Multiple-tuned Amplifier Program Jack Porter Cubic Corporation P. O. Box 85587 San Diego, CA 92138 (619) 277-6780 Permission to publish the above information is granted. The program was developed using a TRS-80 Model 4 computer with the DOSPLUS IV operating system and Model 4 Basic, a version of Microsoft Basic which is very similar to the one used on the IBM PC. The program should run with very minor changes using any version of Microsoft Basic. The effects of any statements which are peculiar to Model 4 Basic, DOSPLUS, or the Gemini 10 printer are explained by remarks in the program at those lines. The program requires 16K of memory and a monochrome display. The display formats in the program use 80 columns and 24 lines. Abstract: This program is used to design tuned amplifier coupling networks which consist of one to eight tuned circuits each. These filter networks may be of any conventional filter type, such as Butterworth, Chebyshev or Bessel. The program calculates capacitor, inductor and resistor values, and transformer turns ratios required to form a filter network with a specified shape, center frequency, and bandwidth which will provide the desired mismatch ratios for the transistors which are coupled by it. The program also calculates low-pass prototype element values for Butterworth and Chebyshev filters. For other types of filters these must be entered from the keyboard. Variable Descriptions: Am: Chebyshev filter passband ripple in dB. Am=0 for Butterworth filters. Ap: Power gain in dB. BS, BL: Imaginary parts of source and load admittances. BW: Bandwidth in MHz. Ck: Tuning capacitance of k'th tuned circuit in pF. Ck,k+1: Coupling capacitance between tuned circuits k and k+1. Ct: Total capacitance at each node in pF. F0: Design center frequency in MHz. Fc: Corrected center frequency used in calculations. GS, GL: Real parts of source and load admittances. K: Stern stability factor. L: Tuned circuit inductance in nH. Mia, Moa: Input and output mismatch ratios for transistor a. Mib, Mob: Mismatch ratios for transistor b. MS, ML: Source and load mismatch ratios. N: Number of tuned circuits. N1, N2: Turns ratios at filter input and output. Q0: Reciprocal of filter fractional bandwidth. Q0=Fc/BW. Q1, Q2: Q's of the first and last tuned circuits in the filter. QL: Loaded Q of a single-tuned circuit. Qu: Unloaded circuit Q; approximately equal to inductor Q. r: Low-pass prototype filter termination resistance for N odd, or conductance for N even. R1, R2: Loading resistance values at filter input and output. S: Alignment sensitivity. Y11, Y21, Y12, Y22: Transistor short circuit admittance parameters. Enter these values in data statements in that order, real part of each Y parameter first. Yi, Yo: Transistor input and output admittances. Sample program run showing text which is displayed on the screen: RUN "TUNEDAMP/BAS" TUNED AMPLIFIERS 05/12/86 N, Am(dB)? 3, -1 Prototype element values 1 ? 2.2034 2 ? .97051 3 ? .33742 Prototype element values: 1 2.2034 2 .97051 3 .33742 r= 1 Print element values? Y TUNED AMPLIFIERS N= 3 Am=-1 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Coupling network types: 1. Interstage 2. Input 3. Output? 1 Transistors? 1, 2 Mia, Moa, Mib, Mob? 10, 20, 8, 12 Ka= 2.833 Sa= .64357 Kb= 5.0985 Sb= .454846 Are K and S OK? N Mia, Moa, Mib, Mob? 10, 50, 10, 20 Ka= 6.88015 Sa= .378057 Kb= 10.0663 Sb= .270341 Are K and S OK? Y TUNED AMPLIFIERS N= 3 Am=-1 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Mia= 10 Moa= 50 Mib= 10 Mob= 20 Ka= 6.88015 Sa= .378057 Kb= 10.0663 Sb= .270341 F0(MHz), BW(MHz), Qu? 180, 15, 120 Options: 1. Select C12 2. Select Ct 3. N1=1 4. N2=1? 1 C12(pF)? .5 Fc= 179.844 MHz Ap= 16.5514 dB Q1= 26.4178 Q2= 4.04552 Qu= 120 R1= 6207.32 R2= 679.082 N1= 2.53424 N2= 2.54096 L= 89.3367 nH Ct= 8.76639 pF C 1 = 7.80128 C 2 = 6.98868 C 3 = 5.48921 C 12 = .5 C 23 = 1.27771 Print results? Y New C? N New M's? N TUNED AMPLIFIERS N= 3 Am=-1 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Coupling network types: 1. Interstage 2. Input 3. Output? 