Spice model for 811a A2 Grid

[hacknet]

Hi!

Glad to be back after almost a decade, any one has a good spice model for the grid circuit of a 811A?

I'm using this at the moment and the grid current draw in A2 mode doesnt seem right.

At 430v @ 100ma, Vg +22, the model only draws 3ma, I believe from reading tubelabs comments in 2007, Ig should be like 20ma or there abouts.

any help is greatly appreciated


.subckt 811a 1 2 3 ;
+ params: mu=160 ex=1.317 kg1=1350 kp=100 kvb=1400 rgi=2000
+ ccg=2.3p cgp=2.4p ccp=.9p
+ a=1.6667e-10 b=-.0000002875 c=0.0001758333 d=1.275
e1 7 0 value=
+{v(1,3)/kp*log(1+exp(kp*(1/mu+v(2,3)/sqrt(kvb+v(1,3)*v(1,3)))))}
re1 7 0 1g
e2 8 0 value=
+{a*v(1,3)*v(1,3)*v(1,3)+b*v(1,3)*v(1,3)+c*v(1,3)+d}
re2 8 0 1g
e3 9 0 table {v(2,3)} =
+ (-1 1.1e-16)
+ (0, .6e-4) (20, 5.38e-4)
+ (40, 6.25e-4) (60, 7.41e-4)
re3 9 0 1g
g1 1 3 value= {(pwr(v(7),v(8))+pwrs(v(7),v(8)))*v(9)}
rcp 1 3 100k
c1 2 3 {ccg}
c2 1 2 {cgp}
c3 1 3 {ccp}
r1 2 5 {rgi}
d3 5 3 dx
.model dx d(is=70u rs=1 cjo=1pf N=180)
.ends

 

[euro21]

Try Adrian Immler version:
https://www.diyaudio.com/forums/tubes-valves/243950-vacuum-tube-spice-models-197.html#post5731136

 

[hacknet]

you are absolutely right. works like a charm!

 

[Zoran]

Hi I cant reach the model for 811A with this link?
Please point the page and post number?
cheers 🙂

 

[euro21]

Search it on Adrian's site:
https://adrianimmler.simplesite.com/448181484.html

 

[Zoran]

Thanks