text: Chapter 6
  • Allow radios to warm up for several minutes before use. Since extreme cold lowers the voltage
  output of a dry battery, try warming the battery before operating the radio set. This minimizes
  frequency drift. Flakes or pellets of highly electrically charged snow have been reported in
  northern regions. When these particles strike the antenna, the resulting electrical discharge
  causes a high-pitched static roar that can blanket all frequencies. To prevent this, cover all
  antenna elements with polystyrene tape and shellac.
  6-141. Protect radios from blowing snow. Snow can freeze to dials and knobs and blow into the wiring,
  causing shorts and grounds. Handle cords and cables carefully because they lose their flexibility in extreme
  cold. Properly winterize all radio equipment and power units. Check the appropriate technical manuals
  (TM) for winterization procedures.
  Power Units
  6-142. As temperature decrease, operating and maintaining generators becomes increasingly difficult.
  Protect them from weather as much as possible.
  Batteries
  6-143. The effect of cold weather on wet and dry cell batteries depends on the type and kind of battery,
  the load on the battery, the use of the battery, and the degree of exposure to cold temperatures.
  Shock Damage
  6-144. In extreme cold, most synthetic shock mounts get brittle and fail to cushion the equipment. The
  jolting of a vehicle during movement can damage radios. Check the shock mounts often, and change them
  when needed.
  Microphones
  6-145. Moisture from a Soldiers breath can freeze on the perforated cover plate on the microphone. Use
  standard microphone covers to prevent this. If no standard covers are available, improvise one from rubber
  or cellophane membranes or from rayon or nylon cloth.
  Breathing and Sweating
  6-146. A radio generates heat when it is operated. When it is turned off, the air inside cools and
  contracts, drawing cold air in. This "breathing" can bring still-hot parts into contact with subzero air. This
  can cool the glass, plastic, and ceramic parts too quickly, and cause them to break. If the cold equipment is
  brought suddenly into contact with warm air, moisture will condense on its parts. This is called sweating.
  Before cold equipment is brought into a heated area, wrap it in a blanket or parka to ensure that it will
  warm gradually to reduce sweating. Thoroughly dry all equipment before taking it back out into the cold.
  Otherwise, moisture caused by sweating will freeze equipment.
  MOUNTAIN OPERATIONS
  6-147. Operation in mountainous areas presents many of the same problems as operation in northern or
  cold weather areas. It also makes selecting transmission sites a critical task. Terrain restrictions often make
  relay stations necessary for good communications. Terrain obstacles often make line-of-sight transmission
  necessary. Also, the dirt in mountainous areas seldom conducts electricity well. Use a complete antenna
  system such as a dipole or ground-plane antenna with a counterpoise. Maintenance requirements in
  mountainous areas resemble those in northern or cold weather areas. Tricky mountain climates require
  flexible maintenance planning.