{ THIS SECTION PRINTS THE TITLE AND REFERANCE INFO }
LABEL 100,200,300,400,500;

BEGIN
  CLRSCR;MF:=0.0;
  SAME_TYPE:=FALSE;   { NOT EDITING SO SET TO FALSE }
  WRITELN('                   RF NETWORK ANALYSIS PROGRAM');
  WRITELN('                      by: WILLIAM L. MUNSON');
  WRITELN('                  VERSION  1.1  -  OCT. 22 1987');
  WRITELN;
  WRITELN('NETWORK may be used for non-commercial purposes only.');
  WRITELN('No commercial use of NETWORK may be made without the');
  WRITELN('author',chr(39),'s express written permission.');WRITELN;
  WRITELN('1)  Units are ohms, nH, pF, Mhz  and inches.');
  writeln('2)  Maximum number of sections is Two Hundred.');
  writeln('3)  IL(DB)= Insertion loss in dB.');
  writeln('4)  RL(DB)= Return loss in dB.');
  writeln('5)  VSWR  = Volatage Standing Wave Ratio.');
  writeln('6)  RHO   = Reflection Coefficient.');
  writeln('7)  ZIN(R)= Real part of input impedance.');
  writeln('8)  ZIN(I)= Imag. part of input impedance.');writeln;
  WRITELN('NOTE: The load resistance can be entered as a complex number.');
  writeln;


{ THIS SECTION CHECKS FOR INPUT FROM FILE REQUEST }
BEGIN

{ THIS SECTION CLEARS ALL OF THE ARRAYS TO 0 }
       I:=1;
       REPEAT;
          R[I]:=0;
          C[I]:=0;
          L[I]:=0;
          ET[I]:=0;
          I:=I+1
       UNTIL I=201;


300: WRITE('DO YOU WANT A (N)EW OR A (S)AVED NETWORK? ');READLN(Q1);
     IF (Q1='S') OR (Q1='s') THEN
          BEGIN
          CLRSCR;
          WRITE('DO YOU WANT A DIRECTORY (Y/N)? ');READLN(FILENAME);
          WRITELN;
          IF (FILENAME='Y') OR (FILENAME='y') THEN FILES;
          WRITELN;WRITELN;WRITE('WHAT IS THE NAME OF THE FILE? ');READLN(FILENAME);
          ASSIGN(SAVEFILE,FILENAME);
          RESET(SAVEFILE);
          READLN(SAVEFILE,DATA);  {READ NUMBER OF SECTIONS}
          REMOVEBLANKS;
          VAL(DATA,NS,CODE);
          READLN(SAVEFILE,DATA);  {READ SOURCE RESISTANCE}
          REMOVEBLANKS;
          VAL(DATA,RS,CODE);
          READLN(SAVEFILE,DATA);
          REMOVEBLANKS;
          VAL(DATA,RL,CODE);
          FOR N:=1 TO NS DO
               BEGIN
               READLN(SAVEFILE,DATA);
               REMOVEBLANKS;
               VAL(DATA,ET[N],CODE);
               READLN(SAVEFILE,DATA);
               REMOVEBLANKS;
               VAL(DATA,R[N],CODE);
               READLN(SAVEFILE,DATA);
               REMOVEBLANKS;
               VAL(DATA,L[N],CODE);
               READLN(SAVEFILE,DATA);
               REMOVEBLANKS;
               VAL(DATA,C[N],CODE);
               END;

          CLOSE(SAVEFILE);
          END;


{ THIS SECTION INPUTS AND CHECKS THE NUMBER OF CIRCUIT ELEMENTS }

     IF (Q1<>'S') AND (Q1<>'s') THEN
       BEGIN
       CORRECT:=FALSE;
       REPEAT;
       WRITELN('HOW MANY SECTIONS  [MAX=200]');
       WRITE('(DONT COUNT THE LOADS)? ');READLN(NS);
       IF (NS>0) AND (NS<=200) THEN CORRECT:=TRUE
       UNTIL CORRECT;
       CORRECT:=FALSE;

