VHF Folded Dipoles - Professional Series

Models FDA-SM, FDB-SM & FDE-SM

This range of folded dipoles provides broadband unity gain and is designed for general purpose base station and repeater sites. All models have vertically polarised radiation patterns which can be offset by locating the dipole at specific distances from a metallic support structure or by using a reflector.

The folded dipole models are constructed from heavy duty extruded aluminium tube with a rugged cast aluminium centre clamp. The clamp is attached to the boom with 3 radial bolts to provide a reliable connection. All hardware is stainless steel and to increase the corrosion resistance the aluminium element and boom are silver anodised.

Each dipole is fitted with a RG213 coax tail terminated with an N plug connector, the tail length being 1m from the end of the boom. The folded dipole element is DC grounded. Suitable clamps to use are available. The Pole Mount Clamp (CLPM) for attaching to a wooden pole, or the Cross Clamp (CLCR) to mount to a rigging pipe mounting support.


Model FDA-SM FDB-SM FDE-SM
Frequency Range (MHz) 80-88 88-108 110-180
Bandwidth (MHz) 12 20 30
Input Impedance (Ohms) 50
Return Loss (dB & VSWR) >-14dB 1.5:1
Maximum Power (W) 350 250
Cable Type & Length RG58, 1 Metre
Max Element Length (m) 1.6 1.5 0.9
Boom Length (m) 1.5 1.0
Boom Diameter (mm) 48 38
Projected Area (m2) 0.155 0.145 0.075
Wind Loading at 150 km/h (N) 170 160 80
Weight (kg) 4.5 4.2 2

FDE-SM Graph
FDA-SM