1 REM Aktive Filter
2 REM Ruediger Maurer 01.10.82
10 PI=3.14
100 CLS:PRINT"Aktive Filter 3 Ordnung":PRINT
110 PRINT"Tiefpass Mehrfach-Gegenkopplung = TG"
120 PRINT"Tiefpass Einfach -Mittkopplung = TM"
130 PRINT"Hochpass Mehrfach-Gegenkopplung = HG"
140 INPUT"Hochpass Einfach -Mittkopplung = HM";A$
150 IFA$<>"TG"ANDA$<>"TM"ANDA$<>"HG"ANDA$<>"HM"GOTO100
160 IFA$="TG"THENP=1
170 IFA$="TM"THENP=2
180 IFA$="HG"THENP=3
190 IFA$="HM"THENP=4
200 CLS
210 ONPGOSUB15000,16000,17000,18000
220 PRINT:PRINT"Filtertyp:"
230 PRINT"Bessel .......................... 1"
240 PRINT"Butterworth ..................... 2"
250 PRINT"Tschebyscheff 0.5 dB ............ 3"
260 PRINT"Tschebyscheff 1.0 dB ............ 4"
270 PRINT"Tschebyscheff 2.0 dB ............ 5"
280 INPUT"Tschebyscheff 3.0 dB ............ 6";FT
290 IFFT<1ORFT>6GOTO220
300 :
310 PRINT:INPUT"3-dB Eckfrequenz (Hz) ";FC
315 FC=2*PI*FC
320 IFFC<=0GOTO310
330 INPUT"C1 (Farad) ";C1:C=C1:PRINT
340 IFA$="HG"THENC=(C/2)
350 IFC<=0GOTO200
500 ONFTGOTO2000,3000,4000,5000,6000,7000
1999 REM * BESSEL *
2000 IFLEFT$(A$,1)="H"GOTO2200
2010 IFRIGHT$(A$,1)="G"THENFK=2.3186:Z=1:GOTO2500
2020 IFRIGHT$(A$,1)="M"THENFK=0.9914:Z=2:GOTO2500
2200 IFRIGHT$(A$,1)="G"THENFK=0.2156:Z=3
2210 IFRIGHT$(A$,1)="M"THENFK=1.0087:Z=4
2500 K1=1.7556:K2=1.2329:K3=0.3608
2700 ONZGOSUB10000,11000,12000,13000
2800 GOTO20000
2999 REM * BUTTERWORTH *
3000 IFLEFT$(A$,1)="H"GOTO3200
3010 IFRIGHT$(A$,1)="G"THENFK=2.5747:Z=1:GOTO3500
3020 IFRIGHT$(A$,1)="M"THENFK=1.3926:Z=2:GOTO3500
3200 IFRIGHT$(A$,1)="G"THENFK=0.1942:Z=3
3210 IFRIGHT$(A$,1)="M"THENFK=0.7181:Z=4
3500 K1=2:K2=2:K3=1
3700 ONZGOSUB10000,11000,12000,13000
3800 GOTO20000
3999 REM TSCHEBYSCHEFF 0.5 dB *
4000 IFLEFT$(A$,1)="H"GOTO4200
4010 IFRIGHT$(A$,1)="G"THENFK=4.0535:Z=1:GOTO4500
4020 IFRIGHT$(A$,1)="M"THENFK=2.2368:Z=2:GOTO4500
4200 IFRIGHT$(A$,1)="G"THENFK=0.1233:Z=3
4210 IFRIGHT$(A$,1)="M"THENFK=0.4471:Z=4
4500 K1=2.5038:K2=2.3862 :K3=2.2235
4700 ONZGOSUB10000,11000,12000,13000
4800 GOTO20000
4999 REM TSCHEBYSCHEFF 1.0 dB *
5000 IFLEFT$(A$,1)="H"GOTO5200
5010 IFRIGHT$(A$,1)="G"THENFK=4.7061:Z=1:GOTO5500
5020 IFRIGHT$(A$,1)="M"THENFK=2.5669:Z=2:GOTO5500
5200 IFRIGHT$(A$,1)="G"THENFK=0.1062:Z=3
5210 IFRIGHT$(A$,1)="M"THENFK=0.3896:Z=4
5500 K1=2.7598:K2=2.4114 :K3=2.6713
5700 ONZGOSUB10000,11000,12000,13000
5800 GOTO20000
5999 REM TSCHEBYSCHEFF 2.0 dB *
6000 IFLEFT$(A$,1)="H"GOTO6200
6010 IFRIGHT$(A$,1)="G"THENFK=5.8147:Z=1:GOTO6500
6020 IFRIGHT$(A$,1)="M"THENFK=3.1126:Z=2:GOTO6500
6200 IFRIGHT$(A$,1)="G"THENFK=0.0860:Z=3
6210 IFRIGHT$(A$,1)="M"THENFK=0.3213:Z=4
6500 K1=3.2294:K2=2.4073 :K3=3.3694
6700 ONZGOSUB10000,11000,12000,13000
6800 GOTO20000
6999 REM TSCHEBYSCHEFF 3.0 dB *
7000 IFLEFT$(A$,1)="H"GOTO7200
7010 IFRIGHT$(A$,1)="G"THENFK=6.8775:Z=1:GOTO7500
7020 IFRIGHT$(A$,1)="M"THENFK=3.6296:Z=2:GOTO7500
7200 IFRIGHT$(A$,1)="G"THENFK=0.0727:Z=3
7210 IFRIGHT$(A$,1)="M"THENFK=0.2755:Z=4
7500 K1=3.7055:K2=2.3844 :K3=3.9937
7700 ONZGOSUB10000,11000,12000,13000
7800 GOTO20000
9999 REM * BERECHNUNG TG *
10000 R=FK/(FC*C1):R1=R:R2=R:R3=2*R:R4=2*R
10100 C2=(6*K3*C1)/(FK*FK*(2*K1-FK))
10200 C3=C1*((2*K1-FK)/(12*FK))
10500 RETURN
10999 REM * BERECHNUNG TM *
11000 R=FK/(FC*C1):R1=R:R2=R:R3=R
11100 C2=(C1*3*K3)/(FK*FK*(K1-FK))
11200 C3=C1*(K1-FK)/(3*FK)
11500 RETURN
11999 REM * RERECHNUNG HG *
12000 R1=FK/(FC*C):C1=2*C:C2=2*C:C3=C:C4=C
12100 R2=(4*K1*FK-1)/(48*F3*FK*FK*FC*C)
12200 R3=(12*FK)/((4*K1*FK-1)*FC*C)
12500 RETURN