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gEDA-user: Simple JFET Preamp Simulation

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


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