Version 4
SHEET 1 880 680
WIRE 272 0 224 0
WIRE 336 0 272 0
WIRE 480 0 416 0
WIRE 544 0 480 0
WIRE 640 0 624 0
WIRE 224 16 224 0
WIRE 272 16 272 0
WIRE 480 64 480 0
WIRE 224 112 224 96
WIRE 272 112 272 96
WIRE 272 112 224 112
WIRE 416 112 272 112
WIRE 224 128 224 112
WIRE -144 160 -176 160
WIRE 176 192 0 192
WIRE 480 208 480 160
WIRE 544 208 480 208
WIRE 592 208 544 208
WIRE 704 208 672 208
WIRE 736 208 704 208
WIRE -144 224 -256 224
WIRE 480 240 480 208
WIRE 544 240 544 208
WIRE 736 240 736 208
WIRE -256 256 -256 224
WIRE -176 256 -176 160
WIRE -144 256 -176 256
WIRE -256 352 -256 336
WIRE -176 352 -176 256
WIRE -176 352 -256 352
WIRE 224 352 224 224
WIRE 224 352 -176 352
WIRE 480 352 480 320
WIRE 480 352 224 352
WIRE 544 352 544 304
WIRE 544 352 480 352
WIRE 736 352 736 304
WIRE 736 352 544 352
WIRE -256 368 -256 352
FLAG -256 368 0
FLAG 640 0 0
FLAG 704 208 out
SYMBOL njf 176 128 R0
WINDOW 0 58 13 Left 2
WINDOW 3 25 48 Left 2
SYMATTR InstName J1
SYMATTR Value BF245A
SYMBOL voltage -256 240 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value SINE({ampl} {ampl*0.7} 2k)
SYMBOL SpecialFunctions\\modulate -144 160 R0
WINDOW 0 0 -81 Left 2
WINDOW 3 0 -53 Left 2
SYMATTR InstName A1
SYMATTR Value Mark=1Meg Space=1Meg
SYMBOL npn 416 64 R0
WINDOW 0 -25 72 Left 2
WINDOW 3 -31 113 Left 2
SYMATTR InstName Q1
SYMATTR Value BC547C
SYMBOL cap 528 240 R0
SYMATTR InstName C2
SYMATTR Value 10n
SYMBOL voltage 528 0 R270
WINDOW 0 32 56 VTop 2
WINDOW 3 -32 56 VBottom 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value 8V
SYMBOL res 432 -16 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R4
SYMATTR Value 680
SYMBOL res 496 224 M0
SYMATTR InstName R2
SYMATTR Value 4.7k
SYMBOL ind 240 0 M0
SYMATTR InstName L1
SYMATTR Value 470µ
SYMBOL res 256 0 R0
SYMATTR InstName R1
SYMATTR Value 4.7k
SYMBOL res 688 192 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 1k
SYMBOL cap 720 240 R0
SYMATTR InstName C1
SYMATTR Value 10n
TEXT -224 24 Left 2 !.tran 0 10.1m 100u 50n
TEXT -192 376 Left 2 !.param ampl=50mV