Re: model ignitions

pentagrid@xxxxxxxxx wrote:

With very thin wire you would find it a lot easier to work with
the small diameter and smooth surfaces of an inner HV winding.

Thin wire tends to be torn appart. Don't ask how I know! :-)
Tried it with 0.112mm (the thinnest double isolated I got). Works great!
For some strange reason, the secondary voltage increased beyond being able
to measure it. 8-/
Might be a problem with my HV-probe.


You're driving the core pretty hard (2000 AT). It's worth
checking to see if you're losing permeability.

Done. Looks good. And now, I'm also getting the 20A. The Al-value of the
core is in fact higher, so I had to reduce the primary windings.


Plot HV output against peak drive current starting with very low
currents. The HV increase should be at least 80% of the ideal linear
increase.

Couldn't do it that way, but I reduced voltage and measured the current. I'm
at about 15% off of the linear increase.

Now to less secondary windings. I'm getting above 16kV with a spark plug
connected (can't believe) and I'll verify it with less secondary windings.

OD of the coil is currently 22mm. Much slimmer than the first version
(30mm). Not much left to reduce, but maybe I get 21mm with my improving
winding-skills and better layout of the start/end of the wires.

I'll have a beer for the very kind supporters!!


Nick
--
The lowcost-DRO:
<http://www.yadro.de>
.

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