Lodestar IID
This is a servo motor driven ship-board MF direction finding receiver, built by Marconi. It operates from either 110 or 200 Volts DC or 115 or 230 Volts AC. It can be interfaced to compass repeaters.
COMMENTARY
The Loadstar 2D is a fully automatic direction finding receiver covering MF and the 2182 HF marine emergency frequency. Alternately the receiver may be operated manually.
The receiver interfaces to a Bellini-Tosi fixed loop and a 25ft vertical aerial mounted in appropriate places on the ship.
When a signal of 50uV/m or greater is detected the goniometer coil is rotated by a servo motor to detect the correct bearing. Due to the arrangement of the circuit the true null rather than its reciprocal will always be detected.
TECHNICAL SPECIFICATIONS
Frequency Range: 250-550kHz, 2182kHz
Bandspread: 285-315kHz
Power Supply: 110DC or 220DC or 115VAC or 230VAC
Sensitivity: 40uV for +-1 degree accuracy
Weight: 89lbs
CONSTRUCTION
Construction is quite solid. The unit is designed to be mounted on shock mounts.
Below: Lodestar 2D top view. The servo motor and gearing is at centre right of photo.
Below: Rear left view. PC cards are used for the majority of the circuitry.
