Dissimilar triodes in parallel.
Posted: Wed Jun 06, 2012 11:27 pm
a guy on the asylum was interested in putting a 300B in parallel with a KT-90.
I know it sounds like the beginning of a bad joke, but I think he should try it just for kicks. (he posted about it a year or so ago and was shot down by those who "know")
I did a few crude sims and NAZ asked for the files. Rather than bury them with the rest of my asylum dreck, I though I'd open up the discussion here. I'd actually prefer the discussion to continue at the asylum but I use this forum as an easy way to host the needed files.
The KT90 model needs to be added to your triodenh file (where the rest of your models are) and then you need to select the 300B model you want. I used a version I traced in the same way I did the KT90. Please note, I don't bother with the capacitances on any of my models.
All props go to stephie for being the great teacher that she is.
* KT90 LTSpice model
.subckt KT90 P G K
Bp P K I=(0.01798272846m)*uramp(V(P,K)*ln(1.0+(-0.1903672493)+exp((0.1218980633)+(0.1218980633)*((104.4846442)+(27.71095382m)*V(G,K))*V(G,K)/sqrt((-1.365059137)**2+(V(P,K)-(-19.04749222))**2)))/(0.1218980633))**(1.412945234)
.ends KT90
* WE300b-2 LTSpice model
.subckt WE300b-2 P G K
Bp P K I=(0.1247974139m)*uramp(V(P,K)*ln(1.0+(-0.1272915694)+exp((15.16823755)+(15.16823755)*((4.15073619)+(1.520093533m)*V(G,K))*V(G,K)/sqrt((49.69832898)**2+(V(P,K)-(-2.804610879))**2)))/(15.16823755))**(1.499346998)
.ends WE300b-2
I know it sounds like the beginning of a bad joke, but I think he should try it just for kicks. (he posted about it a year or so ago and was shot down by those who "know")
I did a few crude sims and NAZ asked for the files. Rather than bury them with the rest of my asylum dreck, I though I'd open up the discussion here. I'd actually prefer the discussion to continue at the asylum but I use this forum as an easy way to host the needed files.
The KT90 model needs to be added to your triodenh file (where the rest of your models are) and then you need to select the 300B model you want. I used a version I traced in the same way I did the KT90. Please note, I don't bother with the capacitances on any of my models.
All props go to stephie for being the great teacher that she is.
* KT90 LTSpice model
.subckt KT90 P G K
Bp P K I=(0.01798272846m)*uramp(V(P,K)*ln(1.0+(-0.1903672493)+exp((0.1218980633)+(0.1218980633)*((104.4846442)+(27.71095382m)*V(G,K))*V(G,K)/sqrt((-1.365059137)**2+(V(P,K)-(-19.04749222))**2)))/(0.1218980633))**(1.412945234)
.ends KT90
* WE300b-2 LTSpice model
.subckt WE300b-2 P G K
Bp P K I=(0.1247974139m)*uramp(V(P,K)*ln(1.0+(-0.1272915694)+exp((15.16823755)+(15.16823755)*((4.15073619)+(1.520093533m)*V(G,K))*V(G,K)/sqrt((49.69832898)**2+(V(P,K)-(-2.804610879))**2)))/(15.16823755))**(1.499346998)
.ends WE300b-2