Took off the magnetic shielding and flux band from both.
It's not the gapping, as putting vice pressure on both transformers increases the measurement of each about 5% -- no change in the ratio between the transformers.
Any other suggestions before I start taking apart the core? Seems to me I'd have to take apart both transformers so I can do continued comparisons until I get to a point where they measure the same...
It's not the gapping, as putting vice pressure on both transformers increases the measurement of each about 5% -- no change in the ratio between the transformers.
Any other suggestions before I start taking apart the core? Seems to me I'd have to take apart both transformers so I can do continued comparisons until I get to a point where they measure the same...
hmmmm,
Let's try again in the morning. If both xformers meet spec... let it go. I know, it will always bother you... and one channel will always "sound" better.
Still, we should be able to explain such a difference... 20% goes with the game... 80%, something IS weird.
It might be your shield... it can't be the windings.
Let's try again in the morning. If both xformers meet spec... let it go. I know, it will always bother you... and one channel will always "sound" better.
Still, we should be able to explain such a difference... 20% goes with the game... 80%, something IS weird.
It might be your shield... it can't be the windings.
Hello,
every lamination has a strong nonlinear permeability value versus
magnetization for example:
100 Gauss 760u
1000 Gauss 2400u
10000 Gauss 2700u
16000 Gauss 5000u
So when You like to measure the inductance which the main "sees" You cannot measure with small voltage levels as you do!
Probably Your transformers don`t used equal core materials, which are with strong magnetization much more similar then with
the small (measuring) magnetization.
You can try to take out the laminations from both transformers
and put one half from transformer A to transformer B and one half from B to A
Regards
Heinz
every lamination has a strong nonlinear permeability value versus
magnetization for example:
100 Gauss 760u
1000 Gauss 2400u
10000 Gauss 2700u
16000 Gauss 5000u
So when You like to measure the inductance which the main "sees" You cannot measure with small voltage levels as you do!
Probably Your transformers don`t used equal core materials, which are with strong magnetization much more similar then with
the small (measuring) magnetization.
You can try to take out the laminations from both transformers
and put one half from transformer A to transformer B and one half from B to A
Regards
Heinz
Attachments
Yes, someone at rec.audio.tubes suggested the same thing, the cores being non-linear respect to the test signal's power level. He said the fact that both transformers draw the same mains current when unloaded is an indication nothing is basically wrong. Well, I guess I'll just leave them be, after I do a test running them overnight unloaded to see if any gets warm or fries itself.
I thank everyone for their help.
I thank everyone for their help.
Hi,
running a primary with excessive mains voltage will cause the transformer to run hot.
When you increase the voltage, with open circuit secondaries, from a low start voltage you will find the primary current increases exponentially (or similar) and once past the safe maximum operating voltage it causing a lot of wasted power and excessive core heating. I suspect the manufacturers use this to determine the primary turns vs input voltage for each core size.
Are you measuring external surface temperatures or internal (core or winding) temperatures? There will be a big difference between internal and external (although not as bad as a toroid due to the exposed core of your EI).
edit, there was a thread a year or so back that discussed this primary voltage issue and also the suggestion that you can increase the output power (VA) by increasing the copper volume on both the primary and secondary windings. i.e. more turns and/or more wire diameter. I think this was less copper loss being converted to more output.
I think they also said that increasing the primary turns decreased the mechanical noise output (a year is a long time for my memory).
running a primary with excessive mains voltage will cause the transformer to run hot.
When you increase the voltage, with open circuit secondaries, from a low start voltage you will find the primary current increases exponentially (or similar) and once past the safe maximum operating voltage it causing a lot of wasted power and excessive core heating. I suspect the manufacturers use this to determine the primary turns vs input voltage for each core size.
Are you measuring external surface temperatures or internal (core or winding) temperatures? There will be a big difference between internal and external (although not as bad as a toroid due to the exposed core of your EI).
edit, there was a thread a year or so back that discussed this primary voltage issue and also the suggestion that you can increase the output power (VA) by increasing the copper volume on both the primary and secondary windings. i.e. more turns and/or more wire diameter. I think this was less copper loss being converted to more output.
I think they also said that increasing the primary turns decreased the mechanical noise output (a year is a long time for my memory).
What does it matter, if both transformers have identical cores?jneutron said:
How should I know? As I said, I never touched the primaries; they are the original ones. And again, they are identical on both transformers.
I already answered this at least twice. Why reply if you didn't bother to read the thread?
Not paint, nail polish. I was adding them one by one after coating with nail polish, so it was still wet and would glue them to each other.poobah said:
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