Antenna Project – 2m Halo for 144.2 MHz

Hombrew 2m Halo antenna for 144.2 MHz SSB and WSPR weak signal propagation. Polarisation is horizontal while the radiation pattern is omnidirectional.

Radiator and gamma match are 3/8 inch copper tube. 🙂

Dimensions:

• Loop diameter: 340 mm
• Open end spacing: 40 mm
• Gamma rod: 200 mm length of 16 gauge AWG solid copper insulated wire.
• Gamma capacitor tube length: 100 mm
• Capacitance between the rod and the copper tube is 24.7 pf.
• Gamma clamp: 6 mm square brass bar
• Gamma clamp spacing: 48 mm
• Gamma clamp position: 180 mm from the center of the loop

Adjust the gamma match for a low VSWR.

I will apply a generous coating of pcb enamel to the exposed copper and brass elements.

2m Halo – Feedpoint BNC socket. The center of the loop is wired to the BNC ground terminal.

2m Halo gamma rod – solid copper wire which fits neatly inside the copper tube. Capacitance 24.7 pf.

2m Halo gamma arm – 48 mm spacing

2m halo gamma arm – 2 x 6 mm square brass rod.

Open end spacing 40 mm

2m Halo Loop VSWR 4 MHz scan – center frequency 144.2 MHz

Last update: 23 December 2020