• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Vacuum Tube SPICE Models

Koonw

Member
2013-04-09 9:37 pm
Gu81/ГУ81 pentode model for sharing:


Code:
**** GU81 ******************************************
* Created on 02/17/2022 20:50 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: GU81.jpg
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT GU81 P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT GU81 P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=3.222 KG1=2317.17 KP=56.18 KVB=12.01 VCT=-0.1625 EX=1.31 KG2=4863.69 KNEE=215.9 KVC=2.076
+ KLAM=3.052E-14 KLAMG=2.803E-5 KNEE2=65.37 KNEX=166.47  KNK=3.763E-8 KNG=0.02817 KNPL=4.092E-9 KNSL=31537.46 KNPR=10600.24 KNSR=16388.67
+ CCG=32P CGP=0.1P CCP=26P VGOFF=-0.6 IGA=0.001 IGB=0.465 IGC=1.68 IGEX=1.84
* Vp_MAX=3200 Ip_MAX=1600 Vg_step=80 Vg_start=80 Vg_count=17
* X_MIN=73 Y_MIN=24 X_SIZE=776 Y_SIZE=633 FSZ_X=1296 FSZ_Y=736 XYGrid=false
* Rp=1400 Vg_ac=20 P_max=450 Vg_qui=-560 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=500 gridLevel2=y addKink=y isTanhKnee=y advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

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Reactions: 1 user
Does anyone happen to know if there are any pentode models that model the suppressor grid as an independent control grid? It is not commonly done in the real world and I don't know if there would be any reason to do it in an audio circuit. But I am interested in modeling a signal generator from the 1940's where the screen was used as a plate for the oscillator circuit and the suppressor is used as a control grid between the screen and plate to modulate the plate signal. Cheap radios from the same era did something similar in order to use a pentode in place of a more expensive pentagrid converter. Has anyone ever published spice models for tubes with three or more independent grids?

So far searches have turned up no golden needles in a very large haystack of suppressor grid references that tell me to connect it to the cathode!

Thanks,

Ken
 
Last edited:

Koonw

Member
2013-04-09 9:37 pm

6J32P 6Ж32П model

Code:
**** 6J32P1 ******************************************
* Created on 02/26/2022 21:08 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: 6j32p1.png
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT 6J32P P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT 6J32P1 P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=37.08 KG1=3263.2 KP=222.05 KVB=88.53 VCT=0.335 EX=1.396 KG2=2468.32 KNEE=6.145 KVC=1.811
+ KLAM=9.53E-11 KLAMG=1.624E-4   KNK=-1.77E-4 KNG=7.813E-4 KNPL=16.96 KNSL=4616.62 KNPR=3540 KNSR=2674
+ CCG=4.3P CGP=0.6P CCP=5.1P VGOFF=-0.6 IGA=0.001 IGB=0.3 IGC=8 IGEX=2
* Vp_MAX=360 Ip_MAX=7 Vg_step=1 Vg_start=-0.5 Vg_count=10
* X_MIN=39 Y_MIN=75 X_SIZE=742 Y_SIZE=578 FSZ_X=1296 FSZ_Y=736 XYGrid=false
* Rp=1400 Vg_ac=20 P_max=1 Vg_qui=-5 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=140 gridLevel2=y addKink=y isTanhKnee=n advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN(V(P,K)/KNEE)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN(V(P,K)/KNEE))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

Attachments

  • 6J32P paint-1.png
    6J32P paint-1.png
    1 MB · Views: 43

Koonw

Member
2013-04-09 9:37 pm

EF86 (Philips) model:

Code:
**** EF86_PL ******************************************
* Created on 02/26/2022 21:26 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: ef86_pl.png
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT EF86_PL  P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT EF86_PL P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=40.7 KG1=2418.21 KP=250.28 KVB=310.76 VCT=0.4522 EX=1.327 KG2=6770.18 KNEE=15.01 KVC=2.753
+ KLAM=4.883E-13 KLAMG=1.146E-4 KNEE2=6.715 KNEX=24.2  KNK=3.906E-4 KNG=1.163E-4 KNPL=0.1016 KNSL=25.3 KNPR=9.15 KNSR=1593.19
+ CCG=4.3P CGP=0.6P CCP=5.1P VGOFF=-0.6 IGA=0.001 IGB=0.3 IGC=8 IGEX=2
* Vp_MAX=500 Ip_MAX=8 Vg_step=1 Vg_start=0 Vg_count=11
* X_MIN=61 Y_MIN=63 X_SIZE=634 Y_SIZE=506 FSZ_X=1296 FSZ_Y=736 XYGrid=false
* Rp=1400 Vg_ac=20 P_max=1 Vg_qui=-5 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=140 gridLevel2=y addKink=y isTanhKnee=y advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

