Some experiments
AF amplifier to interface with diode product detector Circuits from EMRFD were used to make the AF amplifier with SSB filter. gnucap simulator was used to get some idea of circuit behaviour before actual construction. Here is the circuit that was simulated. Dotted lines indicate how PD is connected to AF amplifier. Files used for simulation .................. *** filename BC547B.MOD *** .MODEL BC547B NPN( + IS=2.39E-14 + NF=1.008 + ISE=3.545E-15 + NE=1.541 + BF=294.3 + IKF=0.1357 + VAF=63.2 + NR=1.004 + ISC=6.272E-14 + NC=1.243 + BR=7.946 + IKR=0.1144 + VAR=25.9 + RB=1 + IRB=1E-06 + RBM=1 + RE=0.4683 + RC=0.85 + XTB=0 + EG=1.11 + XTI=3 + CJE=1.358E-11 + VJE=0.65 + MJE=0.3279 + TF=4.391E-10 + XTF=120 + VTF=2.643 + ITF=0.7495 + PTF=0 + CJC=3.728E-12 + VJC=0.3997 + MJC=0.2955 +