Tag: D3a triode

300B SE Amplifier Finished!

When everything was going to plan…

This build became one of the quickest and eventually the most painful from all, perhaps not really. However, it was very challenging in the end. I will tell you why in more detail. Yet, it has been a fantastic learning experience.

Continue reading “300B SE Amplifier Finished!”

Russian pentodes in triode mode

After some proper time tracing the curves, here are a set of Russian high-frequency pentodes in triode-mode for comparison. I was looking at closer ones to D3a and these are the ones I had at hand and wanted to include in the tests:

6Z5P 6Z9P 6Z11P 6Z49P-D 6Z51P 6P15P 6E5P 6E6P-E D3a
Vf [V] 6.3 6.3 6.3 6.3 6.3 6.3 6.3 6.3 6.3
If [ma] 450 300 440 300 300 760 600 610 315
Pa [W] 4 3.75 6 3.4 3.5 13.5 10.6 8.8 4.5
Gm [ma/V] 7 35 33 17.75 29 16 32 25 34
μ 44 36 40 44.3 79.5 22 30 34 68
Ra [Ω] 6K2 1k 1K2 2K5 2K7 1K6 960 1K3 2K
Ia [ma] 16 29 40 15.7 23 52 50 30 22
Va [V] 252 125 150 200 150 250 200 200 200

Well, as you can see in the table above, the 6e5p and 6e6p-e (both tetrodes) were included in the list.  Some interesting points to highlight:

Continue reading “Russian pentodes in triode mode”

C3g and D3a triode SPICE models

Using my C3g and D3a triode curves, I developed the following SPICE models:

D3a triode SPICE

 

** D3A TRIODE ************************************************************
* Created on Sat Jan 12 09:17:53 GMT 2013 using tube.model.finder.PaintKIT
* model URL: http://www.bartola.co.uk/valves/valve-curves/d3a-triode/
* Created by Ale Moglia [email protected]
*--------------------------------------------------
.SUBCKT TRIODE_D3A 1 2 3 ; P G K ; 
+ PARAMS: CCG=6.7P CGP=3.3P CCP=1P RGI=2000
+ MU=72.1 EX=1.456 KG1=65.625 KP=534.0 KVB=300.0 VCT=0.0557 ; Vp_MAX=500.0 Ip_MAX=0.07 Vg_step=0.5
*--------------------------------------------------
E1 7 0 VALUE={V(1,3)/KP*LOG(1+EXP(KP*(1/MU+(VCT+V(2,3))/SQRT(KVB+V(1,3)*V(1,3)))))} 
RE1 7 0 1G 
G1 1 3 VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))/KG1} 
RCP 1 3 1G ; TO AVOID FLOATING NODES
C1 2 3 {CCG} ; CATHODE-GRID 
C2 2 1 {CGP} ; GRID=PLATE 
C3 1 3 {CCP} ; CATHODE-PLATE 
D3 5 3 DX ; FOR GRID CURRENT 
R1 2 5 {RGI} ; FOR GRID CURRENT 
.MODEL DX D(IS=1N RS=1 CJO=10PF TT=1N) 
.ENDS 
*$

C3G triode SPICE modelC3g triode SPICE

 

** C3G TRIODE ************************************************************
* Created on Sat Jan 12 09:40:08 GMT 2013 using tube.model.finder.PaintKIT
* model URL: http://www.bartola.co.uk/valves/valve-curves/c3g-pentodetriode/
* Created by Ale Moglia [email protected]
*--------------------------------------------------
.SUBCKT TRIODE_C3G 1 2 3 ; P G K ; 
+ PARAMS: CCG=7P CGP=2.7P CCP=6P RGI=2000
+ MU=50.4 EX=1.428 KG1=199.6875 KP=426.0 KVB=204.0 VCT=0.5760 ; Vp_MAX=500.0 Ip_MAX=0.07 Vg_step=1.0
*--------------------------------------------------
E1 7 0 VALUE={V(1,3)/KP*LOG(1+EXP(KP*(1/MU+(VCT+V(2,3))/SQRT(KVB+V(1,3)*V(1,3)))))} 
RE1 7 0 1G 
G1 1 3 VALUE={(PWR(V(7),EX)+PWRS(V(7),EX))/KG1} 
RCP 1 3 1G ; TO AVOID FLOATING NODES
C1 2 3 {CCG} ; CATHODE-GRID 
C2 2 1 {CGP} ; GRID=PLATE 
C3 1 3 {CCP} ; CATHODE-PLATE 
D3 5 3 DX ; FOR GRID CURRENT 
R1 2 5 {RGI} ; FOR GRID CURRENT 
.MODEL DX D(IS=1N RS=1 CJO=10PF TT=1N) 
.ENDS