Makrofon Zollner M75F/260Hz Air Horn

Makrofon Zollner M75F/260Hz Air Horn BSH 4615/6020395/09 Kl. II/III

The ZOLLNER Makrofon M75F/260Hz (Type Approval BSH 4615/6020395/09, Class Kl. II/III) is a compressed-air diaphragm acoustic transmitter engineered in Kiel, Germany, for primary shipboard fog, maneuvering, and warning signaling. Built strictly to satisfy IMO COLREG 1972 Annex III acoustic requirements, this transmitter covers both Class II vessels (75 m to < 200 m LOA) and Class III vessels (20 m to < 75 m LOA).

The M75F/260Hz generates a fundamental frequency of 260 Hz with a 1/3rd-octave band sound pressure level of 138 dB at 1 meter. Its acoustic profile produces rich higher-order harmonics so human watchkeepers perceive the parent 260 Hz pitch even when heavy engine-room exhaust or gale-force wind masks the fundamental tone. Constructed from seawater-resistant sheet copper and marine-grade non-corrosive alloys, the assembly prevents salt-laden atmospheric pitting and stress corrosion cracking on exposed mastheads and radar pedestals.

Model Details

• Manufacturer: ZÖLLNER Signal GmbH (Radewisch 40, 24145 Kiel, Germany)
• Series / Type: MAKROFON M75F / 260 Hz (Configurations: ZVE, ZVEE, ZVEEH, HVE)
• Manufacturer Part Number (MPN) / Base Assembly No.: 0103144 (Makrofon M75F/260 core transmitter) / BSH 4615/6020395/09
• BSH Type Approval Stamp: BSH 4615/6020395/09
• Vessel Class Designation: Kl. II / III (Class II: 75 m to < 200 m; Class III: 20 m to < 75 m)

Features

1. Dual-Class Acoustic Compliance (Kl. II & III): Tuned to a 260 Hz fundamental frequency that sits squarely inside the overlapping admissible frequency bands for both Class II (130–350 Hz) and Class III (250–700 Hz) vessels under COLREG 1972 Annex III.
2. Wide 6–40 Bar Pneumatic Operating Envelope: Accepts direct shipboard working air or high-pressure starting air reductions between 6 and 40 bar without diaphragm chatter or over-pressure distortion.
3. Redundant Triple-Mode Actuation (ZVEEH Architecture): Supports primary bridge-console electric solenoid release, secondary 24 V DC emergency battery solenoid release (eliminating long mechanical pull-wire runs), and direct mechanical hand-rope lever operation.
4. Thermostatic Anti-Condensation Heating: Integrated self-regulating thermostat heater prevents moisture condensation inside the operating valve chamber and stops freezing during sub-zero Arctic or North Atlantic transits.
5. Marine-Grade Sheet Copper & Non-Ferrous Construction: Manufactured in Germany using coated sheet copper for the acoustic projector horn and seawater-resistant alloys for the valve housing, achieving IP56 weatherproof integrity.

Applications

• Commercial Ocean-Going Vessels (Class II, 75 m to < 200 m): Primary forward or mainmast whistle for coastal cargo ships, feeder container vessels, product tankers, offshore supply vessels (OSVs), and Ro-Ro ferries.
• Coastal & Harbor Craft (Class III, 20 m to < 75 m): Primary acoustic signaling transmitter for harbor tugs, pilot boats, research vessels, fishing trawlers, and large motor yachts.
• Secondary / Forward Whistle on Large Vessels (≥ 200 m): Installed on the forecastle mast as part of a combined whistle system separated by more than 100 meters to meet directional SPL requirements.
• Industrial & Shore-Based Hazard Alarms: High-decibel pneumatic warning horn for offshore oil and gas platforms, LNG bunker terminals, refineries, chemical plants, power stations, and airport perimeter alert systems.

Part Number Cross-References

• BSH Type Approval Reference: BSH 4615/6020395/09
• ZÖLLNER Core Transmitter Code: 0103144 (Makrofon M75F/260)
• ZÖLLNER Signal Set Reference: 01049321 (Makrofon Signal Set M75F/260 ZVEEH, Class II+III)
• ZÖLLNER Datasheet Identifiers: SW133 / 06100087EN6 / 01414917-EN-02
• Variant Suffix Codes:
  • M75F/260 ZVE: Single electric solenoid + hand pull-rope lever
  • M75F/260 ZVEE: Dual electric solenoids (Main + 24 V DC Emergency) + pull-rope lever
  • M75F/260 ZVEEH: Dual electric solenoids + thermostat anti-condensation heating
  • M75F/260 HVEF: Heated variant with integrated F4 filter assembly
• Distributor / Industrial Cross-Refs: ERIKS 13461584 (24 V DC / 240 V AC ZVEEH), ERIKS 13461598 (240 V AC ZVE), ERIKS 13461601

Frequently Asked Questions

What does the BSH 4615/6020395/09 Kl. II/III marking on the Zollner M75F/260Hz mean?

BSH 4615/6020395/09 is the official marine type-approval certificate number issued by Germany’s Federal Maritime and Hydrographic Agency (Bundesamt für Seeschifffahrt und Hydrographie). The Kl. II/III designation confirms that the 260 Hz acoustic output and 138 dB sound pressure level satisfy IMO COLREG 1972 Annex III rules for both Class II vessels (75 m to under 200 m in length) and Class III vessels (20 m to under 75 m in length).

Can the Zollner Makrofon M75F/260Hz operate directly on a 30 bar shipboard starting air line?

Yes. The Makrofon M75F/260Hz is engineered to operate across a continuous pneumatic pressure range of 6 to 40 bar. You can connect it directly to either a 7–10 bar general service air line or a 30 bar main starting air reduction line without installing a dedicated pressure regulator, provided a moisture/particulate filter (Type F3.1 or F4) is fitted upstream.

What is the difference between M75F/260 ZVE, ZVEE, and ZVEEH variants?

The suffix letters identify the factory-fitted electrical options: ZVE includes a single electric solenoid valve plus a mechanical hand pull-rope lever; ZVEE adds a second 24 V DC electromagnet for emergency battery operation (eliminating mechanical pull-wires to the wheelhouse); and ZVEEH incorporates both the emergency 24 V DC solenoid and a thermostat-controlled anti-condensation heater to prevent valve icing.

What pipe size and material should be used to connect compressed air to the M75F/260Hz?

ZÖLLNER equips the M75F/260Hz inlet with a GE10LR metric compression fitting designed for 10 mm outer diameter (OD) tubing. Seamless marine-grade copper tubing is strongly recommended over galvanized steel to prevent internal rust flakes from fouling the operating valve seat.

Which ZÖLLNER automatic whistle controller works with the M75F/260Hz?

The M75F/260Hz pairs directly with the ZÖLLNER Signal Automaton 6+S (available in 24 V DC or 230 V AC 1-phase versions) to execute automated COLREG Rule 35 fog and restricted-visibility signals alongside a synchronized maneuver signal lamp such as the Type TS 1a – 4392a.