Feature: 1. Sound Amplification: Includes sound source access resistors (R2, R3), a volume potentiometer (SW1), a sound amplifier IC (IC1), coupling capacitors (C9), bypass capacitors (C11, C12), an RC filter circuit (R1, C8), and power indicator components (R5, D1). 2. Oscillation Source: Features a common-base modulation transformer oscillator circuit using transistor Q1, generating high-frequency equal-amplitude signals. Frequency is adjustable from 530–1600 kHz via variable capacitor CV. Includes positive feedback network (R10, C19), high-frequency bypass capacitor (C18), power supply filtering and bypass capacitors (C16, C17), and bias resistors (R7, R8, R9). 3. High-Frequency Amplification: Uses transistor Q2 to further amplify the high-frequency signal from Q1. Includes coupling capacitor (C20), high-frequency bypass capacitor (C21), bias resistors (R11, R12), and broadband RF inductor (B2), with secondary output delivering high-frequency voltage. 4. High-Frequency Modulation: Includes audio coupling capacitors (C22, C23), adjustable audio input level control (SW3), negative feedback resistor (R15), and bias adjustment controls (SW2, R14) for improved audio quality. 5. Filter Network: Low-pass filter consisting of inductors (L2, L3) and capacitors (C26, C27) to suppress harmonics and produce a near-sinusoidal waveform compatible with standard antennas. Specifications: Item Type: Medium Wave AM Radio Transmitter Kit Material: PCB Power Supply: 9V DC, 2A, 5.5 mm barrel jack (center-positive) — external power supply required Transmission Frequency Range: 530–1600 kHz (Medium Wave Band) RF Output Power: Adjustable from 20–500 mW; optimal range: 5–10 meters Antenna: Compatible with standard household wire (1.5–2.5 mm² cross-section), 2–5 meters in length — not included Audio Input: 3.5 mm stereo jack (included cable) Compatible Audio Sources: CD players, desktop computers, smartphones, etc. Intended Use: Educational tool for students and hobbyists studying AM transmission principles, wireless signal generation, and analog modulation techniques. Package Includes: 1 × Transmitter board 1 × Screw kit 1 × Instruction manual 1 × 3.5 mm audio cable Note: This kit is intended for educational and experimental use only. It is not certified for commercial broadcast or interference-free operation. Users must comply with local radio transmission regulations.