I have fought with the Windows XP machine for over a week, countless hours put in including re-installing XP, only to find a couple of seeming major flaws: no way to select the input tubes and no way to change the OPTs (despite what it says). I did look through the program to no avail. So then how do you simulate a specific schematic, please?
And no, it is not intuitive... At least so far. 🙂
1964-1966. One of many inventors going back to 1846. Yes, the Xerox is one of the ones which did not need porters and chemists.
On the side: an interesting mention of the idea, then called 'wire photo', is in Hoofbeats on the Turnpike, by Mildred A. Wirt, 1944. There is a dam disaster up-state. Girl Reporter Penny has pictures but the railroad and the highway are flooded out. She manages to call her paper. Real 1940s jargon.
Ambulances, army and supply trucks now were flowing into Delta in a steady stream. However, midway there, they spied a car coming toward them which bore “Riverview Star” on its windshield.
....Penny and Louise squeezed into the front seat of the sedan. Driving on, Salt plied them with questions. Penny told him how rival newsmen had tried to buy her camera pictures.
“Good for you, hanging onto them!” Salt approved warmly. “Our car never did break down. By the way, where can we set up our portable wire photo equipment?”
“There’s only one possibility. The telephone company. Right now they have the only wire service in Delta.”
Penny directed Salt through the few streets that were clear of debris to the telephone building. There the portable wire photo equipment quickly was set up. Penny’s camera pictures were developed, and though some of the shots were over-exposed there were four good enough to send over the network.
“Mr. Nordwall has six toll lines out of Delta now,” Salt told the girls jubilantly. “He’s letting us have one of them.”
Carefully the photographer tested the controls of the wire photo machine. He listened briefly to the hum of the motor. Satisfied that everything was running properly, he attached one of the freshly printed pictures to the transmitting cylinder.
“Okay,” he signaled to Mr. Nordwall. “Give us a toll to the Riverview Star.”
Within a few minutes the order came: “Network clear. Go ahead, Delta.”
Salt turned on a switch and the sending cylinder began to revolve. One by one Penny’s pictures were transmitted over the wire.
“Your shots are the first to get out of Red Valley!” Salt told her triumphantly. “Your work’s done now. Better crawl off somewhere and sleep.”
Penny nodded wearily. She was glad to know that the Star would scoop every other paper in the country on the flood story and pictures.
January 1, 1944
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You have it set to simulate a cathode follower totem pole - there is no OPT.
Select Gnd-Cathode Transformer instead...
To change the tube parameters, select User Defined from the bottom of the list...
Here's a shot of a sim of a Modular Amplifier with 6P45S outputs.
Wow, thank you so very much! 😀 If you were closer, I at least buy you a root beer.
Well then, how do I get these schematic files, please?
Okay, I will do that.
PM sent.
If I am seeing correctly, one doesn't need training, just logic?
Here is my guess:
* EL84 maximum ratings:
*
- PIV 600V
- Max in 300V RMS
- Iout 65mA DC output current (per anode)
- Ia pk 48mA repetitive (2200mA transient)
*
- .----- Anode
- | .--- Cathode
- | |
GP A K VALUE={2.69E-4*(PWR(V(A,K),1.5)+PWRS(V(A,K),1.5))/2}
.ENDS EL84
Neat! 😀
Thank you! 😀
Is Select Gnd-Cathode Transformer the option to always use when evaluating amplifier circuits?
All I know is one is cathodyne and one is LTP. So for these two, what do I select?
How do I change the input tubes (ECF80 and EF86)?
Turns out none of them quite match exactly, does this matter for high level evaluation?
I am getting the feeling Spice is more accurate, so provides more accurate and detailed results. However, TCJ was on my screen and being curious to see if runs on Windows 7, allowed myself to be distracted...
The secondary's resistance is not a value that I can find, assumed since a high quality OPT used 0,3Ω.
Can one know from a schematic the idle current (Vg bias)?
What about "Target Iq (mA)"? Taking a WAG, maximum plate dissipation is 12 watts, 325 volts is going in, so using the elementary formula, that be 36.92mA maximum. Using "Find" give a Vg Bias of of -1,4VDC (115VAC PS) - 2VDC (125VAC PS). Interesting that it is negative and so low.
Then there is the peak signal VAC. Well, RCA gives 5,7W and 50,6mA, Sylvania interestingly gives values for 250VDC and 300VDC plate voltages: 62-74mA and 72-92mA, receptively, and Telefunken doesn't seem to give a value. Looking back to RCA, see the plate voltage is 250VDC, so 65mA (thinking logically, 11 percent over isn't going to kill a tube) is a good value for 250VDC and assuming German tubes are of equal or higher quality to American, use 90mA for 300VDC. Using Ohm's law, using the typical 4.5000Ω plate resistance, come to 292,5VAC and 405VAC, respectively. Find it odd then the default is at 87VAC.
Well, past lunch time and still have to heat it up, better sign off and come back with a run, unless some generous person provides assistance. 🙂
Turns out TCJ does run on Windows 7. However, something doesn't seem right with the results, either using calculated VAC maximum signal or in automatic mode. Once the bugs are worked out, can see how a useful teaching tool and maybe design tool, in can quickly view results, especially with array.
Just to show the graphs are generating.
Installing Spice now, then a 50 minute meeting.
Just to show the graphs are generating.
Installing Spice now, then a 50 minute meeting.