       REPEAT;
       WRITELN;WRITE('ENTER THE SOURCE RESISTANCE (OHMS)? ');
       READLN(RS);IF RS>0.0 THEN CORRECT:=TRUE;
       UNTIL CORRECT;
       CORRECT:=FALSE;


{ THIS SECTION ENTERS THE COMPONENT VALUES INTO THE ARRAYS }

       N:=1;
       REPEAT;
       ENTER_ELEMENT_TYPE;
       N:=N+1;
       UNTIL N>NS;
       CLRSCR;

{ THIS SECTION ENTERS THE LOAD RESISTANCE }

500: CORRECT:=FALSE;
     BEGIN
     WRITELN('TO ENTER A COMPLEX NUMBER FOR THE LOAD VALUE.');
     WRITELN('USE THE SERIES EQUIVALENT FORM  EG.- (1.28+J12.45) or (1.28-J12.45)');
     WRITELN;
     REPEAT;
       WRITELN;WRITE('LOAD RESISTANCE (OHMS)? ');READLN(DATA);
     UNTIL LENGTH(DATA)>0;
         CORRECT:=FALSE;
         IF POS('J',DATA)>0 THEN CORRECT:=TRUE;
         IF POS('j',DATA)>0 THEN CORRECT:=TRUE;
         IF CORRECT THEN
           BEGIN
           WRITELN;WRITELN('WHAT IS THE FREQ. THAT THE COMPLEX NUMBER IS SPECIFIED AT? ');
           WRITE('FREQUENCY (Mhz)? ');
           READLN(FREQ);
           NS:=NS+1;N:=N+1;      {MAKE ROOM FOR ONE MORE SECTION }
           POSITION:=POS('+',DATA);
           IF POSITION>0 THEN
             BEGIN
             RESIST:=COPY(DATA,1,POSITION-1);
             IMAG:=COPY(DATA,POSITION+2,LENGTH(DATA)-POSITION);
             INDUCT:=TRUE;
             CALC_VALUES;
             END;
           POSITION:=POS('-',DATA);
           IF POSITION>0 THEN
             BEGIN
             RESIST:=COPY(DATA,1,POSITION-1);
             IMAG:=COPY(DATA,POSITION+2,LENGTH(DATA)-POSITION);
             INDUCT:=FALSE;
             CALC_VALUES;
             END;
           END;
{ THE NUMBER MUST NOT BE COMPLEX SO ASSUME IT IS JUST A SIMPLE VALUE }
      IF NOT CORRECT THEN
        BEGIN
           REMOVEBLANKS;  {REMOVE ALL ILLEGAL CHAR FROM THE STRING}
           VAL(DATA,RL,CODE);
           IF CODE>0 THEN GOTO 500;
        END;
     END;
  END;
{ THIS SECTION EDITS THE ELEMENT VALUES }

     WRITELN;WRITE('EDIT ELEMENTS (Y/N)? ');READLN(Q1);
200: IF (Q1='Y') OR (Q1='y') THEN
     BEGIN
     WRITELN('   ');
     PRINT_ELEMENT_TABLE;
     REPEAT;
     WRITE('ENTER (S)OURCE, (L)OAD, ELEMENT #, OR (Q) TO QUIT ? ');
     READLN(Q1);

     IF (Q1='S') OR (Q1='s') THEN
          BEGIN
          WRITE('SOURCE RESISTANCE (OHMS)? ');READLN(RS);
          PRINT_ELEMENT_TABLE;
          END;

     IF (Q1='L') OR (Q1='l') THEN
          BEGIN
           WRITE('LOAD RESISTANCE (OHMS)? ');READLN(RL);
           PRINT_ELEMENT_TABLE;
          END;

     VAL(Q1,N,CODE);
     IF (CODE=0) AND (N>0) AND (N<=NS) THEN
          BEGIN
          WRITELN;WRITE('CHANGE ELEMENT TYPE (Y/N)? ');READLN(Q1);
          IF (Q1='Y') OR (Q1='y') THEN SAME_TYPE:=FALSE ELSE SAME_TYPE:=TRUE;
          ENTER_ELEMENT_TYPE;SAME_TYPE:=FALSE;
          PRINT_ELEMENT_TABLE;
          END;

