The use of the erhu tuner is relatively simple. Turn on the erhu tuner and pull the erhu outer string and open string. The software will indicate the current pitch and frequency in the form of a dial. When the pointer points to the middle of the dial, the tuning is completed. 

The specific usage is as follows:

1. First, press the red button to turn on the tuner, and then press the M button to adjust the preparation to twelve equal laws.

2. Rotate the tuner, adjust it to a suitable angle, and clamp it on the erhu rod.

3. After the erhu tuning is done, start using the tuner to find the sound. There are too many tones. If it is in the key of F, you can press the cut position of the key of F, and the place where the index finger is pressed makes the tones of 1 and 5.

4. Then move the bow and pull the inner string, slightly move the position of the hand, until the tuner displays the key of F, and the color is displayed in green, the positions of 1 and 5 of the F key are determined. The other sounds are in order. When practicing by yourself, you can use this method from time to time to adjust your pitch, so that you won't deviate too much.