Hi, I can't get a simulation of this circuit to run:
http://207.192.69.113/~miallen/JFET_Preamp_1.pdf I copied this from about half-way down this page: http://www.ciphersbyritter.com/RADELECT/PREJFET/JFETPRE.HTM With GNU-Cap the Q1 drain values are pinned at 4V. With ngspice, the Q1 drain, Q2 collector and output all look the same: http://207.192.69.113/~miallen/JFET_Preamp_1.png Here's my netlist: * /usr/bin/gnetlist -v -g spice-sdb -o JFET_Preamp_1.ckt JFET_Preamp_1.sch ********************************************************* * Spice file generated by gnetlist * * spice-sdb version 4.28.2007 by SDB -- * * provides advanced spice netlisting capability. * * Documentation at http://www.brorson.com/gEDA/SPICE/ * ********************************************************* *============== Begin SPICE netlist of main design ============ V2 2 0 DC 4V R5 1 output 5K Q3 2 q2c output 2N2222A .MODEL 2N2222A NPN (IS=3.0611E-14 NF=1.00124 BF=220 IKF=0.52 VAF=104 ISE=7.5E-15 NE=1.41 NR=1.005 BR=4 IKR=0.24 VAR=28 ISC=1.06525E-11 NC=1.3728 RB=0.13 RE=0.22 RC=0.12 CJC=9.12E-12 MJC=0.3508 VJC=0.4089 CJE=27.01E-12 TF=0.325E-9 TR=100E-9) R4 0 3 40 Q2 q2c q1d 2 2N5087 .MODEL 2N5087 PNP (Is=6.734f Xti=3 Eg=1.11 Vaf=45.7 Bf=254.1 Ne=1.741 Ise=6.734f Ikf=.1962 Xtb=1.5 Br=2.683 Nc=2 Isc=0 Ikr=0 Rc=1.67 Cjc=6.2p Mjc=.301 Vjc=.75 Fc=.5 Cje=7.5p Mje=.2861 Vje=.75 Tr=10.1n Tf=467.8p Itf=.17 Vtf=5 Xtf=8 Rb=10) R3 3 output 2K JQ1 q1d input 1 2N5484 .MODEL 2N5484 NJF (VTO = -1.2796E+000 BETA = 1.71347E-003 LAMBDA = 1.93292E-002 RD = 4.41873E+000 RS = 4.41873E+000 IS = 1.25479E-016 CGS = 2.25000E-012 CGD = 2.34000E-012 PB = 1.14141E+000 FC = 5.00000E-001) R2 q1d 2 5K R1 0 input 10000K C1 1 3 200uF Vsin input 0 dc 0 ac 1 .end Can someone give me a tip on how to get this to work? Are my models bad? Do I have to do anything special to get the JFET to work? Any help would be appreciated. Mike _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