     UNTIL (Q1='Q') OR (Q1='q');
     END;

{ THIS SECTION DEFINES OR EDITS THE FREQUENCY RANGE }

     CLRSCR;
IF MF>0 THEN
     BEGIN
     WRITE('SAME FREQUENCY RANGE (Y/N)? ');READLN(Q1);
     END;


100: IF (Q1='N') OR (Q1='n') OR (MF=0.0) THEN
     BEGIN
     WRITE('START FREQUENCY (Mhz)? ');READLN(MF);
     WRITE('STEP FREQUENCY  (Mhz)? ');READLN(DF);
     WRITE('NUMBER OF STEPS      ? ');READLN(NF);NF:=NF-1;
     END;

WRITE('OUTPUT TO (S)CREEN OR (P)RINTER? ');READLN(Q1);
IF Q1='p' THEN Q1:='P';

IF Q1='P' THEN
  BEGIN
  WRITELN('ENTER A DESCRIPTION OF THE NETWORK TO BE USED AS A HEADER ON THE PRINTOUT.');
  WRITE('? ');READLN(DESCRIPTION);
  END;

CLRSCR;

{ THIS SECTION PRINTS THE HEADER INFO FOR THE SCREEN AND IF SELECTED
   FOR THE PRINTER }
WRITELN('   FREQ(Mhz)    IL(DB)     RL(DB)       VSWR        RHO      ZIN(R)    ZIN(I)');


IF Q1='P' THEN
     BEGIN
     WRITELN(LST,'                    =================================== ');
     WRITELN(LST,'                    RF NETWORK ANALYSIS PROGRAM VER 1.1');
     WRITELN(LST,'                    ===================================');
     WRITELN(LST,'');WRITELN(LST,DESCRIPTION);WRITELN(LST,'');
     WRITELN(LST,'NETWORK LISTING.');WRITELN(LST,'');
     WRITELN(LST,'ELEM  TYPE  DESCRIPTION                      R             L             C');
     WRITELN(LST,'                                           (ZO)           (L)           (E)');
     WRITELN(LST,'SOURCE R                           ',RS:14:3);
     N:=1;REPEAT;
     WRITE(LST,N:2,ET[N]:7,'   ');
     PRINT_TYPE;
     WRITELN(LST,R[N]:14:3,L[N]:14:3,C[N]:14:3);
     N:=N+1;
     UNTIL N>NS;
     WRITELN(LST,'LOAD R                             ',RL:14:3);
     WRITELN(LST,'');WRITELN(LST,'NOTE:   R,L,C ARE FOR ELEMENT TYPES 1-11.');
     WRITELN(LST,'        ZO,L,E ARE FOR ELEMENT TYPES 12-16.');WRITELN(LST,'');
     WRITELN(LST,'   FREQ(Mhz)    IL(DB)     RL(DB)       VSWR        RHO      ZIN(R)    ZIN(I)');

     END;


