Tuning across the AM BCB with both radios. The K3S had the 6 khz roofing filter installed. To get it wider you would need to buy the 11 khz filter. The KC-7300 is using a Heath HS-1661 speaker. K3S is using the Elecraft SP3 speaker. ... https://www.youtube.com/watch?v=US-sQ1MB2ZE

Please see updated info https://www.youtube.com/watch?v=oFOM2Y45zQA After 3 weeks of experimentation and using EZNEC, here is what I consider to be the ultimate configuration for the EFHW 80-10. This provides the minimum amount of high angle radiation and maximum low angle radiation over the HF spectrum. I was more concerned with radiation pattern than SWR. The best SWRs was found with a straight wire, up high and fed on the high end however it was too directional and had high angle lobes off the back. The worst configuration was the inverted Vee which waste huge amounts of power shooting straight up! I did not find a need for any line chokes. The coax is LMR-600 and it lays on the ground for 100 feet. This takes care of any "shack RFI" problems. This antenna now begins at 6 feet above ground, where the black box is, goes vertical for about 50 feet then slopes gently to about 35 feet. Would an extensive ground radial system help? Maybe on 80 meters but the radials would need to be a half wavelength, 130 feet each to really do much. I doubt if the upper bands would benefit but I might try a few just to see what happens. The ground rod is just for lightning protection, not RF. So after many years I now have an all band antenna that performs as well and in many cases better than my doublet plus I no longer need to resonate the system with a tuner. Just a little "touch-up" on a few bands with the auto tuner is sufficient. UPDATE 5/16/2016 After multiple attempts to run high power in cw mode I now recommend keeping your power below 150 watts otherwise the transformer will overheat and cause your SWR to increase. The ICAS power rating of 1KW is misleading and the definition of that term is ambiguous. ... https://www.youtube.com/watch?v=QLwwzUXN3rU