Doublet-Isolators for 300 Ohm Twin Lead

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The shown Isolators are perfect for constructing an incredible Multiband Shortwave Antenna. To assemble them, use M3x10mm cylinder head slotted Screws (x10) along with M3 hexagonal Nuts (x10). For added protection against moisture, apply a sealing adhesive to the Isolators. An SO-239 socket is also necessary for this project. Shorten the center pin to 1mm and connect it to the Twin Lead, which should be soldered in place using pre-prepared points made with a saw and file. To ensure proper centering, drill 3mm holes at each end of the Twin Lead. If the guide pin breaks during assembly, the tensile strength of the Twin Lead will still guarantee its stability due to clamping. The Antenna Wire (Dipole) used should have an outer diameter ranging from 2mm to 3mm, including isolation. A cheap Antenna Wire for the setup as Inverted Vee can be ordered on eBay. For high-quality wires and other supplies, visit the Webshop of DX-Wire. The Twin Lead (300 Ohm, Velocity-factor 0.82) used in this project can also be sourced from http://www.dx-wire.de/lng/en/kabeldraehtelitzen/300-ohm-bandleitung/300-ohm-twin-lead.html?type=N&language=en. For the Doublet and Leads, proven lengths correspond to the ZS6BKW or G5RV Antenna model. For example: * G5RV 6-Band (including 160m): 2x 30.94m (Dipole) and 17.20m Twin Lead * G5RV 5-Band (including 80m): 2x 15.47m (Dipole) and 8.60m Twin Lead * G5RV 4-Band (including 40m): 2x 7.74m (Dipole) and 4.30m Twin Lead When assembling the EndIsolators, please remember to cut each leg of the Dipole approximately 4 cm longer. The Endisolators can be attached with narrow Cable Ties at the bent ends. A Balun for undefined Impedances is not required for portable operation but is generally recommended. A Ferrit for max.100 Watt can be obtained from http://www.dx-wire.de/lng/en/ferriteringkerne/ringkerne-zur-funkentstoerung/t36/23/15-3s4.html?type=N&language=en. The Balun consists of 13 turns of Twins, preferably PTFE (http://www.dx-wire.de/lng/en/kabeldraehtelitzen/ptfe-teflon-litzen-und-draehte/ptfe-teflon-wire-twisted-2-x-075mm2.html?type=N&language=en). It should be connected between the Antenna and Transceiver (or external Tuner). An Antenna Tuner is necessary for all-band operation. In most cases, the built-in Tuner in the Transceiver will suffice. For more details, search for G5RV on the Internet. 73 es 55 de DH1ND