{ THIS SECTION SETS UP THE LOOPS WHICH CALCULATE THE GAIN AND IMPEDANCE OF
   THE NETWORK.}

     CO:=MF+DF*NF*FR;K:=0.0;
     WHILE K<=NF  DO  (* THIS IS THE START OF THE 'K' LOOP WHICH ENDS WHEN K>NF *)
     BEGIN
     F:=(MF+K*DF)*FR;W:=2.0*PI*F;
     A1:=1.0;D1:=1.0;A4:=0.0;B1:=0.0;B4:=0.0;C1:=0.0;C4:=0.0;D4:=0.0;
          N:=1;
          WHILE N<=NS  DO  { THIS IS THE START OF THE 'N' LOOP WHICH ENDS WHEN N>NS }
          BEGIN
          IF ET[N]=1 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=R[N];IB:=0.0;RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=2 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;RC:=1.0/R[N];IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=3 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=W*L[N]*LC;RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=4 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;RC:=0.0;IC:=-1.0/(W*L[N]*LC);RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=5 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=-1/(W*C[N]*CC);RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=6 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;RC:=0.0;IC:=W*C[N]*CC;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=7 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=R[N];IB:=W*L[N]*LC-1/(W*C[N]*CC);
               RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=8 THEN
               BEGIN
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;V4:=SQR(W)*L[N]*LC*C[N]*CC-1;
               RC:=W*W*SQR(C[N]*CC)*R[N]/(W*W*SQR(C[N]*CC)*SQR(R[N])+SQR(W*W*L[N]*LC*C[N]*CC-1));
               IC:=-W*C[N]*CC*V4/(SQR(W)*SQR(C[N]*CC)*SQR(R[N])+SQR(V4));
               RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=9 THEN
               BEGIN
               RB:=SQR(W)*R[N]*SQR(L[N]*LC)/(W*W*SQR(L[N]*LC)+SQR(R[N])*SQR(1-W*W*L[N]*LC*C[N]*CC));
               RA:=1.0;IA:=0.0;T:=W*W*SQR(L[N]*LC)+SQR(R[N])*SQR(1-W*W*L[N]*LC*C[N]*CC);
               IB:=W*L[N]*LC*R[N]*R[N]*(1-W*W*L[N]*LC*C[N]*CC)/T;RC:=0.0;IC:=0.0;RD:=1;ID:=0.0;
               END;

          IF ET[N]=10 THEN
               BEGIN
               RC:=1/R[N];IC:=(-1+W*W*L[N]*LC*C[N]*CC)/(W*L[N]*LC);
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=11 THEN
               BEGIN
               RB:=R[N]/(SQR(1-W*W*L[N]*LC*C[N]*CC)+SQR(W*C[N]*CC*R[N]));
               IB:=W*(L[N]*LC*(1-W*W*L[N]*LC*C[N]*CC)-C[N]*CC*SQR(R[N]))*RB/R[N];
               RA:=1.0;IA:=0.0;RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=12 THEN
               BEGIN
               V3:=W*L[N]*CM*EXPON(C[N],0.5)/3.0E+10;RA:=COS(V3);IA:=0.0;RB:=0.0;IB:=R[N]*SIN(V3);
               RC:=0.0;IC:=SIN(V3)/R[N];RD:=COS(V3);ID:=0.0;
               END;

          IF ET[N]=13 THEN
               BEGIN
               V3:=W*L[N]*CM*EXPON(C[N],0.5)/3.0E+10;
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;RC:=0.0;IC:=TAN(V3)/R[N];RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=14 THEN
               BEGIN
               V3:=W*L[N]*CM*EXPON(C[N],0.5)/3.0E+10;
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=0.0;RC:=0.0;IC:=-1/(TAN(V3)*R[N]);RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=15 THEN
               BEGIN
               V3:=W*L[N]*CM*EXPON(C[N],0.5)/3.0E+10;
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=-R[N]/TAN(V3);RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=16 THEN
               BEGIN
               V3:=W*L[N]*CM*EXPON(C[N],0.5)/3.0E+10;
               RA:=1.0;IA:=0.0;RB:=0.0;IB:=R[N]*TAN(V3);RC:=0.0;IC:=0.0;RD:=1.0;ID:=0.0;
               END;

          IF ET[N]=17 THEN
               BEGIN
               RA:=TR;IA:=0.0;RB:=0.0;IB:=0.0;RC:=0.0;IC:=0.0;RD:=1/TR;ID:=0.0;
               END;

{ THIS SECTION MULTIPLIES THE ABCD MATRICIES TOGETHER }

          A3:=A1*RA-A4*IA+B1*RC-B4*IC;A6:=A1*IA+A4*RA+B1*IC+B4*RC;
          B3:=A1*RB-A4*IB+B1*RD-B4*ID;B6:=A1*IB+A4*RB+B1*ID+B4*RD;
          C3:=C1*RA-C4*IA+D1*RC-D4*IC;C6:=C1*IA+C4*RA+D1*IC+D4*RC;
          D3:=C1*RB-C4*IB+D1*RD-D4*ID;D6:=C1*IB+C4*RB+D4*RD+D1*ID;
          A1:=A3;A4:=A6;B1:=B3;B4:=B6;C1:=C3;C4:=C6;D1:=D3;D4:=D6;
          N:=N+1;

