The APK-15M Radio Compass is common in many Russian aircraft and was also fitted to the Yak-52. The concept is similar to the western ADF, in that selecting a beacon frequency will enable a pointer on the gyro compass to point directly to the selected beacon if the beacon is within range. The system differs significantly from western ADF instruments in that the frequency of the beacon is not enterable by the pilot. In the rear of the aircraft, 8 beacon frequencies were pre-configurable. The pilot could then select which of the eigth frequencies they required, but not actually change the frequencies themselves.

1. The top control is used to select 4 of the 8 predefined ADF frequencies. In order to get the next 4 frequencies, the pilot selects the second set my using the switch on the top left of the instrument coaming.

2. This switch toggles the ADF system betwen Northern and Southern Hemisphere operation. Northern Hemisphere is 'up' as shown.

3. This switch selects 'Antenna' mode when 'down', normal operation when 'up' as shown.

4. The rotary switch is used to adjust the volume when identifiying the beacon.

5. The green light illuminates when the selector unit is active. Only one pilot can control the ADF unit at a time and so pressing the button below the green light will take control of the ADF and the green light will illuminate to show the pilot they have control.

6. The brown 'test' button is next to the volume control. Pressing this button will make the ADF pointer spin around the dial, proving that the pointer will move. It allows the pilot to reposition the pointer away from a known beacon before releasing the button and allowing the pointer to return to the selected station.