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HAM Radio 1
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reflecto.bas
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BASIC Source File
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1979-12-31
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2KB
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75 lines
10 REM REFLECTOR ANTENNA DESIGN
20 REM "ANTENNA DESIGN USING PERSONAL COMPUTERS"
30 KEY OFF
40 CLS
50 COLOR 1,0
60 PRINT "REFLECTOR ANTENNA DESIGN"
70 COLOR 4,0
80 PI=3.141593
90 DEF FNLOG10(X)=.4343*LOG(X)
100 PRINT
110 INPUT "WHAT IS THE DISH DIAMETER(meters)";D
120 INPUT "WHAT IS THE f/d RATIO";FOD
130 INPUT "WHAT IS THE FREQUENCY(MHz)";FMC
140 XL=300/FMC
150 PRINT "HOW DO YOU WISH TO SPECIFY THE FEED POWER PATTERN:"
160 PRINT " 1- COS(TH)**N (N EVEN)"
170 PRINT " 2- 3 dB BEAMWIDTH"
180 PRINT " 3- 10 dB BEAMWIDTH"
190 INPUT IOP
200 IF IOP<1 OR IOP>3 THEN GOTO 150
210 IF IOP>1 THEN GOTO 260
220 INPUT "WHAT IS THE VALUE OF N (2,4,6,8)";N
230 IF N<>2 AND N<>4 AND N<>6 AND N<>8 THEN GOTO 220
240 COLOR 14,0
250 GOTO 370
260 IF IOP>2 THEN GOTO 300
270 INPUT "WHAT IS THE 3-dB BEAMWIDTH(degrees)";BW
280 N=-.693/LOG(COS(BW*PI/360))
290 GOTO 320
300 INPUT "WHAT IS THE 10-dB BEAMWIDTH(degrees)";BW
310 N=-2.3/LOG(COS(BW*PI/360))
320 N=2*INT(N/2)
330 IF N<2 THEN N=2
340 IF N>8 THEN N=8
350 COLOR 14,0
360 PRINT USING "WILL USE N=#";N
370 REM COMPUT APERTURE EFFICIENCY
380 F=FOD*D
390 Z0=F-D*D/(16*F)
400 TH=ATN(D/(2*Z0))
410 CTH=COS(TH)
420 STH=SIN(TH)
430 CTH2=COS(TH/2)
440 STH2=SIN(TH/2)
450 COT2=CTH2/STH2
460 LCT=LOG(CTH2)
470 STH22=STH2*STH2
480 COT22=COT2*COT2
490 MCT=(1-CTH)^3/3
500 NCT=(1-CTH^4)/4
510 EAP=18*(NCT-2*LCT-MCT-.5*STH*STH)^2*COT22
520 IF N=6 THEN EAP=14*(2*LCT+MCT+.5*STH*STH)^2*COT22
530 IF N=4 THEN EAP=40*(STH22*STH22+LCT)^2*COT22
540 IF N=2 THEN EAP=24*(STH22+LCT)^2*COT22
550 REM COMPUTE SPILLOVER EFFICIENCY: TAPER EFFICIENCY
560 ES=1-CTH^(N+1)
570 ET=EAP/ES
580 REM COMPUTE DIRECTIVITY
590 D=(PI*D/XL)^2*EAP
600 DDB=10*FNLOG10(D)
610 BW=SQR(33700!/D)
620 PRINT
630 PRINT USING "SPILLOVER EFFICIENCY= #.###";ES
640 PRINT USING "TAPER EFFICIENCY= #.###";ET
650 PRINT USING "APERTURE EFFICIENCY= #.###";EAP
660 PRINT USING "DIRECTIVITY= ######.# OR ##.# dB";D,DDB
670 PRINT USING "3 dB BEAMWIDTH= ##.## degrees";BW
680 PRINT
690 COLOR 4,0
700 INPUT "CONTINUE(Y,N)";K$
710 IF K$<>"N" THEN GOTO 40
720 COLOR 7,0
730 KEY ON
740 END