These vertically polarized antennas for FM broadcasting applications are intended for use where low wind loadings are required. They are designed to be sidemounted to a tower leg or pole and optional mounting brackets are available for this purpose. The 818 series are fabricated from stainless steel and will handle up to 5kW per bay. Multiple element arrays are supplied as a complete package including power dividers and distribution cables. An optional input tuner ensures optimum VSWR performance after installation as it enables the effects of tower steelwork to be eliminated. Beam tilt and null fill can be provided on request. The 818 series can be arrayed in multiple bays as required.
FEATURES / BENEFITS
Rugged construction for maximum corrosion protection
Multichannel use if required
Low windload to minimize tower or mast costs
Temperature range -40 to +60 degrees C available.
818 Series showing 818-4 Antenna
Band II (VHF) FM 818-4 Sidemount Antennas
87.5 - 108
Nominal Gain (Mid-band)
Azimuth Radiation Pattern
Omni directional + 3 dB Note 1
Typically 20 over 6MHZ bandwidth . Tunable within band
Input/Power Rating Comment
Power ratings are for single input 7-16 input models. 7/8" input limited to 5 kW. Dual input cavity versions can provide higher power ratings. Contact RFS for details. Connector types and impedance may be varied to suit customer requirements, contact RFS for details.
Effective Area Front (full antenna) with 12.5mm(0.5") Radial Ice
0.80 (8.6) Note 3
Effective Area Power Divider
0.13 (1.4) Note 3
Effective Area Comment
Note 3 Connecting cables are not included in calculations - 0.03sq m. per metre length should be allowed.
Wind Load @ 50 m/sec Front
Wind Load Comment
Power divider included and considered adjacent to antennas. Calculated in accordance with AS1170-1989, Part 2:" SAA Loading Code - Wind Forces".
10 - 25 (1.5 - 3.6) 7/8" EIA Version
100 (15) 7/8" EIA Version
Shipping Weight, Kg (lb)
Azimuth Radiation Pattern (Typical)
Vertical Radiation Pattern
External Document Links
Note 1 When antenna is mounted on a mast/tower with a face width of less than 150mm (5.9""). Note 2 Input power is limited to 5kW if a 7/8"" connector is used, 4.0kW for 7-16 DIN connector. Note 3 Connecting cables are not included in calculations - 0.03sq m. per metre length should be allowed. Note 4 Power divider included and considered adjacent to antennas. Note 5 Calculated in accordance with AS1170-1981, Part 2 ""SAA Loading Code - Wind Forces"".