Yaesu FT-891 Operating Manual

Also see for FT-891: Information for Customers Operating Operating manual Advance manual Reference book Quick manual

8InstallationFT-891 Operating ManualBase Station Earth GroundingTypically, the ground connection consists of one or more copper-clad steel rods, driveninto the ground. If multiple ground rods are used, they should be configured in a “V”configuration, and bonded together at the apex of the “V” which is nearest the stationlocation. Use a heavy, braided cable (such as the discarded shield from type RG-213coaxial cable) and strong cable clamps to secure the braided cables to the ground rods.Be sure to weather-proof the connections to ensure many years of reliable service. Usethe same type of heavy,braided cable for the connections to the station ground bus (de-scribed below).Do not use gas line pipes in an attempt to provide a ground connection! To do so createsa serious risk of explosion!!Inside the station, a common ground bus consisting of a copper pipe of at least 1” (25mm) diameter should be used. An alternative station ground bus may consist of a widecopperplate (single-sided circuit board material is ideal) secured to the bottom of the op-erating desk. Grounding connections from individual devices such as transceivers, powersupplies,and data communications devices should be made directly to the ground bususing a heavy,braided cable.Do not make ground connections from one electrical device to another, and thence to theground bus. This so-called “Daisy Chain” grounding technique may nullify any attempt ateffective radio frequency grounding. See the drawings below for examples of proper andimproper ground connections.Improper Ground ConnectionTransceiver“Daisy Chain”GNDGND GNDLinearAmplifierPowerSupplyProper Ground ConnectionTransceiverGNDGND GNDLinearAmplifier PowerSupply