Version 4 SHEET 1 2032 1128 WIRE -1216 -224 -1440 -224 WIRE -1008 -224 -1216 -224 WIRE -496 -224 -1008 -224 WIRE 32 -224 -496 -224 WIRE 624 -224 32 -224 WIRE 896 -224 624 -224 WIRE -1440 -128 -1440 -224 WIRE -1216 -128 -1216 -224 WIRE -544 -64 -576 -64 WIRE -432 -64 -464 -64 WIRE 960 -48 928 -48 WIRE -1440 0 -1440 -48 WIRE -496 0 -496 -224 WIRE 32 0 32 -224 WIRE -1440 16 -1440 0 WIRE -672 16 -1440 16 WIRE -576 16 -576 -64 WIRE -576 16 -592 16 WIRE -528 16 -576 16 WIRE 0 16 -16 16 WIRE 624 16 624 -224 WIRE 896 16 896 -224 WIRE -1552 32 -1856 32 WIRE -432 32 -432 -64 WIRE -432 32 -464 32 WIRE -384 32 -432 32 WIRE -112 32 -112 -48 WIRE -112 32 -320 32 WIRE -32 32 -112 32 WIRE 160 32 64 32 WIRE 448 32 416 32 WIRE 576 32 576 -48 WIRE 576 32 528 32 WIRE 592 32 576 32 WIRE 752 32 736 32 WIRE 848 32 848 -48 WIRE 848 32 832 32 WIRE 864 32 848 32 WIRE -528 48 -560 48 WIRE -32 48 -32 32 WIRE 0 48 -32 48 WIRE 656 48 656 -48 WIRE 736 48 736 32 WIRE 736 48 656 48 WIRE 960 48 960 -48 WIRE 960 48 928 48 WIRE 992 48 960 48 WIRE 1136 48 1136 -128 WIRE 1136 48 1072 48 WIRE 1152 48 1136 48 WIRE -1440 64 -1440 16 WIRE -1216 64 -1216 -48 WIRE -672 64 -1216 64 WIRE -560 64 -560 48 WIRE -560 64 -592 64 WIRE 592 64 544 64 WIRE 864 64 816 64 WIRE -560 96 -560 64 WIRE -16 96 -16 16 WIRE 160 96 -16 96 WIRE 352 96 160 96 WIRE -1920 112 -2016 112 WIRE -1856 112 -1856 32 WIRE -1696 112 -1792 112 WIRE -1552 112 -1552 32 WIRE -1552 112 -1616 112 WIRE -1504 112 -1552 112 WIRE -1072 112 -1152 112 WIRE -944 112 -992 112 WIRE -864 112 -944 112 WIRE 816 112 816 64 WIRE 816 112 752 112 WIRE -496 128 -496 64 WIRE 816 128 816 112 WIRE 160 144 160 96 WIRE -1312 160 -1440 160 WIRE -1216 160 -1312 160 WIRE -864 176 -864 112 WIRE -560 176 -864 176 WIRE -1792 192 -1792 112 WIRE 352 192 352 176 WIRE 544 192 544 64 WIRE 544 192 352 192 WIRE 32 240 32 64 WIRE 160 240 160 224 WIRE 624 240 624 80 WIRE 896 240 896 80 WIRE -1312 336 -1312 160 WIRE -1600 480 -1600 464 WIRE -1312 480 -1312 432 WIRE -1312 592 -1312 560 WIRE -1376 704 -1376 384 WIRE -1376 704 -1488 704 WIRE 1136 704 1136 48 WIRE 1136 704 -1376 704 FLAG -1312 592 0 FLAG -1008 -144 0 FLAG -1600 480 0 FLAG -2016 192 0 FLAG -944 192 0 FLAG -496 128 0 FLAG 160 240 0 FLAG 32 240 0 FLAG 352 256 0 FLAG 896 240 0 FLAG 816 208 0 FLAG 1152 112 0 FLAG 1136 -128 AGC1 FLAG -112 112 0 FLAG -112 -48 AGCampout FLAG 752 112 ref FLAG -1792 272 0 FLAG 624 240 0 FLAG 416 32 0 SYMBOL npn -1504 64 R0 SYMATTR InstName Q1 SYMATTR Value 2N3904 SYMBOL npn -1152 64 M0 SYMATTR InstName Q2 SYMATTR Value 2N3904 SYMBOL npn -1376 336 R0 SYMATTR InstName Q3 SYMATTR Value 2N3904 SYMBOL res -1328 464 R0 SYMATTR InstName R1 SYMATTR Value 500 SYMBOL res -1456 -144 R0 SYMATTR InstName R2 SYMATTR Value 1.5k SYMBOL res -1232 -144 R0 SYMATTR InstName R3 SYMATTR Value 1.5k SYMBOL voltage -1008 -240 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 12 SYMBOL voltage -1600 368 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value 1 SYMBOL voltage -2016 