Attachments

  • EF86_PL paint-1.png
    EF86_PL paint-1.png
    470.4 KB · Views: 53
  • Transfer Curve EF86 6J32P.png
    Transfer Curve EF86 6J32P.png
    40.8 KB · Views: 62
Hi all
Please note my latest model, which is a Sylvania 6BN4A. As usual, it is based on the most representative sample out of 10 burnt-in tubes.

One thing to mention: Typically, the higher the Mu, the less good a triode performs at very low anode voltages. But the 6BN4A with a Mu > 40 seems to be an exception, running well with a Supply of 60V only. So, this tube is a good choice for LoV projects.

all the best, Adrian
Code:
*6BN4A LTspice model based on the generic triode model from Adrian Immler, version i5
*Note that the 6BN4 has in average a 15% smaller gm.
*A version log is at the end of this file
*100h BurnIn of 10 Sylvania tubes, sample selection and measurements done in Febr 2022
*Params fitted to the measured values by Adrian Immler, Febr 2022
*The high fit quality is presented at adrianimmler.simplesite.com
*History's best of tube describing art (plus some new ideas) is merged to this new approach.
*@ neg. Vg, Ia accuracy is similar to Koren models, and unrivaled for remote cutoff triodes
*@ small neg. Vg, the "Anlauf" current is considered.
*@ pos. Vg, Ig and Ia accuracy is on a unrivaled level (including neg. Va range!)
*This offers new simulation possibilities like grid resistor bias, backward plate modulated stages,
*Audion radio circuits, low voltage amps, guitar distortion stages or pulsed stages.
*             SY = electrode construction used by Sylvania
*             |    anode (plate)
*             |    | grid
*             |    | | cathode
*             |    | | |
.subckt 6BN4A.SYi5 A G K
+ params:
*Parameters for space charge current Is (100% assigned to Ia @ Vg < 0)
+ mu   = 53.5  ;Determines the voltage gain @ constant Ia
+ rad  = 4k05  ;Differential anode resistance, set @ Iad and Vg=0V
+ Vct  = 0.7   ;Offsets the Ia-traces on the Va axis. Electrode material's contact potential
+ kp   = 176   ;Mimics the island effect
+ xs   = 1.55  ;Determines the curve of the Ia traces. Typically between 1.2 and 1.8
+ kIsr = 64m   ;Va-independent part of the Is reduction when grid current occurs
+ kvdg  = 97   ;Va-dependent part of the Is reduction when grid current occurs
*
*Parameters for assigning the space charge current to Ia and Ig @ Vg > 0
+ kB   = 0.4   ;Describes how fast Ia drops to zero when Va approaches zero.
+ radl = 400   ;Differential resistance for the Ia emission limit @ very small Va and Vg > 0
+ tsh  = 7     ;Ia transmission sharpness from 1st to 2nd Ia area. Keep between 3 and 20. Start with 20.
+ xl   = 1.3   ;Exponent for the emission limit
*
*Parameters of the grid-cathode vacuum diode
+ kg = 550     ;Inverse scaling factor for the Va independent part of Ig (caution - interacts with xg!)
+ Vctg = 0.25  ;Offsets the log Ig-traces on the Vg axis. Electrode material's contact potential
+ xg   = 1.3   ;Determines the curve of the Ig slope versus (positive) Vg and Va >> 0
+ VT   = 0.12  ;Log(Ig) slope @ Vg<0. VT=k/q*Tk (cathodes absolute temp, typically 1150K)
+ rTr  = 0.6   ;ratio of VT for Igr. Typically 0.8
+ kVT  = 20m   ;Va dependant koeff. of VT
+ gft1 = 0.09  ;reduces the steering voltage around Vg=-Vg0, for finetuning purposes
+ gft1a= 0.4   ;reduces the steering voltage around Vg=-Vg0. Effect decreases with 1/(1+kB*Va)
+ gft2 = 1.5   ;finetunes the Igr drop @ increasing Va and around Vg=-Vg0
*
*Parameters for the caps
+ cag  = 1p2   ;From Tung-Sol datasheet
+ cak  = 1p4   ;From Tung-Sol datasheet
+ cgk  = 3p2   ;From Tung-Sol datasheet
*
*special purpose parameters
+ os = 1       ;Overall scaling factor, if a user wishes to simulate manufacturing tolerances
