R1109 are used to give an amplification of 10 (K1102 open) and an amplification of 1 (K1102 closed). V1110 is closed before K1102 opens (make before break) to get always a defined amplification. R1110 and R1111 are used to give the gate of V1110 the same voltage as the source, so Ugs = OV. The current delivered