          END;  { END OF 'N' LOOP }

{ THIS SECTION CALCULATES THE OUTPUT DATA }

          G:=(A3*RL+B3+C3*RS*RL+D3*RS)/RL; H:=(A6*RL+B6+C6*RS*RL+D6*RS)/RL;
          II:=SQRT(SQR(G)+SQR(H));
          NU[2]:=INT(-10*LN(RL*SQR(II)/(4*RS))/LN(10.0)*100.0+0.5)/100.0;
          V1:=C3*RL+D3; V2:=C6*RL+D6; Q:=SQR(V1)+SQR(V2);
          NU[6]:=INT(((A3*RL+B3)*V1+(A6*RL+B6)*V2)/Q*100.0+0.5)/100.0;
          NU[7]:=INT(((A6*RL+B6)*V1-(A3*RL+B3)*V2)/Q*100.0+0.5)/100.0;
          NU[1]:=INT(F*1000.0/(1.0E+6)+0.5)/1000.0;
          R1:=SQRT(SQR(NU[6]-RS)+SQR(NU[7]));
          R2:=SQRT(SQR(NU[6]+RS)+SQR(NU[7])); RO:=R1/R2;
          IF RO=1.0 THEN RO:=0.999999;
          NU[5]:=INT(RO*100.0+0.5)/100.0;
          NU[3]:=-INT(20.0*LN(1/RO)/LN(10.0)*100.0+0.5)/100.0;
          NU[4]:=INT((1.0+RO)/(1-RO)*100.0+0.5)/100.0;
          I:=1;
          REPEAT;
               WRITE(NU[I]:11:2);
               IF Q1='P' THEN WRITE(LST,NU[I]:11:2);
               I:=I+1;
          UNTIL I>7;
          WRITELN;
          IF Q1='P' THEN WRITELN(LST,'');
          K:=K+1.0;
     END;

{ THIS SECTION HANDLES THE OPTIONS MENU SELECTIONS }

     WRITELN;
     IF Q1='P' THEN WRITELN(LST,CHR(12));
400: REPEAT;
     WRITE('(1)CHANGE FREQ (2)EDIT ELEMENTS (3)START OVER (4)QUIT OR (5)SAVE ? ');
{$I-}
     READLN(A);
     UNTIL (A>0) AND (A<6) AND (IORESULT=0);
{$I+}
     CLRSCR;
     IF A=1 THEN
       BEGIN
       Q1:='N';
       GOTO 100;
       END;
     IF A=2 THEN
       BEGIN
       (*CLRSCR;*)
       Q1:='Y';
       GOTO 200;
       END;
     IF A=3 THEN GOTO 300;
     IF A=5 THEN
          BEGIN
          WRITE('WHAT NAME TO SAVE THE NETWORK UNDER ? ');READLN(FILENAME);;
          ASSIGN(SAVEFILE,FILENAME);
          REWRITE(SAVEFILE);
          STR(NS,DATA);
          WRITELN(SAVEFILE,DATA);  {WRITE NUMBER OS SECTIONS TO FILE}
          STR(RS,DATA);
          WRITELN(SAVEFILE,DATA);  {WRITE SOURCE RESISTANCE TO FILE}
          STR(RL,DATA);
          WRITELN(SAVEFILE,DATA);  {WRITE LOAD RESISTANCE TO FILE}
          FOR N:= 1 TO NS  DO
               BEGIN
               STR(ET[N],DATA);
               WRITELN(SAVEFILE,DATA);  {WRITE ELEM TYPE TO FILE}
               STR(R[N],DATA);
               WRITELN(SAVEFILE,DATA);  {WRITE R VALUE TO FILE}
               STR(L[N],DATA);
               WRITELN(SAVEFILE,DATA);  {WRITE L VALUE TO FILE}
               STR(C[N],DATA);
               WRITELN(SAVEFILE,DATA);  {WRITE C VALUE TO FILE}
               END;
            CLOSE(SAVEFILE);
          GOTO 400;
          END;
          END;

END.