+ murc = 10    ;Mu of the remote cutoff triode
+ ksrc = 10G   ;Inverse Iarc gain factor for the remote cutoff triode
+ kprc = 1k    ;Mimics the island effect for the remote cutoff triode
+ Vbatt = 0    ;heater battery voltage for direct heated battery triodes
+ Vdrmax = 100 ;max voltage of internal Vg drop, for convergence improvements
*
*Calculated parameters
+ Iad = {100/rad} ;Ia where the anode a.c. resistance is set according to rad.
+ ks = {pow(mu/(rad*xs*Iad**(1-1/xs)),-xs)} ;Reduces the unwished xs influence to the Ia slope
+ ksnom = {pow(mu/(rad*1.5*Iad**(1-1/1.5)),-1.5)} ;Sub-equation for calculating Vg0
+ Vg0 = {Vct + (Iad*ks)**(1/xs) - (Iad*ksnom)**(2/3)} ;Reduces the xs influence to Vct.
+ kl = {pow(1/(radl*xl*Ild**(1-1/xl)),-xl)} ;Reduces the xl influence to the Ia slope @ small Va
+ Ild = {sqrt(radl)*1m} ;Current where the Il a.c. resistance is set according to radl.
*
*Space charge current model
Rak A K 100G ;avoids "floating net" errors
Bft   ft 0 V=1/(1+pow(2*abs(v(G,Ki)+Vg0),3)) ;an auxiliary voltage to finetune the triode around Vg=-Vg0
Bggi GGi 0 V=(v(Gi,Ki)+Vg0)*(1/(1+kIsr*max(0, v(G,Ki)+Vg0))) - gft1*v(ft) - gft1a*v(ft)/(1+kB*v(Ahc)) ;Effective internal grid voltage.
Bahc Ahc 0 V=uramp(v(A,Ki)) ;Anode voltage, hard cut to zero @ neg. value
Bst   St 0 V=uramp(max(v(GGi)+v(A,Ki)/(mu), v(A,Ki)/kp*ln(1+exp(kp*(1/mu+v(GGi)/(1+v(Ahc)))))));Steering volt.
Bs    Ai Ki I=os/ks*pow(v(St),xs) ;Langmuir-Childs law for the space charge current Is
*Bstrc Strc 0 V=uramp(max(v(GGi)+v(Ahc)/(murc), v(Ahc)/kprc*ln(1+exp(kprc*(1/murc+v(GGi)/(1+v(Ahc)))))));FOR REMOTE CUTOFF TUBES ONLY
*Bsrc   Ai Ki I=os/ksrc*pow(v(Strc),xs) ;FOR REMOTE CUTOFF TUBES ONLY
*
*Anode current limit @ small Va
.func smin(z,y,k) {pow(pow(z+1f, -k)+pow(y+1f, -k), -1/k)} ;Min-function with smooth trans.
.func ssmin(z,y,k) {min(min(z,y), smin(z*1.003,y*1.003,k))};smin-function which suppresses small residual differencies
Ra  A Ai 1
Bgl Gi A I=uramp(i(Ra)-ssmin(1/kl*pow(v(Ahc),xl),i(Ra),tsh)) ;Ia emission limit
*
*Grid model
Rgk G K 10G ;avoids "floating net" errors
Bvdg G Gi I=1/kvdg*pow(v(G,Gi),1.5) ;Reduces the internal effective grid voltage when Ig rises
Bcoh G Gi I=pow(uramp(v(G,Gi)-Vdrmax),2) ;A convergence help which softly limits the internal Vg voltage drop.
Rgip G Gi 1G ;avoids some warnings
.func fVT() {VT*exp(-kVT*sqrt(v(A,Ki)))}
.func Ivd(Vvd, kvd, xvd, VTvd)  {if(Vvd < 3, 1/kvd*pow(VTvd*xvd*ln(1+exp(Vvd/VTvd/xvd)),xvd), 1/kvd*pow(Vvd, xvd))} ;Vacuum diode function
Bgvd G Ki I=Ivd(v(G,Ki) + Vctg + min(0,v(A,Ki)/mu), kg/os, xg, fVT()) ;limits the internal Vg for convergence reasons
Bstn Stn 0 V=v(GGi)+min(0,v(A,Ki))/mu ;special steering voltage, sensitive to negative Anode voltages only
Bgr Gi Ai I= ivd(v(Stn),ks/os, xs, rTr*fVT())/(1+(kB+v(ft)*gft2)*v(Ahc));Is reflection to grid when Va approaches zero
*Bgr Gi Ai I=(ivd(v(Stn),ks/os, xs, rTr*fVT())+os/ksrc*pow(v(GGi),xs))/(1+(kB+v(ft)*gft2)*v(Ahc));FOR REMOTE CUTOFF TUBES ONLY
Bs0 Ai Ki  I=uramp(ivd(v(Stn),ks/os, xs, rTr*fVT()) - os/ks*pow(v(Stn),xs))
Bbatt Ki K V=Vbatt/2 ;for battery heated triodes; Offsets the average cathode potential to the half heater battery voltage
*
*Caps
C1 A G {cag}
C2 A K {cak}
C3 G K {cgk}
.ends
*
*Version log
*i1 :Initial version
*i2 :Pin order changed to the more common order A G K (Thanks to Markus Gyger for his tip)
*i3 :bugfix of the Ivd-function: now also usable for larger Vvd
*i4: Rgi replaced by a virtual vacuum diode (better convergence). ft1 deleted (no longer needed)
;2 new params for Ig finetuning @ Va and Vg near zero. New overall scaling factor os for aging etc.
*i5: improved convergence performance. PosVg/NegVa area now correct. Also accurate now for remote cutoff triodes!
 

