Admiralty Pattern 1900M

This gyro compass is ex Australian Navy. The unit is internally lit and has an electric motor for stabilisation.

I am unsure of the voltage, phase and current of the motor so have not powered it up but it looks clean and tidy – see photos.

The compass has a hard enamal type paint which I have removed off the electrical cover to show the brass beneath.

A sample of this unit is on display at the Royal Greenwich Museum with the description below:

“This gyrocompass repeater has a brass bowl that contains an electric motor for driving the compass card. The bowl is set in gimbals and has two lamp-holder fittings on either side and a card adjustment control at the side. The compass card has a diameter of 8 inches (203 mm) and is divided into degrees, with additional figures printed in reverse for the use of a horizon ring with the repeater. There are also markings at the cardinal and half-cardinal points.
The repeater was originally part of a gyrocompass system used on HMS ‘Triumph’, which was decommissioned in 1981. The repeater would have been linked to a master unit, from which the compass reading came. Gyrocompasses were first successfully developed at the beginning of the 20th century as a solution to the problems of magnetic variation and deviation that are inherent in magnetic compasses. They use the properties of spinning gyroscopes which keep the compass pointing in a fixed direction, usually Earth’s true north. – extract from Royal Greenwich Museum“

Specifications:

• Condition: Used
• Type: Brass Electric Gyro Stabilised Marine Compass Repeater
• Make: Admiralty Pattern
• Series: Mark V Gyro Compass
• Model: 1900-M
• Serial: 8775
• DOM: 1945
• Diameter: 250mm
• Bezel: 200mm diameter
• Construction: Brass
• Mount: Gimbal
• Weight: 11.8kg

Sold AS IS.