I do not have any schematic at the moment but I am interesting to put the tubes in good use. I have 10 of 6360 and think that it might be great if I can put these double tetode in action - SE or PP. I am quiet new with tube, actually have no knowledge relating to electronic.
Appreciate any thought or schematic.
Appreciate any thought or schematic.
Hi,
Do a search on this forum - I previously commented how I was impressed with this tube when parallel/triode-connected. There was some reservation expressed at the time re screen-grid voltage ratings, but I have no reservations up to 300v+.......
I confess to not having progressed from graphing characteristics; got side-tracked into developing suitable output transformers! These are now completed and very successful too.
My bench is littered with books, papers, and tubes as I swing from idea to idea - impressed with Pointz' triode 6V6s as I also have many of the Brimar 6BW6 (noval 6V6 for which they quote better distortion figures) Recent purchases have brought my holding of 7236 tubes upwards of a dozen and this has caused me to act like the legendary John Gilpen ie striding from the room, leaping on my horse (literally) and furiously galloping off in all directions at once.........
If you pursue the 6360 tube, I can only emphasise the previous post harking to it being an RF tube, and stress the correct use of grid-stoppers.
G
Do a search on this forum - I previously commented how I was impressed with this tube when parallel/triode-connected. There was some reservation expressed at the time re screen-grid voltage ratings, but I have no reservations up to 300v+.......
I confess to not having progressed from graphing characteristics; got side-tracked into developing suitable output transformers! These are now completed and very successful too.
My bench is littered with books, papers, and tubes as I swing from idea to idea - impressed with Pointz' triode 6V6s as I also have many of the Brimar 6BW6 (noval 6V6 for which they quote better distortion figures) Recent purchases have brought my holding of 7236 tubes upwards of a dozen and this has caused me to act like the legendary John Gilpen ie striding from the room, leaping on my horse (literally) and furiously galloping off in all directions at once.........
If you pursue the 6360 tube, I can only emphasise the previous post harking to it being an RF tube, and stress the correct use of grid-stoppers.
G
thank Graeme .....
I actually did read our opinion on the 6360 even some might experience differently.
Even so, I really like to use the tube as power tube by pararelling both plates. What I'm wondering whether I should tie G2 to plate or to G1.
I like small amp with few tubes and I am current very much happy with 12B4A SE amp that I had built. I like the way the amp convey music especially to my taste.
Anyway, I also like to experience with other tubes sound ........
I actually did read our opinion on the 6360 even some might experience differently.
Even so, I really like to use the tube as power tube by pararelling both plates. What I'm wondering whether I should tie G2 to plate or to G1.
I like small amp with few tubes and I am current very much happy with 12B4A SE amp that I had built. I like the way the amp convey music especially to my taste.
Anyway, I also like to experience with other tubes sound ........
8watt amp
An idea for a PP 6360 Amplifier --
Here's a SPICE model for the 6360:
.subckt 6360Tetrode 1 2 3 4
+Params: MU=9.38 KP=41.82 KVB=11.27 EX=1.15 KG1=898.6
E1 7 0 Value = {(V(2,4)/KP)*LN((1+ EXP((KP/MU) + ((KP*(V(3,4)))/(V(2,4))))))}
RE1 7 0 1e12
G1 1 4 VALUE = {(((V(7))^EX)/KG1)*(1+SGN(V(7)))*(ATAN(V(1,4)/KVB))}
RCP 1 4 1e12
C1 3 4 2.3e-12
C2 1 3 2.1e-12
C3 1 4 0.7e-12
R1 3 5 1000
D3 5 4 dx
.model dx d(is=1e-09 rs=1 cjo=10e-12)
.ends
An externally hosted image should be here but it was not working when we last tested it.
Here's a SPICE model for the 6360:
.subckt 6360Tetrode 1 2 3 4
+Params: MU=9.38 KP=41.82 KVB=11.27 EX=1.15 KG1=898.6
E1 7 0 Value = {(V(2,4)/KP)*LN((1+ EXP((KP/MU) + ((KP*(V(3,4)))/(V(2,4))))))}
RE1 7 0 1e12
G1 1 4 VALUE = {(((V(7))^EX)/KG1)*(1+SGN(V(7)))*(ATAN(V(1,4)/KVB))}
RCP 1 4 1e12
C1 3 4 2.3e-12
C2 1 3 2.1e-12
C3 1 4 0.7e-12
R1 3 5 1000
D3 5 4 dx
.model dx d(is=1e-09 rs=1 cjo=10e-12)
.ends
The maximum screen voltage of 6360 is specified as 200 V.
I have built 10 W pp amplifier with 6360 (QQE03/12) and used 220 V, because it gave better linearity.
I have built 10 W pp amplifier with 6360 (QQE03/12) and used 220 V, because it gave better linearity.
An externally hosted image should be here but it was not working when we last tested it.