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  • fit_6BN4A_goldenSample_Ia.png
    fit_6BN4A_goldenSample_Ia.png
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  • fit_6BN4A_goldenSample_IogIg.png
    fit_6BN4A_goldenSample_IogIg.png
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Adrian, thanks again for another great looking model. I have a question about 6BN4A....

6BN4A looks a lot like the triode in the twin-triodes 6BQ7 and 6BZ7. No?

6BQ7A data sheet: https://frank.pocnet.net/sheets/093/6/6BQ7A.pdf

6BZ7 data sheet: https://frank.pocnet.net/sheets/093/6/6BZ7.pdf

6BN4 data sheet: https://frank.pocnet.net/sheets/093/6/6BN4.pdf

All three have mu about 40, gm about 7mA/V, rp about 5k ohms.
6BQ7A and 6BN4 have the same plate-grid capacitance, 1.2pF.
6BZ7 has Cp-g of 1.8pF.

??
 

Koonw

Member
2013-04-09 9:37 pm
Try this 1L4 Brimar model (similar to DF92 u=11):

Code:
**** 1L4_BM ******************************************
* Created on 03/05/2022 11:08 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: 1L4_BM.png
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT 1L4_BM P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT 1L4_BM P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=15.39 KG1=8020.53 KP=302.9 KVB=101.76 VCT=0.32 EX=1.358 KG2=7348.32 KNEE=6.838 KVC=2.039
+ KLAM=4.598E-10 KLAMG=8.497E-11 KNEE2=5.48 KNEX=0.00116  KNK=-0.07986 KNG=0.006 KNPL=51 KNSL=11 KNPR=121.2 KNSR=27.84
+ CCG=3.6P CGP=0.008P CCP=7.5P VGOFF=-0.6 IGA=0.001 IGB=0.3 IGC=8 IGEX=2
* Vp_MAX=200 Ip_MAX=5 Vg_step=1 Vg_start=0 Vg_count=9
* X_MIN=31 Y_MIN=117 X_SIZE=823 Y_SIZE=506 FSZ_X=1296 FSZ_Y=736 XYGrid=false
* Rp=1400 Vg_ac=20 P_max=0.25 Vg_qui=-4 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=90 gridLevel2=y addKink=y isTanhKnee=y advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

Attachments

  • 1L4_BM paint.png
    1L4_BM paint.png
    327.9 KB · Views: 34
I can't find any 6BN4A/6BQ7A/6BZ7/6BN4 datasheet claiming Cpg = 1.8pF. Perhaps a misunderstanding?

