Antenna for amateur 2 m repeaters 144-146 MHz : IK-Telecom
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Antenna for amateur 2 m repeaters
144-146 MHz

If you are installing the repeater on the high mountain at the tough weather conditions or on the top of the broadcasting radio station mast than it is better not to apply the conventional antennas covered by the glass-fiber cases. They may be fast broken under the influence of the ice and wind. In these conditions we recommend to use highly reliable antennas based upon the loop aluminum dipoles D4 VHF (2 m). They are made of the thick tube with the application of Argon welding. They possess a polymeric coating, are fully grounded by the direct current and do not need to be tuned.

Antenna D4 VHF represents folded Pistolcors dipoles. Its primaries: wide operating band and nearly circular pattern. Welded construction of dipole eliminates possibility of intermodulation. Emitting unit directional pattern can be slightly corrected by changing distance from it to mast. Collapsible construction provides easy antenna mounting and dismounting

Antenna D4 VHF

Electrical specifications
Model D4 VHF
Operating frequency band, MHz 136-174
VSWR, not more than 1,5
Gain OMNI, dBd 6
OFFSET, dBd 9
Sector in vertical plane , -3dB 18°
Impedance, Ohm 50
Max. power input, W 400
Mechanical specifications
Model D4 VHF
Mass, kg 10,4
Height/Length, M 5
Construction material Aluminium alloy
Mast diametr, mm 38-65
Rated wind velocity, m/s 45
Wind loading area, m2 0,29
Load of side wind 45 m/s, H 335
Rated wind velocity with 0.5" icing, m/s 28
Temperature range, °C from -50 to +50
Connector N-female

D4 VHF in H-plane, OMNI (1/2λ)

D4 VHF in H-plane, OFFSET (1/4λ)

D4 VHF in H-plane, OFFSET (1/8λ)

Finland, Pulsa