Quote from: d3x0r on April 28, 2014, 10:02:18 PM
that's on 2mH?  (the glare on the scale is kinda bad )

The readings are in milliHenry.

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Nitpick; the foil winding is the outside winding.... (the other coil is under it... ) also I think maybe the side /direction of that winding matters...


the outside foil should be essentially opposite the wire windings from the connecting point to the other side... the inner side should be essentially a continuation of the winding... so both the outside and inside foils are connected on the same edge relative to their gap (if it's the left side of the gap on the bottom, it's the left side of the gap on the top)

Yeah.... riiiight. We are not working with microwave gigahertz technology here.
I did get the gaps opposite one another, does that excite you at all?

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foil - coil connected to foil's - coil - foil

That's not what somebody else said. I wish you lot would make up your minds.


Anyhow, here's the completed coil, outer winding:

Quote from: TinselKoala on April 28, 2014, 10:35:34 PM
The readings are in milliHenry.
Yeah.... riiiight. We are not working with microwave gigahertz technology here.
I did get the gaps opposite one another, does that excite you at all?


That's not what somebody else said. I wish you lot would make up your minds.


Anyhow, here's the completed coil, outer winding:

ya; don't know how obvious it could be to remove the outer foil first then the first coil unwind..


I'm not sure why Ghz tech is mentioned...
I'm just saying, the current is going to flow clockwise and counterclockwise in the foil windings... so the attachment on one side of the gap or the other is going to be opposite polarity

In regards to coil turns, when Akula dismantles the coil he appears to remove off fairly equal lengths of wire with each pull. The count for the first winding is 23 lengths and 26 for the second winding.

Edit: I have now tried new software and the probe does appear to be connected.

I don't know but is not working.
In my device , primary of the transformer is 22,7 mH and secondary is 7,9-8 mH.
I used one copper foil with 2-3mm gap on start and one to the end.

The size of the gap will seriously affect the inductance, but in a flyback converter is essential to allow a quick reset of the remanence flux for the next cycle to operate without getting into saturation, which will waste a lot of energy. Without a proper gap, remanence will build over several cycles until the core goes into saturation. Current then goes way up and power thruput diminishes.

It is a balancing act between required inductance, frequency of operation, gap size etc.

Best to use a current shunt resistor 0.1 ohm in series with the inductor and observe the current ramp. Any sudden upturn at the end of the current ramp indicates saturation so either gap too small, frequency too low, or inductance too low.

Careful design of a switchmode converter requires critical adjustment of these parameters. Most designers choose an operating frequency then adjust the other parameters for best efficiency while additionally  considering the power thruput desired.

I know this is not a normal design, but it is best to study the fundamentals of flyback switchmode design to avoid much hunting in the dark, and have a better overall understanding of how the core/inductor actually functions in such a design. It is not a normal transformer action.

I'm happy to see the slot was put in the brass tube. Pushing any serious power without the slot would cause severe heating / meltdown of such an induction furnace.

Regards, Vortex1

aka ION from OverunityResearch