However, please note that the 6BN4A has a 15% larger gm than the 6BN4. Their electrode construction is similar, but not identical.

You know... You're right! I'm not sure what I thought I saw.

I see from its datasheet that 6BN4A has gm = 7.7mA/V at Va = 150V, Ia = 9mA, and Vg = -2V.
That is a higher gm than 6BN4 (no "A") at 6.8mA/V or 6BQ7A at 6.4mA/V.

Thanks for clearing that up.
 

Koonw

Member
2013-04-09 9:37 pm
This GU81 model fixed Ig2 distortion in triode mode:

Code:
**** GU81 *****************************Fixed Ig2 distortion in triode mode*************
* Created on 03/07/2022 20:41 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: GU81.jpg
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT GU81 P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT GU81 P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=3.222 KG1=2317.17 KP=50.56 KVB=1053.04 VCT=-0.1625 EX=1.31 KG2=2820.94 KNEE=205.1 KVC=1.744
+ KLAM=3.052E-14 KLAMG=2.102E-5 KNEE2=65.37 KNEX=166.47  KNK=1.92 KNG=0.007113 KNPL=4.665E-9 KNSL=18291.73 KNPR=11978.27 KNSR=4.615E6
+ CCG=32P CGP=0.1P CCP=26P VGOFF=-0.6 IGA=0.001 IGB=0.465 IGC=1.68 IGEX=1.84
* Vp_MAX=3200 Ip_MAX=1600 Vg_step=40 Vg_start=80 Vg_count=17
* X_MIN=81 Y_MIN=29 X_SIZE=776 Y_SIZE=633 FSZ_X=1296 FSZ_Y=736 XYGrid=true
* Rp=1400 Vg_ac=20 P_max=450 Vg_qui=-240 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=500 gridLevel2=y addKink=y isTanhKnee=y advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

Attachments

  • gu81 paint-2.png
    gu81 paint-2.png
    494.6 KB · Views: 22

Koonw

Member
2013-04-09 9:37 pm
KT170 Tung-Sol model:

Code:
**** KT170 ******************************************
* Created on 03/09/2022 08:16 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: kt170.png
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT KT170 P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT KT170 P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=6.945 KG1=1595.84 KP=43.97 KVB=267.48 VCT=-1 EX=1.477 KG2=2555.04 KNEE=8.862 KVC=2.082
+ KLAM=1.192E-10 KLAMG=5.767E-4 KNEE2=8.118 KNEX=2.103  KNK=-0.01984 KNG=0.01526 KNPL=24.4 KNSL=20.41 KNPR=110.34 KNSR=70.72
+ CCG=14P CGP=0.85P CCP=12P VGOFF=-1.5 IGA=0.002788 IGB=0.156 IGC=6.16 IGEX=1.86
* Vp_MAX=500 Ip_MAX=300 Vg_step=5 Vg_start=0 Vg_count=17
* X_MIN=75 Y_MIN=80 X_SIZE=707 Y_SIZE=566 FSZ_X=1296 FSZ_Y=736 XYGrid=false
* Rp=1400 Vg_ac=20 P_max=85 Vg_qui=-40 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=225 gridLevel2=y addKink=y isTanhKnee=y advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

Attachments

  • KT170 paint-1.png
    KT170 paint-1.png
    409 KB · Views: 41
  • KT170 transfer curve compared.png
    KT170 transfer curve compared.png
    185.6 KB · Views: 48
Hi,
does anybody has a Model for the 5672 subminiature tube?

