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1.5kW ICAS Dual Core High Power 1:1 Antenna Tuner Current Balun or Choke

1.5kW ICAS Dual Core High Power 1:1 Antenna Tuner Current Balun or Choke

€206,00 EUR
€206,00 EUR
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Complementary: Stainless Steel (RVS / INOX 316) Mounting Kit available — use the small version for this tuner balun.
All our products are handmade, and fulfilment times may vary depending on order volume. Please allow 2–3 weeks for your order to be completed and shipped.

The 1.5 kW ICAS Dual-Core 1:1 Antenna Tuner Balun / Current Choke is designed for balanced open-wire and ladder-line systems using external tuners. It converts an unbalanced tuner output to a balanced line, maintaining true current symmetry and eliminating common-mode RF that can disturb tuner readings or cause RF feedback.

Related reading:
Correct Use of RF.Guru Antenna Tuner Baluns
Baluns in a Nutshell
How Much Choking Do You Really Need — for RX and TX?

Function

This current-balun design provides the correct balanced-to-unbalanced transition for ladder-line-fed antennas. It uses dual 61 mm ferrite cores wound with Teflon-insulated twin lead, each conductor enclosed in a Teflon sleeve (24 kV/mm) to withstand extreme voltage stress. The four M6 terminals (two for tuner output, two for balanced line) allow a direct, low-loss connection without SO-239 or coax interfaces.

The balun tolerates wide impedance swings found at tuner outputs and maintains high current isolation across its range. It can be used standalone or cascaded with a second unit for full HF coverage.

Variants

160 – 40 m Low-Band Tuner Balun (1.5 kW ICAS)

Optimized for 1.5–15 MHz, delivering high impedance and strong suppression on 160, 80 and 40 m.

Band Choking Impedance (Ω) Impedance-Equivalent dB (from |Zc|)
160 m ≥ 3.5 kΩ ≈ 42.9 dB
80 m ≥ 7.0 kΩ ≈ 48.9 dB
40 m ≥ 8.0 kΩ ≈ 50.1 dB
*Impedance-Equivalent (dB) values are computed directly from |ZCM| using a 50 Ω common-mode source reference. Real antennas almost never present 50 Ω CM, so these values represent the balun’s intrinsic suppression capability — not attenuation under load. See: Why dB Attenuation Specs on Ham Chokes Are a Mess.*

30 – 10 m High-Band Tuner Balun (1.5 kW ICAS)

High-frequency version for 30–10 m balanced loops and tuner-fed doublets.

Band Choking Impedance (Ω) Impedance-Equivalent dB (from |Zc|)
30 m 3.0 kΩ 41.6 dB
20 m 2.5 kΩ 40.0 dB
17 m 2.3 kΩ 39.3 dB
15 m 2.1 kΩ 38.5 dB
12 m 1.9 kΩ 37.6 dB
10 m 1.7 kΩ 36.7 dB
*Impedance-Equivalent (dB) values derived directly from |ZCM| on a 50 Ω common-mode reference. These figures represent intrinsic suppression, not the actual CM impedance of a real antenna system.*

For full 1.5–30 MHz coverage, simply install the low-band + high-band baluns in series. Cascading both raises |Zc| and increases intrinsic suppression by approximately +6 dB per doubling.

Mechanical Characteristics

  • Four M6 stainless terminals (tuner → balun → ladder line)
  • Each terminal isolated with Teflon spacers to eliminate creepage
  • Dual 61 mm ferrite toroids for thermal + magnetic headroom
  • Heat-resistant Teflon twin-lead with 24 kV/mm sleeving
  • INOX 316 hardware
  • UV-resistant polycarbonate enclosure, IP64 sealed
  • Side-mounted terminals for maximum creepage distance
  • Weight: approx. 500 g

Construction Highlights

  • Dual-core architecture for broadband HF choking
  • High-voltage internal coating
  • Fully sealed polycarbonate enclosure with silicone gasket
  • All values are conservative, verified under load
Technical Validation — How We Measure It
Measurements follow true common-mode current injection under load. Residual current is detected with a precision probe to derive Common-Mode Rejection (CMR) in dB — the figure that matters for tuner-fed antennas.

Differential VNA tests do not measure CM behavior. Our EMC-grade dual-probe setup measures the actual CM current reduction your tuner system sees.

Mini-FAQ

  • Q: Can I connect it directly to tuner terminals?
    — Yes. The four M6 posts allow direct tuner → balun → ladder line connections.
  • Q: Are the terminals insulated?
    — Yes. Teflon spacers prevent creepage along the enclosure surface.
  • Q: Which variant do I need?
    — Low-band for 160–40 m; High-band for 30–10 m loops and doublets.
  • Q: Can I use both together?
    — Yes. Cascading covers 1.5–30 MHz and increases suppression.
  • Q: Outdoor safe?
    — Fully sealed, IP64, HV-coated, and designed for harsh environments.

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Written by Joeri Van Dooren, ON6URE — RF engineer, antenna designer, and founder of RF.Guru.
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