Tuned half-wave dipoles have been among the most important antennas from the beginning of rf-technique. The characteristics of half-wave dipoles have been calculable very early using the Maxwell and Hertz equations. Therefore the half wave dipole became a reference antenna. The ideal (lossless) half-wave dipole has an isotropic gain of 2.15 dBi and an impedance of 73 Ohm. The directional pattern is circular in the H-plane, “8-shaped” in the E-plane with the maxima perpendicular on the dipole axis.
The half-power beamwidth (-3 dB) is approx. 78°. The impedance of real dipoles is depending on the thickness/length ratio of its elements, typical values are 60-70 Ohm.
Dipoles for industrial applications are available in the frequency range from 30 MHz to up to approx. 4 GHz. The dipole elements are length variable (telescopic) or with fixed length, the latter especially above 1 GHz. The most important applications are test site evaluations (NSA, normalized site attenuation) and the determination of ERP (Effective Radiated Power) respectively EIRP (Effective Isotropic Radiated Power).
UHA 9105
Tuneable UHF – Half – Wave Dipole
300 – 1000 MHz
w. telescopic elements
UHA 9125 C
Tuneable UHF – Half -Wave Dipole
with EMI -Balun
0.75 – 2 GHz with 4 sets of elements
LE = 180, 140, 100, 80 mm
CCA
Carrying and storing case
for 2 x VHAP or 2 x UHAP
cases for other antennas also available.
ILS Dipole
Linear polarized half-wave dipole with 1:1 balun and fixed element length for fieldstrength measurements at instrument landing systems (ILS).
Frequency range:
localizer: 108 – 118 MHz (LOC, LLC)
glideslope: 320 – 340 MHz (G/S)
Gain: 1.5 dBi
TETRA DIPOLE
Linear polarized half-wave dipole with 1:1 balun and fixed element length for measurements at TETRA (terrestrical trunked radio) networks.
Frequency range: 340 – 480 MHz
Gain: typ. 1.5 dBi