I tried using Paint_kit and had some success with the triode mode curves, but could not match the pentode curves.
Do the parameters need to be the same when using paint_kit and paint_kip? The triode strapped mode of paint_kip also did not produce similar results.
5672_Triode_paint.png
 

Koonw

Member
2013-04-09 9:37 pm
Try to merge the pentode and triode curve, Mu used is same as triode (Pentode has it's own Mu=Gm*Rl). I can't find the interelectrode capacitance, if you find it, replaced them. 5672P Tung-Sol model:

Code:
**** 5672P ******************************************
* Created on 03/30/2022 15:39 using paint_kip.jar
* www.dmitrynizh.com/tubeparams_image.htm
* Plate Curves image file: 5672p.png
* Data source link: <plate curves URL>
*----------------------------------------------------------------------------------
.SUBCKT 5672P P G2 G K ; LTSpice tetrode.asy pinout
* .SUBCKT 5672P P G K G2 ; Koren Pentode Pspice pinout
+ PARAMS: MU=5.145 KG1=13178.88 KP=59.91 KVB=227.4 VCT=-0.68 EX=1.442 KG2=15370.28 KNEE=19.44 KVC=1.908
+ KLAM=9.5E-8 KLAMG=2.505E-4 KNEE2=4.559 KNEX=5.7  KNK=-0.044 KNG=0.006 KNPL=50 KNSL=11 KNPR=120 KNSR=29
+ CCG=3P CGP=1.4P CCP=1.9P VGOFF=-0.6 IGA=0.001 IGB=0.3 IGC=8 IGEX=2
* Vp_MAX=150 Ip_MAX=10 Vg_step=4 Vg_start=0 Vg_count=9
* X_MIN=74 Y_MIN=92 X_SIZE=717 Y_SIZE=545 FSZ_X=1298 FSZ_Y=738 XYGrid=false
* Rp=1400 Vg_ac=20 P_max=0.5 Vg_qui=-16 Vp_qui=300
* showLoadLine=n showIp=y isDHP=n isPP=n isAsymPP=n isUL=n showDissipLimit=y
* showIg1=y isInputSnapped=y addLocalNFB=n
* XYProjections=n harmonicPlot=y dissipPlot=n
* UL=0.43 EG2=67.5 gridLevel2=y addKink=y isTanhKnee=y advSigmoid=n
*----------------------------------------------------------------------------------
RE1  7 0  1G    ; DUMMY SO NODE 7 HAS 2 CONNECTIONS
E1   7 0  VALUE=  ; E1 BREAKS UP LONG EQUATION FOR G1.
+{V(G2,K)/KP*LOG(1+EXP((1/MU+(VCT+V(G,K))/SQRT(KVB+V(G2,K)*V(G2,K)))*KP))}
RE2  6 0  1G    ; DUMMY SO NODE 6 HAS 2 CONNECTIONS
E2  6 0  VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))} ; Kg1 times KIT current
RE21 21 0 1
E21  21 0 VALUE={V(6)/KG1*ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2)} ; Ip with knee but no slope and no kink
RE22 22 0 1 ; E22: kink curr deviation for plate
E22  22 0 VALUE={V(21)*LIMIT(KNK-V(G,K)*KNG,0,0.3)*(-ATAN((V(P,K)-KNPL)/KNSL)+ATAN((V(P,K)-KNPR)/KNSR))}
G1   P  K  VALUE={V(21)*(1+KLAMG*V(P,K))+KLAM*V(P,K) + V(22)}
* Alexander Gurskii screen current, see audioXpress 2/2011, with slope and kink added
RE43 43 K 1G ; Dummy
E43  43 G2 VALUE={0} ; Dummy
G2   43 K  VALUE={V(6)/KG2*(KVC-ATAN((V(P,K)+KNEX)/KNEE)*TANH(V(P,K)/KNEE2))/(1+KLAMG*V(P,K))-V(22)}
RCP  P K  1G     ; FOR CONVERGENCE
C1   K G  {CCG}  ; CATHODE-GRID 1
C2   G P  {CGP}  ; GRID 1-PLATE
C3   K P  {CCP}  ; CATHODE-PLATE
RE23 G 0 1G
GG G K VALUE={(IGA+IGB/(IGC+V(P,K)))*(MU/KG1)*
+(PWR(V(G,K)-VGOFF,IGEX)+PWRS(V(G,K)-VGOFF,IGEX))}
.ENDS
*$
 

Attachments

  • 5672p paint-1.png
    5672p paint-1.png
    480.3 KB · Views: 14