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Query: cone
Links: 19 | Categories: 1
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End-Fed antennas are NOT balanced systems; but neither are verticals, ground planes, discones, windoms, zepps, Marconis, half-slopers, et al. Additionally, the low-impedance antenna port of your transmitter/receiver is not balanced. -
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Conejo Valley Amateur Radio Club, article edited by Rory Eikland, KG6HCU and Ken Larson, KJ6RZ, they have had excellent experience building and using J-Pole antennas, and share their experience on planning VHF and UHF Jpole antennas. -
Programs for common antennas and some experimental, includes, dipoles, quad, Yagi, verticals, discone, jpole skyhoppers and parabolic antennas -
A DIY discone antenna project made to improve receiveing performance of an RTLSDR receiver. -
Calculate dimension for discone antennas online -
Constructing a Lindenblad antenna for 137MHz NOAA satellite reception involves specific design considerations for optimal performance. The resource details the use of 4mm galvanised steel fencing wire, 300-ohm television ribbon cable, and wood/plastic components for the antenna structure. Key dimensions for a 137.58MHz-resonant antenna are provided, derived from the ARRL Satellite Handbook, specifying s, l, w, and d as 42, 926, 893, and 654mm respectively. The antenna is designed for Right Hand Circularly Polarised (RHCP) signals, requiring the four folded dipole elements to be tilted clockwise by 30 degrees. A significant aspect covered is impedance matching between the antenna's 75-ohm impedance and a typical 50-ohm receiver input. A twelfth-wave matching transformer, constructed from 117mm sections of 50-ohm RG-58 and 75-ohm RG-59 coax with a 0.66 velocity factor, is described. The article also addresses coaxial cable and connector selection, recommending 75-ohm Type-N connectors for RG-6 cable in professional setups and F56/F59 connectors for general use, while strongly advising against PL-259/SO-259 connectors for VHF. Strategies for mitigating Radio Frequency Interference (RFI) are discussed, including antenna placement to shield from local TV transmitters and the use of commercial or DIY band-pass filters, such as cavity resonators or helical notch filters, along with ferrite chokes on coaxial cables. Antenna orientation is explored, noting the Lindenblad's 'cone of silence' directly overhead and its maximized sensitivity towards the horizon. An experimental vertical tilt of 90 degrees is presented as a method to improve overhead reception and reduce interference from strong horizontal signals, particularly relevant in high RFI environments like the Siding Spring Observatory site. -
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A discone antenna plan and pictures with renderings designe mainly for RTLSDR usage -
The basics of what is a discone antenna for wide band or bandwidth omnidirectional applications. -
About the basics of what is a discone antenna for wide band or bandwidth omnidirectional applications -
Specializing in vintage and antique speaker repair,recone and restoration. -
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Conejo Valley Amateur Radio club AA6CV CVARC is an ARRL special service club. -
Homebrewing a vhf bicone antenna with 8 clothes hangers and 4 feet of Sch40 non-metallic rigid conduit -
DTMF Remote Controls, DTMF tone generators and broadcasting products, remote broadcasting via cell phone, cell phone mixer and remote phone keypad -
A mailing list in spanish to exchange shortwave dx i nformations -
The Conejo Valley Amateur Radio Club (CVARC) is a 501(c)3 organization incorporated as a non-profit in the State of California, and established for the benefit of the amateur radio community.