Fire Dispatch Training – Part II April 10, 2009

We’re having two training workshops to focus on the FDOC dispatch area and field stations for the upcomming dispatch drill. Please attend one of these workshops. We’ll be meeting at the FDOC located in the basement and gathering in the parking area. 18311 Gothard Street, Huntington Beach, CA  92648. Please use caution driving on the property. Use the KH6FL/Repeater (City Hall Machine) for assistance arriving and parking.

Homebrew suction cup antenna mount

When using the suction cup mount on fiberglass or other non-metallic surfaces you may find that your antenna will work significantly better if you provide a ground plane or counterpoise for the antenna to work with. Without a ground plane, most mag mount antennas perform poorly and exhibit a high VSWR. Two solutions to this problem are shown in the attach photos. In the first photo, 3 brass rods are shown spread out perpendicular to the antennas whip forming the ground plane; in the second photo, 4 orange stranded wires are shown. When using stranded wires, a small amount of tape is used to hold the wires in position on the fiberglass roof forming the ground plane.  The length of the rods or wire radials should be approximately 10% longer than a ¼ wavelength at the operating frequency. For 2 meters a ¼ wavelength is 19 inches, so the radial should be about 21 inches. The radial length is not critical something in the ballpark of 21 inches will in most cases work fine for a temporary antenna setup. We’ll be discussing these technical issues as well as other fundamentals of FDOC operations and Field Station operation.
Radials on scution cup antenna mount

Leave a Reply

You must be logged in to post a comment.