SOTAbeams HF Antenna Trap Kits

SOTABEAM HF Antenna Trap Kits are a clever design with flexible mounting arrangements to make them easy to build and use. They are available in two power levels, 100 watt traps are listed here as SBM-HFAT-101 and 20 watt traps are SBM-HFAT-102. Each kit includes parts to build two (2) traps. Make your portable single band antenna into a multi-bander with our lightweight antenna traps. You decide on the frequency when you build them; recommended range 7 - 25 MHz. Alignment of each trap is accomplished easily with an antenna analyzer.

For QRP super lightweight traps, see SOTAbeams PICO TRAPS for 10 Watts (DX Engineering part SBM-PITK-100).

Included in each SOTABEAMS HF Antenna Trap kit:
-2 x high quality trap PCBs with plated through holes
-4 x 100pF 1kv capacitors (used in series or parallel to give 50pF, 100pF and 200pF options)
-2 x mounting hardware for toroids
-2 x toroids (T94-6 for 100W and a lighter T68-6 toroid for 20W)
-Enameled copper wire to suit the power level

Traps can be used in one of two ways. These SOTAbeams traps can be used either way, it's your choice:

1) By using a trap resonant on the higher frequency that you want your antenna to work on, traps work as an effective isolator. In this application, the trap needs to be resonated in the band. This configuration makes the antenna easy to adjust as the sections do not interact much. In this configuration, our traps show a loss of typically < 0.7 dB.

2) By using a trap resonant between the two bands that you want to use (typically 1 to 2 % percent below the band edge of the higher band), losses are reduced but adjusting the antenna is much more difficult as the two sections interact. In this configuration our traps show a loss of typically < 0.3dB.

We recommend that you resonate your traps at the lowest edge of the band that the trap is to work at. So for a 20m-40m dipole, resonant your trap at 14.0 MHz. This tends to be a reasonable compromise between trap loss and ease of antenna adjustment.

Instructions are linked in the Documents tab on the "More Detail" page.

SOTAbeams HF Antenna Trap Kits Specifications:
PCB Dimensions: 2.599 x 1.181 in. (66 x 30 mm)
Insertion Loss: 0.3 – 0.75 dB depending upon resonant frequency
Impedance at resonance: 20,000 Ohms, typical
Weights: 20 W traps 0.4 oz. (10.6 g), 100 W traps 0.6 oz. (16 g)
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