I have wrote my opinion even if myself everytime I am on lab a lot of measurement are done.
I have hundreds of results sitting on dozen of folder that I forgot.
Same for lab of Audioreview magazine ( more powerful than mine) the variation from standard test are normal
The paper of trobbins is fine and I understood that are three OT involved.
waltube,
My post was an affirmation and a compliment; I hope you understood.
At one time, I had the good fortune to use a $50,000 R&S VNA, and $10,000 precision cal kit.
There was probably an order of magnitude or two more power in the processor, math, and processor than all the computers on the moon shot crafts.
I did lots of tests: interstage and output transformers; complete power amplifiers; components, and marketeer's favorite $$$-maker item, the speaker cables. I did the research to prove the methods and results.
My post was an affirmation and a compliment; I hope you understood.
At one time, I had the good fortune to use a $50,000 R&S VNA, and $10,000 precision cal kit.
There was probably an order of magnitude or two more power in the processor, math, and processor than all the computers on the moon shot crafts.
I did lots of tests: interstage and output transformers; complete power amplifiers; components, and marketeer's favorite $$$-maker item, the speaker cables. I did the research to prove the methods and results.
Look for something with Rdc lower then 10 Ohm And about 0dB at 20Hz at full power
Hi
One question related to your tests.
You have a test setup that's is working. Why you don't try to check the reverse method ?
Walter, why should I test transformers by the reverse method? You say transformers are bidirectional devices, but I use them one way only.
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In Italy, as you know, there is Audioreview, on nr. 385 and 392 there are the informations about the reverse method.
Written by Fabrizio Montanucci and some project by me.
The main issue of the OT test is the limited swing of signal you can have with the 100% of the generator driving the primary.
So you don't have a complete view of the real performances of the OT only ( outside of the power stage) that is not only the frequency response.
The start point of the reverse test is from this relation:
that is "coefficent of coupling" coefficente di accoppiamento.
Where M is coefficent of mutual indictance between coils
L1 and L2 the inductance of coils.
In the perfect trafo it is 1 that means a perfect coupling.
In the real world it is close to 1.
There are some paper in italian
And also, of course, in english with the mathematics ( I am not so in deep with some equations)
Where this relation is explained in deep
On AR 385 there is this article: "Trasformatori di uscita in filo Litz e come misurarne le prestazioni"; on AR 392 this one: "Trasformatori di uscita per single ended. Prestazioni a confronto". Both articles by Fabrizio Montanucci. Are the two reviews I should buy to get all the infos on the reverse method? Mathematics too?
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Hi
send me a private message.
In every case if you send an email to Audioreview they can help to get the numbers.
Mauro Neri is the director, he is my friend same as Fabrizio,
In those articles is not listed the mathematics.
But the documents around this concept is easy to find also in italian
Walter, I do not spend money in italian audio magazines, I do not spend time to contact italian newsagents. My private mail is open for scans of that articles, if you wanna send something. But you say there is no maths and I do not understand the scope of the "paper".
The reverse method has been described by you, if I'll find some time to test I do. But at present I prefer to measure them in the standard poor's old mode. As I already wrote, audio output transformer is one way use mode device.
The reverse method has been described by you, if I'll find some time to test I do. But at present I prefer to measure them in the standard poor's old mode. As I already wrote, audio output transformer is one way use mode device.
I don't want to send you a copy of those articles.
The scope of the paper is to show the method in details with test lab.
And from the last phrase I think you haven't understood the basic concept of every transformer
The scope of the paper is to show the method in details with test lab.
And from the last phrase I think you haven't understood the basic concept of every transformer
If this is your starting point then there is no need for a reverse method. Moreover, the Fiat transformers are not well made (no good high frequency response and no good sqw). You need better transformers to better understand the problem.
I personally think that a (not yours) reverse method may have some advantages (read easier to do). It requires a lot more measurements at different impedances and in many situations you only prove that the source is the problem
Maybe you can learn something good.
Your nick told something to me, then I have read some your post-
You need to learn a lot
And, remember, that Audioreview magazine born in 1981 from some people cames from Suono. In this long time developped a lot of technical article ( unfortunately only in italian) around many arguments.
So your contempt on the italian magazine is not elegant and whitout reason.
Why don't you come up with some good arguments with a solid rationale?
So far you've only presented a concept which contains obvious errors and or misconceptions. These have been named by various people AND proven by either measurements or theory.
p.s and you are a liar (I never did a measurement with a source of 80mV and you can not proof that i am wrong about that)
As you want
I don't like to have a discussion with you
You aren't able to understand and I am waiting to see your beautiful stuff ( without a black label on brand, maybe aren't yours?)
I don't like to have a discussion with you
You aren't able to understand and I am waiting to see your beautiful stuff ( without a black label on brand, maybe aren't yours?)
And again, no arguments. It has nothing to do with I like you or I don't like you, but no bullXhit here or lies.
Walter, about AR... how many copies they print monthly? The real numbers, please.
???
The contents are important.
It is evident that the numbers are different form 20 years ago but the quality of the technical articles are the same.
A lot of arguments were involved.
Fabrizio developped the sw for loudspeaker that is one of the best available in the world. (unfortunately it is only in italian)
Every time there is a stuff with interesting solution there is a explanation of the circuit with relatives test.
You don't know anything about the story of Audio and you are asking the numbers of copy?
It is a joke?
Before wrote sentences, study.
Ciao