TO: ALL WOOD COUNTY EMERGENCY COMMUNICATIONS AMATEURS
ALL NON-WOOD COUNTY EMERGENCY COMMUNICATIONS AMATEURS
FROM: KEN HARRIS WA8LLM
WOOD COUNTY EMERGENCY COMMUNICATIONS INCORPORATED
WOOD COUNTY BULLETIN NR 13.46 DATE: November 17, 2013 SUBJECT: TEMPORARY/EMERGENCY HF ANTENNA
A multiple band, center feed, High Frequency, or HF Antenna can be built, and used, as an Emergency or Temporary antenna using almost nothing more then lamp cord, Anderson Power Pole connectors, and pieces of Plexiglas. The lamp cord which comes molded together can be stripped into two conductors, and then cut into different lengths for the various HF frequencies. Anderson Power Pole connectors are used to separate the conductors for the different bands.
The Plexiglas pieces have two purposes, one to restrain the connectors from pulling apart, and to be used as an insulator when separating the antenna into different bands. The Anderson Power Pole connectors are placed on the ends of the lengths of conductors after they are placed through holes on each end of the Plexiglas.
The coax feed point can be made with a copper pipe "T" fitting, a short piece of plastic pipe, two copper pipe caps, and a SO-239 coax connector. Since the antenna is going to be used as a Temporary or Emergency antenna, making it a balanced antenna is not required.
The antenna can be placed with the center and both ends at the same height to form as a Dipole, or with the ends close to the ground as an Inverted "V" antenna. The center of the antenna has been used with the center no more 16 feet high and works just fine.
Here are the lengths of conductors, if the antenna is made for the original five bands of 80, 75, 40, 20, 15, and 10 Meters. Starting from the center feed, going each direction the lengths of the conductors are 7'6", 2'11", 5'6", 15'3", 26'3", and 4'0". The pieces of Plexiglas between the lengths of conductors are 1/4 inch thick, cut to one inch wide and three inches long. A hole about the size of the wire conductors is placed on each end about 1/2 inches from the ends.
With a little ingenuity the lengths of the conductors can be removed from the center feed for storage. Also a shield over the SO-239 can be used to keep water from getting to the coax connector and feed line.
Ken Harris WA8LLM
WCEC
Wood County WV