Version 4 SHEET 1 1212 1020 WIRE 640 32 464 32 WIRE 464 64 464 32 WIRE 640 80 640 32 WIRE 752 160 640 160 WIRE 848 160 752 160 WIRE 928 160 848 160 WIRE 464 176 464 144 WIRE 928 224 848 224 WIRE 528 240 528 144 WIRE 528 240 416 240 WIRE 608 240 608 144 WIRE 640 240 608 240 WIRE 752 240 752 224 WIRE 752 240 640 240 WIRE 640 256 640 240 WIRE 736 256 640 256 WIRE 848 256 848 224 WIRE 640 288 640 256 WIRE -112 304 -384 304 WIRE 112 336 32 336 WIRE 208 336 112 336 WIRE 224 336 208 336 WIRE 320 336 288 336 WIRE 336 336 320 336 WIRE 416 336 416 240 WIRE 512 336 480 336 WIRE 576 336 512 336 WIRE 512 352 512 336 WIRE -112 368 -304 368 WIRE 112 384 112 336 WIRE -304 400 -304 368 WIRE 736 400 736 256 WIRE 752 400 736 400 WIRE 864 400 816 400 WIRE 928 400 864 400 WIRE -384 416 -384 304 WIRE 416 416 416 336 WIRE 480 416 480 336 WIRE 208 448 208 336 WIRE 224 448 208 448 WIRE 320 448 320 336 WIRE 320 448 288 448 WIRE 512 448 512 416 WIRE 480 464 480 416 WIRE 864 496 864 480 WIRE 480 560 480 544 FLAG 512 448 0 FLAG -304 480 0 FLAG -384 416 0 FLAG 928 400 Audio IOPIN 928 400 Out FLAG 640 464 0 FLAG 848 256 0 FLAG 464 176 0 FLAG 864 496 0 FLAG 112 384 IF IOPIN 112 384 Out FLAG 480 560 0 SYMBOL SpecialFunctions\\modulate -112 304 R0 WINDOW 39 16 64 Left 0 WINDOW 40 16 92 Left 0 WINDOW 3 16 -20 Left 0 WINDOW 123 16 8 Left 0 SYMATTR SpiceLine mark=455k SYMATTR SpiceLine2 space=455k SYMATTR Value Rout=220 SYMATTR Value2 Vhigh={ifampl} Vlow=0 SYMATTR InstName A1 SYMBOL voltage -304 384 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName Modulation SYMATTR Value SINE(1v {moddepth} {modfreq}) SYMBOL cap 288 320 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C1241 SYMATTR Value 0.01µ SYMBOL diode 416 352 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName D1060 SYMATTR Value 1N4148 SYMBOL cap 288 432 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C1240 SYMATTR Value 1µ SYMBOL res 432 320 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R1201 SYMATTR Value 1K SYMBOL npn 576 288 R0 SYMATTR InstName Q1048 SYMATTR Value 2N3904 SYMBOL cap 496 352 R0 SYMATTR InstName C1239 SYMATTR Value 0.001µ SYMBOL res 624 368 R0 SYMATTR InstName R1199 SYMATTR Value 1K SYMBOL res 624 224 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R1200 SYMATTR Value 470k SYMBOL res 624 144 R0 SYMATTR InstName R1197 SYMATTR Value 4.2K SYMBOL res 624 64 R0 SYMATTR InstName R1198 SYMATTR Value 100 SYMBOL cap 736 160 R0 SYMATTR InstName C1236 SYMATTR Value 0.01µ SYMBOL polcap 832 160 R0 WINDOW 3 24 64 Left 0 SYMATTR Value 10µ SYMATTR InstName C1237 SYMATTR Description Capacitor SYMATTR Type cap SYMATTR SpiceLine V=16 Irms=0 Rser=2.8 MTBF=0 Lser=0 mfg="AVX" pn="TAJC106M016" type="Tantalum" ppPkg=1 SYMBOL cap 912 160 R0 SYMATTR InstName C1235 SYMATTR Value 0.01µ SYMBOL cap 816 384 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C1234 SYMATTR Value 1µ SYMBOL voltage 464 48 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value 6 SYMBOL res 848 384 R0 SYMATTR InstName Rload SYMATTR Value 10k SYMBOL res 464 448 R0 SYMATTR InstName Rbg SYMATTR Value 220k SYMBOL res 624 128 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName Rcb SYMATTR Value 470k SYMBOL schottky 416 432 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName Dmod SYMATTR Value BAT54 SYMATTR Description Diode SYMATTR Type diode TEXT -344 840 Left 0 !.fourier {modfreq} V(Audio) TEXT -344 808 Left 0 !.tran 0 60m 50m 10m TEXT -344 672 Left 0 !.options plotwinsize=0 ; compression off for lowest spice-inherent THD TEXT -392 48 Left 0 ;FT-817 AM Demodulator Simulation - Modification 2 TEXT -120 424 Left 0 ;Simulated DSB-AM \nsignal at 455kHz IF TEXT 496 592 Left 0 ;Actual devices:\nD1060 - BAS316 (similar characteristics to 1N4148, 1N914)\nQ1048 - 2SC4154E (datasheet not found) TEXT 896 496 Left 0 ;Actual Rload unknown TEXT -280 520 Left 0 ;DC Offset: \n 1V for DSB AM with carrier\n 0V for DSB AM suppressed carrier\nAmplitude(V)=%modulation/100 TEXT -344 696 Left 0 !.param moddepth=0.95 ; modulation depth 1.0 = 100% TEXT -344 864 Left 0 !;.step param moddepth list 0.30 0.95\n;.step param modfreq list 100 1000\n;.step param ifampl list 0.0625 1.0 2.0\n;.step oct param ifampl .03125 2 2\n.step param ifampl list 1.2 1.25\n;.step param Rbg list 470k 220k 100k 47k TEXT -344 776 Left 0 !.param Rbg=220k ;Added resistor from Q1048 base to gnd TEXT -344 752 Left 0 !.param ifampl=2.0 ;value for A1's Vhigh attribute TEXT -344 728 Left 0 !.param modfreq=1000 ; modulation frequency TEXT -344 88 Left 0 ;Added components:\n - Rcb 470K\n - Rbg 220K\n - Dmod BAT54 or equiv Schottky