- to clarify my original comments:
1. Arboreal QSB is real, but... 2. It's not that significant. 3. Switching polarity helps quite a bit.
I really only notice it when operating FO-29 on passes during the height of the Spring when the leaves seem to have the most moisture.
Otherwise, it's not a general concern. But it is fun to say "Arboreal QSB".
-- bag
Bryan KL7CN/W6 Location: CM98, usually E-Mail: bryan@KL7CN.net Telephone/SMS: 408-836-7279
On Sep 14, 2018, at 14:13, Greg D ko6th.greg@gmail.com wrote:
Hi Bob,
Trees probably do have an effect, but unlike others, I've not found it to be a significant problem. At least, not one where I need to plan my passes around which trees might be in the way. The only time they did was with AO-40, where transmitting on 70cm directly into a huge oak tree would have the signal bounce back and interfere with the 2.4 ghz downlink. One could map out where the limbs were based on the results.
In an area of the country where shade in the summer is prized more than many other things, taking a chain saw to a heritage-sized oak tree in pursuit of a QSO just wasn't an option. So, AO-40 contacts to the south-east never happened. Then "unintended chemistry experiments in space" made it no longer relevant. {sniff} The only issue I have with the trees now is to keep them trimmed appropriately so they don't snag the antennas as they swing round.
Greg KO6TH
Bob- W7LRD wrote:
Hi All- Just wondering-in the real world how much attenuation is there with trees? I am surrounded with fir trees, a huge maple tree and cedar tree, (I live in the north west). I run a IC-910, preamps at the cp yagis.
73 Bob W7LRD
Seattle _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb