10 Microwatt tests...

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AA1A
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Joined: 2009/01/26 - 22:37
10 Microwatt tests...

Thanks to all of the stations who copied AA1A WSPR on 30M down to a power output of 10 microwatts. It was a good exercise to see what can be done under quiet and normal conditions 24/7. The antenna used was a loop made from Monster Dog wire meant for direct burial which exhibits very high voltage insulative quality and low insulation dielectric constant ( ethylene ), available from E-Bay. It makes great high power twin lead as well. It was simply thrown up over the trees and fed directly from a balun and tuner.
The transmitter was an Icom IC-718 set to a power out of 1 watt and then sent through a coaxial attenuator ( -20db @ 50W rating Weinchel ) and then through a HP calibrated step attenuator ( to -50db total ) to 10 microwatts or -20dbm.
Measurements ( S21 ) made of the entire attenuator network on an Agilent VNA indicate that power output was 9.3 microwatts.
One noted anomaly was that during any time of damp or wet weather, the propagation disappeared ( because of the loop in wet trees ) when nothing was copied cross country. This seems to be the power or noise floor as recorded below.
The best DX was with W3HH @ 1104 miles @ 10 uW for 110.4 million miles per watt.
The near field was usually good copy out to over a mile.

2009-11-29 16:18 AA1A 10.140138 -22 0 FN42pb +0 0.001 KB3VR FM19la 633 393
2009-11-29 16:16 AA1A 10.140138 -25 0 FN42pb +0 0.001 KB3VR FM19la 633 393
2009-11-29 16:14 AA1A 10.140138 -23 0 FN42pb +0 0.001 KB3VR FM19la 633 393
2009-11-29 12:52 AA1A 10.140130 -27 0 FN42pb +0 0.001 W9HLY EN70mt 1195 743
2009-11-29 12:48 AA1A 10.140130 -26 0 FN42pb +0 0.001 W9HLY EN70mt 1195 743
2009-11-28 18:56 AA1A 10.140150 -26 0 FN42pb +0 0.001 K4RKQ FM08sd 790 491
2009-11-28 18:42 AA1A 10.140152 -26 0 FN42pb +0 0.001 K4RKQ FM08sd 790 491
2009-11-28 16:30 AA1A 10.140133 -29 0 FN42pb +0 0.001 W3CSW FM19kd 631 392
2009-11-28 16:28 AA1A 10.140133 -27 0 FN42pb +0 0.001 W3CSW FM19kd 631 392
2009-11-27 16:22 AA1A 10.140133 -25 0 FN42pb +0 0.001 W3CSW FM19kd 631 392
2009-11-26 18:20 AA1A 10.140144 -27 0 FN42pb +0 0.001 KG4ZUO EN90ql 847 526
2009-11-26 18:06 AA1A 10.140137 -24 1 FN42pb +0 0.001 KG4ZUO EN90ql 847 526
2009-11-26 16:34 AA1A 10.140132 -32 0 FN42pb +0 0.001 W3CSW FM19kd 631 392

11-24 and 11-25 Missing from data base

2009-11-23 16:52 AA1A 10.140144 -25 0 FN42pb +0 0.001 KB3VR FM19la 633 393
2009-11-23 16:42 AA1A 10.140145 -25 0 FN42pb +0 0.001 KB3VR FM19la 633 393
2009-11-23 12:14 AA1A 10.140140 -29 0 FN42pb +0 0.001 W9HLY EN70 1209 751
2009-11-23 12:10 AA1A 10.140140 -25 0 FN42pb +0 0.001 W9HLY EN70 1209 751
2009-11-19 19:56 AA1A 10.140132 -27 0 FN42pb +0 0.001 W3CSW FM19kd 631 392
2009-11-19 19:50 AA1A 10.140132 -32 0 FN42pb +0 0.001 W3CSW FM19kd 631 392
2009-11-19 12:00 AA1A 10.140130 -27 0 FN42pb +0 0.001 WC9C EM69hh 1436 892
2009-11-19 09:48 AA1A 10.140131 -29 0 FN42pb +0 0.001 WC9C EM69hh 1436 892
2009-11-18 09:26 AA1A 10.140129 -30 0 FN42pb +0 0.001 W3HH EL89vb 1777 1104
2009-11-18 09:04 AA1A 10.140129 -29 0 FN42pb +0 0.001 W3HH EL89vb 1777 1104
2009-11-18 04:44 AA1A 10.140128 -29 0 FN42pb +0 0.001 W3HH EL89vb 1777 1104

TNX from Dave @ AA1A - WD2XSH/17