We have a former ambulance that we are converting to a mobile command unit. Has anyone used one for this purpose, and have any insight on where to mount antennas? We will be using anywhere from 6-8 antennas but can't use the top of the box due to lack of a ground plane.
Any help and pictures would be much appreciated!
mobile command antennas
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Tom in D.C.
- Posts: 3859
- Joined: Tue Sep 04, 2001 4:00 pm
- What radios do you own?: Progreso soup can with CRT
Re: mobile command antennas
If you're unable to install a sheet of aluminum (groundplane) in/on the top of the box you will be limited to using coaxial antennas which present mounting problems of a different kind, or horizontal dipoles which are the wrong polarity for most PS systems. I would vote for installing the groundplane, so go ahead and buy it, bolt it to the roof, and then paint it to match the rest of the truck. Then you can put any kind of lowband, VHF, UHF, and 900 mHz antenna up there that you want. If anyone objects to this you can patiently explain the problem to them and watch as their eyes glaze over, then hopefully they'll go away and let you get the job done. While you're doing this don't forget to bond the groundplane in several places to the metal chassis and the metal body parts of the truck.
Tom in D.C.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
In 1920, the U.S. Post Office Department ruled
that children may not be sent by parcel post.
Re: mobile command antennas
Add a ground plane. You can do that with copper foil tape or thin aluminum. I did this on a fiberglass-body KW T300 pumper/tanker - a 5/8 wave whip won't work on a 11' truck, so we ran a quarterwave and added a ground plane. No problems...