The Active-Filter Tuned Oscillator

** Circuit Description **

* op-amp subcircuit

+++++ place uA741 op-amp subcircuit here (see Fig. 12.1) +++++

** Main Circuit **
* power supplies
Vcc 8 0 DC +15V
Vee 9 0 DC -15V
* high-Q filter circuit
Xopamp1 3 5 8 9 1 uA741
Xopamp2 7 5 8 9 4 uA741
R1 2 3 50k
C1 3 0 16nF IC=0V
R2 3 4 10k
C2 4 5 16nF IC=0V
R3 5 1 10k
R4 1 7 10k
R5 7 0 10k
* diode limiter circuit 
D1 0 2 D1N4148
D2 2 0 D1N4148
R6 1 2 10k
* model statement
.model D1N4148 D (Is=0.1p Rs=16 CJO=2p Tt=12n Bv=100 Ibv=0.1p)
** Analysis Requests **
.OPTIONS itl5=0
.TRAN 20us 50ms 45ms 20us UIC
.FOUR 1kHz V(1)
** Output Requests **
.PLOT TRAN V(1) V(2)
.probe V(1) V(2)
.end