TM-9-2350-358-BD M109A6 Battlefield Damage Assessment and Repair Download
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TM 9-2350-358-BD 13-8. ANTENNA, DAMAGED OR MISSING - CONTINUED Option 3: Suitable mast. Limitations: Can only be used on a stationary vehicle and when a tree is available for suspension of the antenna. Personnel/Time Required: • 1 soldier • 0.5 hour Materials/Tools: • Cable, telephone, WD-1/TT, 1 roll (scavenge from available source) • Insulators (e.g. , glass, plastic, leather, nylon, etc. ), five required (scavenge from available source) • Rope (item 52, Appendix C) • Sticks or branches, 4 feet length, three required (scavenge from available source) Procedural Steps: WARNING Do not touch bare wires on expedient antennas with the radio keyed. You could get burned and/or shocked. 1. Determine length of wire needed for radiating element of a one-quarter wave antenna using the following formula: Length (feet) = 234 divided by frequency (MHz) or Length (meters) = 71.37 divided by frequency (MHz) EXAMPLE: radiating element for a frequency of 50 MHz: L (feet) = 234 divided by 50 MHz = 4.68 feet or L (meters) = 71.37 divided by 50 MHz = 1.43 meters 2. Cut required length from telephone cable. 3. Cut three reflector elements approximately the same length as radiating element. 13-10