Đã được đăng vào 17/05/2019 @ 14:52
Mạch điều chỉnh âm lượng (Audio Fader)
Nguyên văn tiếng Anh:
In this circuit, Q1 is a simple amplifier that has its gain controlled by a variable emitter resistance supplied by FET Q2.
In the up position of S1, C3 discharges through R5 and the gain of Q1 decreases because Q2 is driven toward cut-off. In the down position, Q2 conducts more, depending on the setting of R6, which causes a gain increase.
By varying R5 or C3, various fade rates can be obtained. (Hands-On Electronics 8/87, p. 93)