Friday, December 20, 2013

VHF wire antenna for field use

As a VHF antenna for field use, you can use the wire antenna for the range of 144-146 MHz. This antenna wire has a sufficiently large size of its length 16 meters 8L is the wavelength. A feature of this wire antenna designed as a radio amateur from Germany is that it is made on insulating cord. All elements of VHF antenna made ​​of wire with a diameter of 3 mm. Part of Directors of the wire are the same size equal to 915 mm (antenna DJ4OB in the figure below). The vibrator is made of a wire or tubing of different diameters, the material from which the tubes are made to be the same. The upper antenna element DJ4OB vibrator has a diameter of 8 mm and a bottom diameter of 2 mm. Input impedance of wire antennas for VHF band 144-146 MHz is about 240 ohms. The antenna gain of about 15 dB. Since the antenna is a rigid base (yoke), it can easily be rolled up and thereby transported to the place of deployment. This wire antenna can operate only in one direction for obvious reasons.
VHF wire antenna dj4ob for field use

No comments:

Post a Comment