Version 4 SHEET 1 1284 908 WIRE -768 -448 -992 -448 WIRE -768 -352 -768 -448 WIRE -768 -352 -784 -352 WIRE -784 -320 -784 -352 WIRE -992 -224 -992 -448 WIRE -192 -160 -464 -160 WIRE 16 -160 -192 -160 WIRE 288 -160 16 -160 WIRE 544 -160 288 -160 WIRE -784 -144 -784 -240 WIRE -464 -128 -464 -160 WIRE -192 -32 -192 -160 WIRE 544 -32 544 -160 WIRE -992 0 -992 -144 WIRE -784 0 -784 -64 WIRE -464 0 -464 -48 WIRE 16 16 16 -160 WIRE -192 64 -192 48 WIRE -96 64 -192 64 WIRE -48 64 -96 64 WIRE -192 96 -192 64 WIRE 288 96 288 -160 WIRE -304 144 -640 144 WIRE -256 144 -304 144 WIRE 16 144 16 112 WIRE 144 144 16 144 WIRE 224 144 144 144 WIRE -640 192 -640 144 WIRE 496 224 464 224 WIRE 544 224 544 48 WIRE 544 224 496 224 WIRE 288 240 288 192 WIRE 288 240 240 240 WIRE 336 240 288 240 WIRE 384 240 336 240 WIRE 544 240 544 224 WIRE 464 288 464 224 WIRE 464 288 448 288 WIRE 480 288 464 288 WIRE 112 304 32 304 WIRE 240 304 112 304 WIRE -192 352 -192 192 WIRE -640 368 -640 272 WIRE 384 384 384 336 WIRE 544 384 544 336 WIRE 32 400 32 384 FLAG -192 352 0 FLAG -464 0 0 FLAG -640 368 0 FLAG 384 384 0 FLAG 544 384 0 FLAG -992 0 0 FLAG -784 0 0 FLAG -304 144 in FLAG -96 64 out1 FLAG 144 144 out2 FLAG 336 240 out3 FLAG 496 224 bias FLAG 32 400 0 FLAG 112 304 speaker SYMBOL npn 224 96 R0 SYMATTR InstName Q1 SYMATTR Value 2N3904 SYMBOL npn -256 96 R0 SYMATTR InstName Q2 SYMATTR Value 2N3904 SYMBOL res -208 -48 R0 SYMATTR InstName R5 SYMATTR Value 10k SYMBOL voltage -640 176 R0 WINDOW 123 0 0 Left 2 WINDOW 39 24 124 Left 2 SYMATTR InstName V1 SYMATTR Value SINE(0.6 20m 1k) SYMBOL voltage -464 -144 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 5 SYMBOL npn 448 240 M0 SYMATTR InstName Q3 SYMATTR Value 2N3904 SYMBOL res 16 288 R0 SYMATTR InstName R4 SYMATTR Value 8 SYMBOL npn -48 16 R0 SYMATTR InstName Q5 SYMATTR Value 2N3904 SYMBOL cap 224 240 R0 SYMATTR InstName C1 SYMATTR Value 10µ SYMBOL res 528 -48 R0 SYMATTR InstName R7 SYMATTR Value 100 SYMBOL voltage -992 -240 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V3 SYMATTR Value 5.6 SYMBOL res -800 -336 R0 SYMATTR InstName R9 SYMATTR Value 33k SYMBOL res -800 -160 R0 SYMATTR InstName Microphone SYMATTR Value 10.5k SYMBOL npn 480 240 R0 SYMATTR InstName Q4 SYMATTR Value 2N3904 TEXT -608 336 Left 2 !.tran 0 1005m 1000m 0.1m TEXT -640 88 Left 2 ;Use real DC offset of 700 mV TEXT -768 -208 Left 2 ;Output voltage (0.7 V DC), good swing TEXT -792 232 Left 2 ;Test input