96 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value SINE(5 10m 1k) SYMBOL res -1600 96 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R4 SYMATTR Value 1k SYMBOL voltage -944 96 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V4 SYMATTR Value 5 SYMBOL res -976 96 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R5 SYMATTR Value 1k SYMBOL cap -1440 -16 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 10µ SYMBOL Opamps\\AD711 -496 -32 R0 SYMATTR InstName U1 SYMBOL res -576 0 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R6 SYMATTR Value 10k SYMBOL res -576 48 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R7 SYMATTR Value 10k SYMBOL res -544 192 R180 WINDOW 0 36 76 Left 2 WINDOW 3 36 40 Left 2 SYMATTR InstName R8 SYMATTR Value 10k SYMBOL res -448 -80 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R9 SYMATTR Value 10k SYMBOL cap -320 16 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C2 SYMATTR Value 10µ SYMBOL diode 144 32 R0 SYMATTR InstName D1 SYMATTR Value 1N4148 SYMBOL res 144 128 R0 SYMATTR InstName R10 SYMATTR Value 200 SYMBOL Opamps\\OP291 32 -32 R0 SYMATTR InstName U2 SYMBOL res 336 80 R0 SYMATTR InstName R11 SYMATTR Value 1k SYMBOL cap 336 192 R0 SYMATTR InstName C3 SYMATTR Value 10µ SYMBOL res 672 -64 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R12 SYMATTR Value 100k SYMBOL res 544 16 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R13 SYMATTR Value 1k SYMBOL Opamps\\OP291 624 -16 R0 SYMATTR InstName U3 SYMBOL Opamps\\OP291 896 -16 R0 SYMATTR InstName U4 SYMBOL res 944 -64 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R14 SYMATTR Value 10k SYMBOL res 848 16 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R15 SYMATTR Value 10k SYMBOL voltage 816 112 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V5 SYMATTR Value 2 SYMBOL res 1088 32 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R16 SYMATTR Value 1k SYMBOL cap 1136 48 R0 SYMATTR InstName C4 SYMATTR Value 10µ SYMBOL res -128 16 R0 SYMATTR InstName R17 SYMATTR Value 4.4k SYMBOL cap -1856 96 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C5 SYMATTR Value 10µ SYMBOL voltage -1792 176 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V6 SYMATTR Value 5 TEXT -960 312 Left 2 !.tran 200m TEXT 1192 32 Left 2 ;V out = Vref + (Vref - Vin) = 2Vref - Vin TEXT 1440 344 Left 2 ;AGC circuit designed for 10mv TEXT -1400 -296 Left 2 ;long tailed pair TEXT -608 -328 Left 2 ;differential amplifier TEXT -32 -328 Left 2 ;ideal diode detector TEXT 296 312 Left 2 ;averager (LPF) TEXT 480 -288 Left 2 ;Non-inverting Amplifier TEXT 864 -280 Left 2 ;inverting amplifer TEXT 1184 176 Left 2 ;AGC time setter TEXT 352 -256 Left 2 ;higher gain here means overall less voltage out TEXT -240 -144 Left 2 ;100 mv out TEXT 864 560 Left 2 ;need a quad opamp with rail to rail input/output, low voltage offset. (first opamp needs 12v supply) TEXT 96 320 Left 2 ;or 50 ohm TEXT -216 512 Left 2 ;AA1GD Aug. 18 2021