Gyrocompass is a type of non-magnetic compass that uses planetary rotation as a medium to determine geographic direction automatically. Gyrocompass is widely used for navigation activities on ships. One of Gyrocompass usually used for ship in Indonesia is Gyrocompass GM-20 Tokyo Keiki.
This Gyrocompass GM-20 Tokyo Keiki series is a compact version of the ES Series, and is chiefly used in small vessels. Thanks to TOKYO KEIKI’s state-of-the-art technology, Gyrocompass GM-20 Tokyo Keiki instrumentation for heading reference is now available at reasonable cost to operators of small commercial vessels and fishing boats. The advantages of gyroscope technology offered by the specially designed GM-20/21 eliminates the inconveniences associated with conventional magnetic compasses.
- Compact Design The GM-20/21 measures only 228 x 321 x 377mm, so it can be easily installed on fishing boats and other small commercial vessels.
- Low Power Consumption Power consumption is only 50 VA (for master compass)
- Ease of Operation
- Direct Reading and Synchro Output Direct reading simplifies use considerably, and synchro output offers means for low-cost autopilot steering.
- Three Repeater Compass Circuits
- Automatic Preset Startup
- A 24-hour timer permits automatic startup.

Now, thanks to the meployment of state-of-the-art TOKIMEC technology, even operatore of small commercial vessels and fishing doats can enjoy the advantages of a gyrocompass for heading reference-and do so at reasonable cost. Of course, as the specially designed GM-20/21 gives gyrocompass benefits, it also eliminates the inconveniences associated with conventional magnetic compasses.
The GM-20/21 features a synchro output, which can be used to drive the companion TOKIMEC PR-1500 Steering Control for decidedly low cost autopilot steering. There’s also an automatic preset startup feature with a 24-hour range, so the GM-20/21 can be made all ready to go for the next trip. In addition, if a synchro amplifier is used with the GM-21, up to three repeater compasses can be connected. The GM-20/21 is comprised of a master compass, which is normally mounted on top of the static inverter. If available space is limited, the static inverter can be remotely located on the bulkhead.

GYROCOMPASS GM-20 TOKYO KEIKI FEATURES
● Compact Design
The GM-20/21 measures only 228×321×377 mm, so it can be easily installed on fishing boats and other small commercial vessels.
● Low Power Consumption
Power consumption is only 50 VA (for master compass).
● Ease Of Operation
● Direct Reading And Synchro Output
Direct reading simplifies use considerably, and synchro output provides forlow-cost autopilot steering.
● Three Repeater Compass Circuits
● Automatic Preset Startup
A 24-hour timer permits automatic startup.


GYROCOMPASS GM-20 TOKYO KEIKI SPECIFICATION
Signal Input | |
Power Supply | AC 100/110, 1φ, 50/60 Hz, 60 VA (for repeater compass)
DC 24 V, 2 A (with only master compass running) |
Voltage Fluctuation | ±20% |
Ambient Temperature North-seeking | +50 ℃ ― -20 ℃ |
Accuracy | Within ±2゜ |
Follow-up Accuracy | Within ±0.1゜ |
Setting Time | Less than 4 hours |
Mechanical Freedom | ±45 ゜Maximum Turning |
Follow Up Speed | Turning ratio of 10 sec/rev |
Repeater | 90 synchro motor (3 circuits) |
Read more : Marine Gyrocompass TG-8000/8500 Tokyo Keiki