Easter egg

1. Patch dummy cables to the FM and LEVEL inputs to disable the internal normalization.
2. Press the top button (mode, labelled A in the manual) for one second. All LEDs light up in yellow.
3. Press the top button again for one second. All LEDs light up in green.
4. Press the bottom button (range, labelled B in the manual) for one second. All LEDs should light up in red.

An oscilloscope in X-Y mode will show a drawing of a pair of peacocks when visualizing the UNI and BI outputs.