Iron Pre Essentials Kits For The DIYA Store- Register Your Interest

Joined 2010
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My wife doesn't like my driving.... I'd rather not know where we're going. I need another beer.

The great thing about being in the caboose is that I can kick back and smoke a cigar and none of the big shots up front complain about the smoke.


What's very interesting is that DC is blocked. The electric field is a function of the change of the magnetic field. And


...the same... note the permeability of free space ( mu zero ).... I imagine this is where we'd plug in the core's permeability.. which shows that iron creates a much stronger magnetic field than air from a given electric field... ( current in this case ).

Remember to use the right hand rule! It's so British... counterclockwise.

So we want a core with a high permeability and windings with high conductivity ( low resistance ) to make the most efficient transformers. All other factors being equal, of course.
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Are there any differences how the jfets are matched between 2 x SE kits vs 1 x balanced kit?
Are the jfets pairs matched like 4 x quads for the balanced kit? that would be the main difference? .....apart from getting an extra set of Cinemags if 2 x SE kits are purchased?
Joined 2019
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@MEPER - Too late to edit above. I was thinking more about your question. Are you just asking about JFET matching, or are you asking if you could purchase two SE kits and make a balanced?

If it's the latter... I'd go with no; not without an amount of effort that would likely make it not worth it (at least for me).

So... for clarity... My first sentence would be...

No difference from SE to Balanced in the way that the JFETs are matched.
Official Court Jester
Joined 2003
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Ok, yes I had the idea of getting 2 x SE kits to make the balanced version. But then I was thinking about the JFET matching if those where special matched for the balanced kit. I have not yet invested time looking at the PCBs.....SE vs. BAL.

that would be $hity Bal

think - what's difference between two independent antiphase SE (working "together") and one proper differential?
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