6F12 Triode SPICE Model -- I tried limiting EX to 1.5, but it comes up a little better with a higher value:
.subckt 6F12 1 2 3
+Params: MU=111 KP=1449 KVB=9780 EX=1.527 KG1=100.7
E1 7 0 Value = {(V(1,3)/KP)*LN((1+ EXP((KP/MU) + ((KP*(V(2,3)))/(SQRT(KVB+V(1,3)*V(1,3)))))))}
RE1 7 0 1e12
G1 1 3 VALUE = {(((V(7))^EX)/KG1)*(1+SGN(V(7)))}
RCP 1 3 1e12
C1 2 3 4.6e-12
C2 1 2 1.6e-12
C3 1 3 0.26e-12
R1 2 5 2000
D3 5 3 dx
.model dx d(is=1e-09 rs=1 cjo=10e-12)
.ends
.subckt 6F12 1 2 3
+Params: MU=111 KP=1449 KVB=9780 EX=1.527 KG1=100.7
E1 7 0 Value = {(V(1,3)/KP)*LN((1+ EXP((KP/MU) + ((KP*(V(2,3)))/(SQRT(KVB+V(1,3)*V(1,3)))))))}
RE1 7 0 1e12
G1 1 3 VALUE = {(((V(7))^EX)/KG1)*(1+SGN(V(7)))}
RCP 1 3 1e12
C1 2 3 4.6e-12
C2 1 2 1.6e-12
C3 1 3 0.26e-12
R1 2 5 2000
D3 5 3 dx
.model dx d(is=1e-09 rs=1 cjo=10e-12)
.ends
This is the triode model I have found somewhere and used with good results:
.SUBCKT 6F12P-T 1 2 3 ; P G C (Triode)
+ PARAMS: MU=112.5 EX= 1.66 KG1= 94 KP=760
+ KVB=12100.0 VCT= 0.00 RGI=4500
+ CCG=4.6P CGP=1.6P CCP=0.26P
E1 7 0 VALUE=
+{V(1,3)/KP*LN(1+EXP(KP*(1/MU+(V(2,3)+VCT)/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 IN MU-FOLLOWER
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
I have no knowledge how to make and modufy these models.
What is this EX ?
.SUBCKT 6F12P-T 1 2 3 ; P G C (Triode)
+ PARAMS: MU=112.5 EX= 1.66 KG1= 94 KP=760
+ KVB=12100.0 VCT= 0.00 RGI=4500
+ CCG=4.6P CGP=1.6P CCP=0.26P
E1 7 0 VALUE=
+{V(1,3)/KP*LN(1+EXP(KP*(1/MU+(V(2,3)+VCT)/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 IN MU-FOLLOWER
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
I have no knowledge how to make and modufy these models.
What is this EX ?
I download the data == either from the datasheet or my 576 curve tracer and use Graph Grabber to create a CSV file.
The equations are written in Excel format to calculate E1 and G1, holding the parameters constant use Excel Solver to optimize the values. I find that minimizing the log squashed error gives pretty good results for triodes. For pentodes and tetrodes I use a measure of "goodness of fit".
It's a good idea to set the "Options" in solver so that you can watch the iterations. Sometimes it will skip over the solution which is best for your application.
EX is the exponential term relating Ia to Vgk, Vk -- it should be less than 3/2, but for some valves it may be a bit larger. I set limits to EX such that it falls in a range of 1.1 to 1.6.
I haven't modeled the screen current of the 6F12P yet, but have one that seems to work for Ia:
.subckt 6F12PENT 1 2 3 4
+Params: MU=68.7 KP=6032.7 KVB=6.048 EX=1.515 KG1=315.5 EX2=1.41 K7=2.81E-4
E1 7 0 Value = {(V(2,4)/KP)*LN((1+ EXP((KP/MU) + ((KP*(V(3,4)))/(V(2,4))))))}
RE1 7 0 1e12
G1 1 4 VALUE = {MIN((((V(7))^EX)/KG1)*(1+SGN(V(7)))*(ATAN(V(1,4)/KVB)),(K7*(V(1,4)^EX2)))}
RCP 1 4 1e12
C1 3 4 6.6e-12
C2 1 3 1.9e-12
C3 1 4 0.01e-12
R1 3 10 2000
D3 10 4 dx
.model dx d(is=1e-09 rs=1 cjo=10e-12)
.ends
An externally hosted image should be here but it was not working when we last tested it.
Here's the 6F12P model pulled off the web, and the one which was subjected to "Solver"
Important to remember with tubes, that it's just an approximation.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Important to remember with tubes, that it's just an approximation.
I think you need to replace all the "^"s with "**" in LTSpice. Since you already built the amp, it would be great to compare the models with the actual tube's performance, looking forward to see some comparisons
Hi Jack,
I tried the spice model on TINA-TI, but it said "syntax error" on Line 3.....
How should I modify the equation?
cheers
Coffin
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.