TerraBooster2 — Active shielded 'Loop on ground' — 500KHz - 30MHz

Listen to our SDRs

The TerraBooster2 is a cutting-edge HF active shielded H-field loop-on-ground system in four sizes: Mini (16 m), Medi (32 m), Maxi (56 m) and Xtreme (84 m, unshielded wire). It’s engineered for exceptionally low-noise reception across HF.

All shielded models use RG178B/U coax for the loop element. The Xtreme uses antenna wire (unshielded). The braid of the RG178B/U coax is referenced to ground through an integrated RF filter (shielded versions), dramatically lowering received noise versus passive LoG antennas.

Key Features

• Dual MMIC devices in push-pull for high dynamic range
• Very low noise figure and high sensitivity
• +41 dBm IIP3 (third-order intercept)
• Operating range: 500 kHz – 30 MHz
• RF-shielded braid design with filtered ground reference (Mini/Medi/Maxi)
• Built-in RF limiter + ESD protection
• Integrated wideband common-mode choke on the feed
• FM broadcast notch + 50 MHz low-pass to keep out-of-band energy out
• Internal regulated rail: 10 V
• Mild, useful directionality

What’s Included

• TerraBooster2 Active Unit (Mini / Medi / Maxi / Xtreme as selected)
• RG178B/U receiving element: 16 m (Mini), 32 m (Medi), 56 m (Maxi) — Xtreme includes 84 m of antenna wire
• Bias-T with integrated line isolator (13.8 V input, F-type RF to SMA output)
• SMA-to-BNC adapter cable
• Open-ended PowerPole DC cable
• 2× High-impedance RVS ground pegs (all versions)
• An RC filter to bleed-off static an noise for the shielded versions !

Technical Specifications

Design Philosophy

TerraBooster2 uses a shielded loop (Mini/Medi/Maxi) to isolate the element from local E-field trash. The loop braid is tied via a controlled, high-impedance RF filter to ground, improving SNR without importing common-mode noise. The Xtreme trades some noise immunity for higher absolute capture and can approach Beverage-like receive gain on upper HF.

All versions exhibit better balance and reduced local pickup versus simple wire loops. TerraBooster2 remains compact and essentially omnidirectional, unlike a long, directional Beverage.

Directional Characteristics

TerraBooster2 shows a broad cardioid-like response: strongest reception is roughly perpendicular to the loop, with slightly reduced sensitivity in line with the loop ends. Rotating the loop by ~90° can suppress localized noise or enhance a target direction.

Typical layouts

1. Single unit — aim for max sensitivity broadside to desired paths.
2. Two units at 90° — select the quieter/better direction by switching.
3. Opposing pair (“X”) — balanced dual-direction coverage with two feeds.

Mounting & Placement

• Lay flat on the ground (or slightly elevated). Keep away from buildings and electronics to minimize EMI.
• Provide a proper high-impedance path to ground for the shielded loop braid (Mini/Medi/Maxi).
• Avoid routing cables near power lines. Use quality line isolation on the feedline.
• RVS high-impedance ground pegs simplify the shield reference and common-mode bleed path.

Model Comparison

Loop on Ground — Elevation & Total Gain (Indicative)

Values are modeled (free-space average ground). Actual performance varies with soil and environment.

Grounding Advice

The TerraBooster2 includes two dedicated RVS ground pegs:

• Center reference — connected to the push-pull amplifier’s center pin. This peg is required for all versions.
• Shield reference — connected through the integrated filter to the loop braid. This peg is required for shielded versions (Mini/Medi/Maxi).

Place the two pegs about 20 cm apart in the soil to minimize interaction and ensure clean high-impedance bleed paths. For additional noise suppression, an optional RX 75 Ω line isolator can be placed before the coax enters the shack.