4O3A HFC4500 Signature Series Antenna Triplexer/Combiners

4O3A HFC4500 Signature Series Antenna Triplexer/Combiners are truly a game changer for SO2R, multi-operator contest stations, DXpeditions, and Field Day operation. They allow a single triband 20/15/10-meter Yagi antenna, fed with one coaxial feedline, to be used by three stations simultaneously, with each station running up to 4.5kW. The 4O3A Signature Series Triplexer System eliminates the need for separate monoband Yagi’s on the 20m, 15m, and 10m bands. Three operators, three stations, and three amps—but only one feedline and one antenna.

The 4O3A HF Triplexer System uses the high-power HFC4500 Combiner, which connects to a triband 20m/15m/10m antenna, and provides dedicated ports for 20m, 15m, and 10m. Each port must be connected to a 4O3A Series S Bandpass Filter. The Combiner is not intended for standalone use.

With the appropriate filters in place, the system provides exceptional band-to-band isolation—typically 72dB or greater, and in some cases exceeding 120dB. This level of isolation enables true simultaneous operation across all three bands without harmful interference. Insertion loss is minimal, typically 0.10 to 0.15dB. Even at high power levels (up to 4.5kW per port), intermodulation distortion remains low, with worst-case RX IMD levels around –7dBm.

When evaluating a 4O3A Triplexer System investment, consider the savings in antennas, towers, feedlines, and maintenance that will accrue. Once you have the Combiner, the system is flexible: you can configure it as a triplexer, diplexer, or use the filters independently with monoband antennas. Especially in large stations or remote setups, this system reduces coaxial cable runs and tower space requirements, freeing up resources for other bands or antennas.

Key Features:

High-Power Multi-Station Operation: Supports up to 4.5kW per band, enabling simultaneous transmission on 20m, 15m, and 10m from three separate stations using a single triband Yagi and one coaxial feedline.

Exceptional Band Isolation: When used with 4O3A Series S Bandpass Filters, provides ≥72 dB to >120 dB of port-to-port isolation—ideal for SO2R and multi/multi contesting.

Efficient Station Design: Eliminates the need for multiple monoband antennas, reducing tower space, feedline runs, and maintenance, while offering flexible configuration as a triplexer, diplexer, or filter bank.

Additional Features and Specifications:

HFC4500 Triplexer (without filters connected)

• Input Ports: 20M, 15M, 10M

• Input Power per Port: 4,500W

• Insertion Loss

  • 0.10dB on 20M

  • 0.10dB on 15M

  • 0.15dB on 10M

• Connectors: UHF SO-239 Female or Type-N

• Dimensions: (WxHxD) 21.654 x 4.724 x 4.724in.(55 × 12 × 12cm)

• Weight: 6.17lbs.(2.8kg)

Attenuation Between Ports (with Filters Connected)

• Input 20M:

  • 15M: ≥ 87dB

  • 10M: 120dB

  • 20M: 104dB

• Input 15M:

  • 20M: 104dB

  • 10M: ≥ 72dB

• Input 10M:

  • 20M: > 120dB

  • 15M: ≥ 72dB

RX IMD Level (Worst Case)

• At 1600W per port: –10dBm

• At 3200W per port: –7dBm