"The input and driver stages Tl and T2 op erate as voltage am plifiers. The output stage, T3 and T4 , operates .in class B to achieve long battery life. D.C. feedback is provided by means of R3 and A.C. feedback by me ans of R3, R4 and C2 . This defines the gain, stabilises the operating point and increases the input impedance.
The biassing of T1 is critical and the values for R 1 and R2 must be adhered to. Should the circuit fail to operate correctly the D.C. conditions may be checked at the base of T3 and T4 and the junction of R6 and R 7."
Downloading of this magazine article is reserved for registered users only.
Discussion (0 comments)