Daily variability of HF propagation is caused in large part by solar energetic particle radiation carried by the solar wind, especially during the four years closest to solar minimum when x-ray and p
As s olar cycle 25 is slowly gains strength, there are now two new cycle 25 sunspots on the visible disk, regions 2767 and 2768. Region 2768 rotated over the northeast limb onto the visible disk earl
Hi Ron, -- Original Message -- Hi Ron, A simple installation should be adequate if you're not planning in-band receiving capability while you're transmitting. Otherwise more extreme measures may be n
Hi Ron, 700-1200 foot spacing should provide good in-band receiving capability. SDR receivers won't work for in-band receive, you must use a traditional transceiver such as the K3, K4HD, FTdx5000, IC
Hi Dick, If you're lucky enough to be able to install a receiving antenna about 1000 feet from your transmitting antenna, a separate high dynamic range receiver or transceiver will be able to hear we
Hi Rick, A "magnetic" loop will provide at least a 20 dB null, that's good. But it doesn't provide the weak signal receiving capability of a high performance receiving antenna. Very small magnetic lo
Hi Jim, Congratulations on your ARRL Technical Service Award Well done and well deserved! www.arrl.org/news/arrl-technical-service-award-conferred 73 Frank W3LPL _________________ Searchable Archives
Many years ago I was involved -- peripherally -- with very large phased arrays of Beverage antennas installed over very poorly conducting soil (almost solid rock) in which ground rods were completely
Hi Rick, I'm not aware that any details of this phased array Beverage design were ever published. M ost likely it was documented only in internal government engineering reports. These very large phas
Hi Bill, The antenna feed point is where common mode signals on the outside of coaxial cable shield most easily and severely degrade antenna directivity. This a critical antenna performance issue for
Hi Mark, It can be very challenging to reduce common mode adequately to preserve the directivity of low signal level antennas such as the YCCC 9 circle. My preferred approach is to bury all cables in
Leif Svalgaard of the W.W. Hansen Experimental Physics Laboratory at Stanford University -- a highly regarded solar physicist -- predicts solar cycle 25 SSN of 128 +/- 10. According to Svalgaard: "Th
Hi Lee, Your testing will be inconclusive unless you inject water into your connectors, or you could just move to Maryland where we get at least 45 inches of annual rainfall and it gets into everythi
Recently I presented "The History of Trans-Atlantic Radio Communications" to the Redwood Empire DX Association. Among other things, my presentation discusses the 1921 trans-atlantic test which was cl
Hi Kenny, A single 580 foot Beverage is an excellent 160, 80 and 40 meter antenna. I still have three of them (NE. S. W) even though I also have 8-circle arrays for 160, 80 and 40 meters. I've never
Hi Dave, 270 foot spacing is a good choice only if you're trying to eliminate QRN from local RFI sources not propagating via the ionosphere. Otherwise 350 foot spacing is optimum for suppressing QRM/
Hi Bob, While bonding the radials is desirable, its not essential. But you must NOT cross the radials over each other. The radials of a multi-element vertical array are usually bonded to a common wir
Hi Carl, If the insulation breaks down they will arc, potentially causing a fire 73 Frank W3LPL -- Dave Manuals@ArtekManuals.com www.ArtekManuals.com -- This email has been checked for viruses by Ava
Hello Henk, Most of the kinetic energy released from solar wind into the Earth's magnetosphere and then its ionosphere is in contained in the velocity of the solar wind. Much less energy is in the ex
Always beware of any communication that begins "with all due respect" -- Original Message -- With all due respect, I must ask, how many megawatts are you guys running? Wes N7WS _________________ Sear