0 TUNED AMPLIFIERS 05/12/86 N, Am(dB)? 2, .1 Specify: 1. Ripple BW 2. 3 dB BW? 2 Prototype element values: 1 1.6545 2 1.22071 r= .737811 Print element values? N TUNED AMPLIFIERS N= 2 Am= .1 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Coupling network types: 1. Interstage 2. Input 3. Output? 2 Transistor? 1 GS, BS, MS, Mib, Mob? .02, 0, 2, 10, 50 K= 6.88015 S= .378057 Are K and S OK? Y TUNED AMPLIFIERS N= 2 Am= .1 05/12/86 Transistor: 1. MRF904 10V 2.5mA 180 MHz MS= 2 Mib= 10 Mob= 50 K= 6.88015 S= .378057 F0(MHz), BW(MHz), Qu? 180, 15, 120 Options: 1. Select C12 2. Select Ct 3. N1=1 4. N2=1? 1 C12(pF)? .5 Fc= 179.844 MHz Ap(Transducer)=-5.13807 dB Q1= 19.8367 Q2= 19.8368 Qu= 120 R1= 12263.2 R2= 5653.23 N1= 7.86234 N2= 4.82723 L= 91.9257 nH Ct= 8.51949 pF C 1 = 8.01949 C 2 = 7.50881 C 12 = .5 Print results? Y New C? N New M's? N TUNED AMPLIFIERS N= 2 Am= .1 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Coupling network types: 1. Interstage 2. Input 3. Output? 0 TUNED AMPLIFIERS 05/12/86 N, Am(dB)? 1, 0 Prototype element values: 1 2 r= 1 Print element values? N TUNED AMPLIFIERS N= 1 Am= 0 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Coupling network types: 1. Interstage 2. Input 3. Output? 3 Transistor? 2 Mia, Moa, ML, GL, BL? 10, 20, 1, .02, 0 K= 10.0663 S= .270341 Are K and S OK? Y TUNED AMPLIFIERS N= 1 Am= 0 05/12/86 Transistor: 2. 2N4957 10V 2.0mA 180 MHz Mia= 10 Moa= 20 ML= 1 K= 10.0663 S= .270341 F0(MHz), BW(MHz), Qu? 180, 25, 120 Options: 1. Select C12 2. Select Ct 3. N1=1 4. N2=1? 3 Fc= 179.565 MHz Ap= 20.4109 dB QL= 7.18262 Qu= 120 R1= 1033.43 N1= 1 N2= 3.50168 L= 37.8275 nH Ct= 20.7677 pF C 1 = 18.8655 Print results? N New C? Y Options: 1. Select C12 2. Select Ct 3. N1=1 4. N2=1? 2 Ct(pF)? 8 Fc= 179.565 MHz Ap= 20.4109 dB QL= 7.18262 Qu= 120 R1= 2682.74 N1= 1.6112 N2= 5.6419 L= 98.1986 nH Ct= 8 pF C 1 = 7.26726 Print results? Y New C? N New M's? N TUNED AMPLIFIERS N= 1 Am= 0 05/12/86 Transistors: 1. MRF904 10V 2.5mA 180 MHz 2. 2N4957 10V 2.0mA 180 MHz Coupling network types: 1. Interstage 2. Input 3. Output? -1 Ready Printer output from sample program run: TUNED AMPLIFIERS 05/23/86 N= 3 Prototype element values: 1 2.2034 2 .97051 3 .33742 r= 1 Transistors: MRF904 10V 2.5mA 180 MHz 2N4957 10V 2.0mA 180 MHz Y11= +1.730E-03 +5.063E-03j Y11= +2.585E-03 +6.348E-03j Y21= +6.583E-02 -2.481E-02j Y21= +5.396E-02 -2.084E-02j Y12= -2.305E-05 -5.248E-04j Y12= -7.264E-08 -4.480E-04j Y22= +7.946E-05 +1.590E-03j Y22= +1.397E-04 +1.296E-03j Mia= 10 Moa= 50 Mib= 10 Mob= 20 Ka= 6.88015 Sa= .378057 Kb= 10.0663 Sb= .270341 Yia= +5.317E-03 +1.345E-02j Yib= +5.769E-03 +1.459E-02j Yoa= +8.434E-04 +3.375E-03j Yob= +4.682E-04 +2.146E-03j N= 3 F0= 180 MHz BW= 15 MHz Fc= 179.844 MHz Ap= 16.5514 dB Q1= 26.4178 Q2= 4.04552 Qu= 120 R1= 6207.32 6 R2= 679.082 6 N1= 2.53424 N2= 2.54096 L= 89.3367 nH Ct= 8.76639 pF C1= 7.80128 pF C12= .5 pF C2= 6.98868 pF C23= 1.27771 pF C3= 5.48921 pF TUNED AMPLIFIERS 05/23/86 Transistor: MRF904 10V 2.5mA 180 MHz Y11= +1.730E-03 +5.063E-03j Y21= +6.583E-02 -2.481E-02j Y12= -2.305E-05 -5.248E-04j Y22= +7.946E-05 +1.590E-03j MS= 2 Mib= 10 Mob= 50 K= 6.88015 S= .378057 GS= .02 BS= 0 Yib= +5.317E-03 +1.345E-02j Yob= +8.434E-04 +3.375E-03j N= 2 Am= .1 dB 3 dB BW F0= 180 MHz BW= 15 MHz Fc= 179.844 MHz Ap(Transducer)=-5.13807 dB Q1= 19.8367 Q2= 19.8368 Qu= 120 R1= 12263.2 6 R2= 5653.23 6 N1= 7.86234 N2= 4.82723 L= 91.9257 nH Ct= 8.51949 pF C1= 8.01949 pF C12= .5 pF C2= 7.50881 pF TUNED AMPLIFIERS 05/23/86 Transistor: 2N4957 10V 2.0mA 180 MHz Y11= +2.585E-03 +6.348E-03j Y21= +5.396E-02 -2.084E-02j Y12= -7.264E-08 -4.480E-04j Y22= +1.397E-04 +1.296E-03j Mia= 10 Moa= 20 ML= 1 K= 10.0663 S= .270341 Yia= +5.769E-03 +1.459E-02j Yoa= +4.682E-04 +2.146E-03j GL= .02 BL= 0 N= 1 Am= 0 dB F0= 180 MHz BW= 25 MHz Fc= 179.565 MHz Ap= 20.4109 dB QL= 7.18262 Qu= 120 R1= 2682.74 6 N1= 1.6112 N2= 5.6419 L= 98.1986 nH Ct= 8 pF C1= 7.26726 pF