The circuit of this kit is simple and easy to understand, especially suitable for assembly. This circuit is a voltage divider current negative feedback single-stage low frequency small signal amplifier, it is the use of adjustable resistance, two 22K resistance voltage divider fixed base potential; Then the emitter resistance of 220 ohms is used to obtain the current feedback signal, so that the base current changes accordingly, so as to stabilize the static operating point.
Working voltage: DC 6-12V
Board size: 3.05*3.05cm
Single tube amplifier circuit kit, input voltage signal amplification, amplification multiple can be adjusted, triode amplifier principle. Can be used as the basic kit of electronic technology, suitable for electronic hobbyists to start using.
Circuit principle: this circuit is a voltage divider current negative feedback single-stage low frequency small signal amplifier, it is using RP, R1, R2 voltage divider fixed base potential; Then the emitter resistance R4 is used to obtain the current feedback signal, so that the base current changes correspondingly, so as to stabilize the static operating point. Q is a crystal triode, RP and R1 are the upper bias resistors, R2 is the lower bias resistors, the power supply voltage after voltage division to provide the base current. R3 is the collector resistance, R4 is the emitter resistance, and C3 is the emitter resistance bypass capacitor, providing the channel of AC signal, reducing the loss in the process of amplification, so that the ac signal does not reduce the amplifier’s amplification ability due to the presence of R4. C1 and C4 are coupling capacitors, while C2 is vibration elimination capacitor, which is used to eliminate self-excitation that may be generated by the circuit.
Matters needing attention:
1. Note that the components on the board are welded from the small ones and then the large ones.
2. Some components, such as resistors and capacitors, are temporarily out of stock. We will send them with other values of symbol circuit principle to replace them. It’s the same effect.