Huge shout out to José (@jcalvarez ) for providing not only the schematic, also for tube file and library, including transformer blocks (love to learn how to create, looked at the text and couldn't see how to edit, not in MDOS (done a little for an energy evaluation program years ago))!
Man Spice is addicting! Where did the time go?
First, ran a square wave of 10kHz though (going by memory of what the instructions were) and adjusted the feedback:
5K
10K (Revision E)
12K (Revision F)
15K
20K
50K
Lesson I learned from adjusting values is takes large changes from ideal to make an impact. Put in a 5K and a 50K potentiometer adjust the feedback for desired sound without detrimental distortion/harmonics based on this data; double check once built with REW or an oscilloscope.
Interestingly, didn't affect distortion, until...
No feedback. Oh my...
Here is the ECF80/6BL8 with the 12k resistor.
Finally, tube rolled in ECF82/6U8s and wow, think this is an improvement, went from -35dB to -50dB on the second. I did try increasing the plate voltage (per the data sheet can handle twice) though seemed to make no difference. I probably don't know enough to change the schematic for optimum tube roll.
Man Spice is addicting! Where did the time go?
First, ran a square wave of 10kHz though (going by memory of what the instructions were) and adjusted the feedback:
5K
10K (Revision E)
12K (Revision F)
15K
20K
50K
Lesson I learned from adjusting values is takes large changes from ideal to make an impact. Put in a 5K and a 50K potentiometer adjust the feedback for desired sound without detrimental distortion/harmonics based on this data; double check once built with REW or an oscilloscope.
Interestingly, didn't affect distortion, until...
No feedback. Oh my...
Here is the ECF80/6BL8 with the 12k resistor.
Finally, tube rolled in ECF82/6U8s and wow, think this is an improvement, went from -35dB to -50dB on the second. I did try increasing the plate voltage (per the data sheet can handle twice) though seemed to make no difference. I probably don't know enough to change the schematic for optimum tube roll.
Huge shout out to José (@jcalvarez ) for providing not only the schematic, also for tube file and library, including transformer blocks (love to learn how to create, looked at the text and couldn't see how to edit, not in MDOS (done a little for an energy evaluation program years ago))!
Man Spice is addicting! Where did the time go?
First, ran a square wave of 10kHz though (going by memory of what the instructions were) and adjusted the feedback:
5KView attachment 1146313
10K (Revision E)
View attachment 1146314
12K (Revision F)
View attachment 1146315
15K
View attachment 1146316
20K
View attachment 1146317
50K
View attachment 1146318
Though at 50K it finally did affect distortion.
Lesson I learned from adjusting values is takes large changes from ideal to make an impact. Put in a 5K and a 50K potentiometer adjust the feedback for desired sound without detrimental distortion/harmonics based on this data; double check once built with REW or an oceliscope.
Interestingly, didn't affect distortion.
Onto no feedback, defiantly affected distortion.
View attachment 1146319
Here is the ECF80/6BL8 with the 12k resistor.
View attachment 1146320
Finally, tube rolled in ECF82/6U8s and wow, think this is an improvement, went from -35dB to -50dB on the second. I did try increasing the plate voltage (per the data sheet can handle twice) though seemed to make no difference. I probably don't know enough to change the schematic for optimum tube roll.
View attachment 1146321
Man Spice is addicting! Where did the time go?
First, ran a square wave of 10kHz though (going by memory of what the instructions were) and adjusted the feedback:
5KView attachment 1146313
10K (Revision E)
View attachment 1146314
12K (Revision F)
View attachment 1146315
15K
View attachment 1146316
20K
View attachment 1146317
50K
View attachment 1146318
Though at 50K it finally did affect distortion.
Lesson I learned from adjusting values is takes large changes from ideal to make an impact. Put in a 5K and a 50K potentiometer adjust the feedback for desired sound without detrimental distortion/harmonics based on this data; double check once built with REW or an oceliscope.
Interestingly, didn't affect distortion.
Onto no feedback, defiantly affected distortion.
View attachment 1146319
Here is the ECF80/6BL8 with the 12k resistor.
View attachment 1146320
Finally, tube rolled in ECF82/6U8s and wow, think this is an improvement, went from -35dB to -50dB on the second. I did try increasing the plate voltage (per the data sheet can handle twice) though seemed to make no difference. I probably don't know enough to change the schematic for optimum tube roll.
View attachment 1146321
Now you are rolling!
Reminds me of the days I used to teach people how to play squash, and they were beating me by game 4 🙂
Reminds me of the days I used to teach people how to play squash, and they were beating me by game 4 🙂
To some degree. The program seems logical and intuitive, maybe even easy. Think attempt a small circuit today. 🤔
Ha.
Well, lots more to learn! I asked a question or two here and got no answer, so look more and worse case post a dedicated thread in the correct sub forum (I doubt anyone who has not joined at the beginning dares to enter into this thread).
Thank you so very much! 😀 This forum needs a happy dance symbol, the Volkswagen forum does so it is out there, as really could use it right. now!
Weird Gmail is being finicky about attachments.
And yes, I will enjoy, especially once figure out how to view gain and watts average total.
If you look at the schematics, there are a couple of measure commands:
.meas TRAN power_Output AVG I(RL)*V(OUT) TRIG time=0 TARG time=nCycles*period/2
.meas TRAN Gain RMS (V(OUT))/{InputVoltageRms} TRIG time=0 TARG time=NCycles*period/2
After running the simulation, you can see the distortion figures, power_Output and Gain, by clicking "View->Spice Error log", you will see something like this: