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In a coax-fed dipole, the coax core is connected to one element of the dipole and the braid to the other. At the rig, the coax core is connected to the hot end of its output and the braid to the chassis, which is the common or cold end. Incidentally, the chassis is connected to shack earth which is bonded to mains safety earth. This serves 2 purposes - as ...


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Here's one you could homebrew, using a diode matrix, push button switches magnetic latch relays and SO-239s. The schematic shown is for 3 antennas but it's extendable. Freewheeling diodes for the relay coils and LED indicators are not shown. The SO-239 bodies are to be mounted on the aluminium enclosure, interconnected and earthed. Reliable operation ...


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RF-specific parts aren't really required at HF. The physical dimensions of ordinary switches and relays are so small relative to the wavelengths involved that as long as you make a reasonable attempt to keep the leads short, it will work just fine. Specific product recommendations are off topic, but there's really no need. Just be mindful of current and ...


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There are two reasons you might want to upgrade coax: lower loss other reasons "Other reasons" include durability, weather resistance, and absolute maximum ratings. Usually the coax either meets these requirements or it doesn't. If it meets these requirements then you'd only upgrade to reduce loss. You say your cable has a loss at 50 MHz of 10.5 dB per ...


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Your question leaves too many unknown variables to give a specific answer. Resonant or non-resonant antenna, feedline length, operating frequencies, power levels, your station hardware, and your budget are all important considerations. There is a wealth of information in various ARRL publications that will provide a lot of guidance. The "Antenna Book" is ...


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The loses with RG 58 for HF are fairly small unless you have a long run of coax. The losses are higher for VHF and much higher for UHF, but as most VHF/UHF is short range, often to a repeater, the loss of power usually does not have much of an impact. Personally I prefer to use LMR400 instead of RG58, as it has lower losses especially on VHF and UFH. It ...


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Your question seems as much about psychology as much as technical concerns. We mainly favor the technical questions, but I'll take a stab at the psychological aspects also. All of you, please feel free to disagree with my conclusions! Coaxial cable is fairly inexpensive for many, compared to our time, even for LMR400. (Your mileage may vary.) For many, ...


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As others have pointed out in their answers there's a distinction between RF and DC which makes this use of coax still an effective feed line for a dipole antenna. There's going to be plenty of people that consider this bad form as it is feeding a balanced antenna with an unbalanced line. Even so I checked my ARRL Antenna Book and they show a dipole being ...


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