Sorry.
I'm afraid I wouldn't know what to do with source codes.
I've only just started using linux, and I don't even know too much about computers.
I just noticed that on your website you had the debian logo, and asumed that you were running that calculator with debian.
Nevermind, it's not too important. But thanks for the offer.
-Raphael.
I'm afraid I wouldn't know what to do with source codes.
I've only just started using linux, and I don't even know too much about computers.
I just noticed that on your website you had the debian logo, and asumed that you were running that calculator with debian.
Nevermind, it's not too important. But thanks for the offer.
-Raphael.
Running 'Squares'
Ive tried a few experiments with the air-gap and find that I get higher O/P and less distortion running a gap of .11mm as opposed to my original .22mm
I can now get a pretty respectable sine-wave at 15Hz, at 20W. Any less air-gap and saturation causes distortion ,Any more, and power is lost and distortion results when the wick is turned up to compensate...........
( Great fun changing the air-gap while powered up and the Tx throbbing at 15Hz....................!)
Running Square waves, with F/B, at 100 Hz, looks good, with around 1V droop at 20VP-P
Running 1KHz the square is good.
running 10KHz shows very slight rounding at the start of the horizontal top, clean at the bottom
Running 30KHz, a definate rounding at the corners of the square are visible.
By 40KHz, a well rounded square wave results.
At 100KHz, a sine-wave results.--All at max design power of 20W.
Ive gone back to my Nuvistor as the first gain-stage--I just like the sound better! (ECC91 in above diagram)
Im quite happy with the results, and my next stage is to build the final amp...........................
Ive tried a few experiments with the air-gap and find that I get higher O/P and less distortion running a gap of .11mm as opposed to my original .22mm
I can now get a pretty respectable sine-wave at 15Hz, at 20W. Any less air-gap and saturation causes distortion ,Any more, and power is lost and distortion results when the wick is turned up to compensate...........
( Great fun changing the air-gap while powered up and the Tx throbbing at 15Hz....................!)
Running Square waves, with F/B, at 100 Hz, looks good, with around 1V droop at 20VP-P
Running 1KHz the square is good.
running 10KHz shows very slight rounding at the start of the horizontal top, clean at the bottom
Running 30KHz, a definate rounding at the corners of the square are visible.
By 40KHz, a well rounded square wave results.
At 100KHz, a sine-wave results.--All at max design power of 20W.
Ive gone back to my Nuvistor as the first gain-stage--I just like the sound better! (ECC91 in above diagram)
Im quite happy with the results, and my next stage is to build the final amp...........................
Err.... 
I guess this is my nature – I always try to get a second opinion or better yet, I try to study the topic at least so far, when I can convince myself that the solution offered is OK. It doesn’t mean it must be proved to be a "bulletproof" design but within the practical and reasonable design constraints of known compromises made during design.
The code or actually a program I have found is written based on the methods of calculating SE OPTs by one of the best Russian transformer winding experts. I know what formulas and methods this guy is using; I don’t know how Ives wrote his code.
So I just thought it would be interesting to compare the results.
I guess this is my nature – I always try to get a second opinion or better yet, I try to study the topic at least so far, when I can convince myself that the solution offered is OK. It doesn’t mean it must be proved to be a "bulletproof" design but within the practical and reasonable design constraints of known compromises made during design. The code or actually a program I have found is written based on the methods of calculating SE OPTs by one of the best Russian transformer winding experts. I know what formulas and methods this guy is using; I don’t know how Ives wrote his code.
So I just thought it would be interesting to compare the results.
Actually its is already in the Excel sheets. It's just too plain clumsy to manipulate figures in the between excel sheets IMO. A clearer interface would have been user-friendlier. Anyhow it works. I’ll try to put that into English because the comment lines are written in Russian. Until then if anybody is interested here are the links to the programs at the web page of the author.
http://charmel.chat.ru/practice/ziptext.zip
http://charmel.chat.ru/practice/zipbook.zip
http://charmel.chat.ru/practice/se_calc.html
http://charmel.chat.ru/practice/ziptext.zip
http://charmel.chat.ru/practice/zipbook.zip
http://charmel.chat.ru/practice/se_calc.html
Any news on the Russian version of the Calc?
Be interesting to see how this one compars with the original Yvesm calc Ive found so effective at making O/P Tx's
Ive been doing some more alterations to my design above.
Ive replaced the 6sn7 Mu driver with a 6J5 (close or same as half a 6sn7) single triode in the upper half of the Mu driver, and a 6SL7 in the lower half of the Mu stage. Ive set the current through the strapped (paralleled) SL7 for around 5mA, by dropping the cathode resistor to 220 ohm.
