Features: This circuit board microphones can also be connected to external, and adjusting the volume knob can change the volume level. , Basic frequency signal, frequency doubling, high power amplification. frequency doubling circuit to make the frequency more stable and reduce the frequency drift by human inductions. Suitable for electronic information technology, high-performance electronic circuit experiments and testing, with detailed instructions Specifications: Frequency 88~108MHz Circuit board size: mixed Types: assembled/reassembled Note: Due to lighting effects and shooting angle problems, there are certain tolerances in the product, please understand. Please allow 0-1 cm error due to manual measurement. Package includes: 1 set FM transmitter DIY module We always adhere to the customer-centered service philosophy and strive to provide you with the best after-sales service.