10 REM ELLIPBP.BAS
20 REM WRITTEN BY RUSS KINCAID, AUGUST 1997. BASED ON INFO FROM
30 REM "SIMPLIFIED MODERN FILTER DESIGN" BY PHILLIP GEFFE (RIDER 1963)
40 CLS:PRINT"ELLIPTIC FUNCTION FILTERS DESIGNED FROM TABLES"
44 PRINT"THE BANDPASS DESIGNED HERE HAS A FLOATING NODE WHICH IS SUSEPTABLE"
46 PRINT"TO STRAY CAPACITANCE.  THE IMPROVED DESIGN HAS AN EXTRA INDUCTOR"
48 PRINT
50 PRINT"FOR LOWPASS ENTER (1) FOR BANDPASS ENTER (2)":INPUT TYPE
55 PRINT:INPUT"WHAT WILL YOU CALL THIS DESIGN ";NME$
60 PRINT:PRINT"CAPACITOR INPUT CONFIGURATION IS ASSUMED"
70 PI=3.1415927#
80 DIM C(11),L(11),CC(11),LL(11)
90 INPUT"SOURCE RESISTANCE:";RS
100 INPUT"LOAD RESISTANCE:";RL
110 IF TYPE = 1 THEN 160
120 INPUT"BANDEDGE FREQUENCIES (F1,F2) (HZ) ";F1,F2
130 BW=F2-F1:F0=(F1*F2)^.5 : W=2*PI*F0   :Q=F0/BW
140 PRINT:PRINT"CENTER FREQUENCY IS : ";F0
150 GOTO 180
160 INPUT"UPPER BANDEDGE FREQUENCY(HZ) : ";FU
170 BW=FU
180 PRINT"ENTER THE NORMALIZED PROTOTYPE VALUES FROM TABLES.
190 PRINT"TO END THE INPUT CYCLE, ENTER ZERO OR JUST PRESS ENTER"
200 FOR J=1 TO 9
210 PRINT"INPUT C(";J;"):";:INPUT C(J)
220 IF C(J)=0 THEN PRINT" THIS WILL END THE FILTER":GOTO 262
230 IF INT(J/2)>
     Source: geocities.com/russlk/filters
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