[600MRG] Dual Band Loop for 630M and 160M

[David Riley]

OK, long story, short..
 4ea. 10ft. 3/4"  copper pipes, 4ea, 90deg angles all soldered into a 10 foot square. No breaks.Add one #75 mix toroid. ( before soldering 😎 )Hoist to a tree limb by one corner.Bottom corner is 2 feet above earth, no DC connectionsLocal ground rod sees LPF and LNA commonsToroid has three turns running in to a series choke thence to a low pass filter.Output of LPF to LNAOutput of LNA goes to another 75 mix toroid with a multi turns of coax RG6 feed to shack. Great read from W8MI, learned about coax being a three wire device and common mode.
 Untuned loop provides lots of different band sigs. 
 Not much E noise with this shorted loop but lower amplitude sigs and wider bandwidth.Now searching for lowest noise figure LNA with LOTS of gain.  ?? Positioned loop where direction of preferred signals are 90 degrees away from the major noise source. Twisted wire feed sees a series .0025 cap which yields about 40R and little reactance @ 630m with 22db of return loss,and 150R with little reactance @ 160m Coax to shack sees more decoupling, LNA, splitter to 630 and 160m receivers. W1FRV sees 630m and W1NMF sees 160m WSPR sigs.. Still tinkering after all these years, 73s de Dave/AA1A 
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