Although good before, the bass now seems more controlled, powerful and just seems somehow better. I have as yet to do proper testing in this configuration (guess the overall gain increase the SL7 is giving is increasing neg feedback I have not altered the feedback resistor) so cant yet comment on the figures..........
Be interesting to see how this one compars with the original Yvesm calc Ive found so effective at making O/P Tx's
Ive been doing some more alterations to my design above.
Ive replaced the 6sn7 Mu driver with a 6J5 (close or same as half a 6sn7) single triode in the upper half of the Mu driver, and a 6SL7 in the lower half of the Mu stage. Ive set the current through the strapped (paralleled) SL7 for around 5mA, by dropping the cathode resistor to 220 ohm.
Although good before, the bass now seems more controlled, powerful and just seems somehow better. I have as yet to do proper testing in this configuration (guess the overall gain increase the SL7 is giving is increasing neg feedback I have not altered the feedback resistor) so cant yet comment on the figures..........
Hi Jaime,
I beleive it's possible.
Here I've attached two files for the program to show how this could be done.
You may left the "secondary impedance" value blank to simulate a choke.
Of course, values computed for Leakage inductance and other associated results like Fhi, shunt cap and F0 are meaningless.
I've assumed 200mA plate current for the choke.
The OPT does not need to be gapped.
Let me know if you feel something is wrong.
Yves.
I beleive it's possible.
Here I've attached two files for the program to show how this could be done.
You may left the "secondary impedance" value blank to simulate a choke.
Of course, values computed for Leakage inductance and other associated results like Fhi, shunt cap and F0 are meaningless.
I've assumed 200mA plate current for the choke.
The OPT does not need to be gapped.
Let me know if you feel something is wrong.
Yves.
Parafeed advantages?
Not having done any parafeed type amps, I was wondering what would be the advantages of this type of layout, apart from the extra weight!.
The addition of a capacitor in the sig-path at a high current in most designs shurely cant be good for quality at higher levels of output?
Then again, what do I know--Ive never built one!--Im mad enough to make P-P amps using 811A tubes, and MOSFET drivers.............!
Not having done any parafeed type amps, I was wondering what would be the advantages of this type of layout, apart from the extra weight!.
The addition of a capacitor in the sig-path at a high current in most designs shurely cant be good for quality at higher levels of output?
Then again, what do I know--Ive never built one!--Im mad enough to make P-P amps using 811A tubes, and MOSFET drivers.............!
I have made EL34 push pull transformers (triode connexion) but always I have scared with the SET transformers with air gap.
By that reason, I followed with much interest the design of the transformer that you have done. And the reports of Alastair have excited me.
Referring to parafeed, some people say that it is possible to optimize better the inductance and the transformer in this configuration.
An article in this forum woke up my interest.
SET on a budget
http://www.diyaudio.com/forums/showthread.php?threadid=64530&highlight=
It is evident that I will have to study more.
The 6c33c-b are waiting.
best regards Jaime
By that reason, I followed with much interest the design of the transformer that you have done. And the reports of Alastair have excited me.
Referring to parafeed, some people say that it is possible to optimize better the inductance and the transformer in this configuration.
An article in this forum woke up my interest.
SET on a budget
http://www.diyaudio.com/forums/showthread.php?threadid=64530&highlight=
It is evident that I will have to study more.
The 6c33c-b are waiting.
best regards Jaime
Re: Parafeed advantages?
Well I can think of two serious advantages.
A. The otp can be designed for no dc current.This means tighter coupling and allows use of exotic (nickel?)materials that would normally saturate.
B.The ac signal is no longer coupled thru the PS electrolytics( yuck)! but thru a small high quality film parafeed cap.
Would that be interesting to you?
Alastair E said:Not having done any parafeed type amps, I was wondering what would be the advantages of this type of layout, apart from the extra weight!.
The addition of a capacitor in the sig-path at a high current in most designs shurely cant be good for quality at higher levels of output?
Then again, what do I know--Ive never built one!--Im mad enough to make P-P amps using 811A tubes, and MOSFET drivers.............!
Well I can think of two serious advantages.
A. The otp can be designed for no dc current.This means tighter coupling and allows use of exotic (nickel?)materials that would normally saturate.
B.The ac signal is no longer coupled thru the PS electrolytics( yuck)! but thru a small high quality film parafeed cap.
Would that be interesting to you?
With respect to parafeed.... You need to keep the damping under control... Basically what you have is a LCR tank circuit..... With a TRIODE you have the advantage of low R for damping...but look at the equivilent circuit and see what the Res freq is and the Q.... Somtimes you may need to add a R in parallell to the primary winding to get the Q appropriately damped...
Chris
Chris
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