Quote from: verpies on October 25, 2012, 05:03:46 AM
As far as the circumferential current for a 1 layer 6 turn uncompensated winding covering the full circumference of a toroid, the ratio of the radial current to circumferential current is 6:1, so it is significant.

I was referring to the partially-wound toroid as per itsu's toroid. His windings are substantially vertical and tightly wound, so the circumferential current should be minimal I would think.

Quote from: d3x0r on October 25, 2012, 04:12:16 AM
I dunno; think you'd get as good capacitance by just spreading it out, you have plenty of space to do a 1:2 space/wire ratio around...

For example, if we have 1 continuous layer say 20 turns, then continue winding another layer that starts where the first layer left off, same wire, as the second layer windings come back towards the beginning end of the first winding, the potential difference between the first and second layer gets higher. At the end where the first layer ends and the second begins, the potential between first and second layer windings is small, like what we see throughout Poynts winding that he has shown.  So it allows multiple layers of windings while keeping capacitance equally divided and small throughout the coil as a whole.
Its like the opposite of a bifi, which increases the capacitance in the coil as a whole, but is also equally distributed.

So the question should be, is there a disadvantage to winding 2 layers, first layer starts at one end, and at the other end we continue winding a second layer back across till we reach the beginning of the first turn of the first layer? We will have multiple potential differences between first and second layer adjacent windings. Is this a hinderance for some projects, where a bifi or a windings such as Poynt has shown would be a better choice?

Interesting stuff.

Mags

@itsu

Perhaps you should choose another toroid. A good starting point is choosing the right ferrite grade for the application. See here:
http://www.ferroxcube.com/prod/assets/sfappl.pdf
Then, check at www.ferroxcube.com, at Product Info, Toroids, the part number TN10/6/4 with grade 4C65

Having more power available allows me to produce more power; but outside of the controlled peek low-current settings, my E13009's do get VERY hot.  I would think that if I could make the current signal more pure, that they wouldn't be in half-on/off operation, and not have to be disappating heat... if I layer something like a few amp high frequency transistor to power to drive drivers... would that improve the sitation? or am I just rube-goldberging something  (other than that I am...)


Other than that; I'd love to know what a DSRD result actually looks like....


I've seen them for wave sharpening, that is making square waves squarer..
Definatly reversing the diode has a different result...


The first image has a sharp ring at the start
the second image has a negative dip and a slight ringing at the end...
the third image is another direction b image.


scope ground leads open, x10, AC coupling.  yellow is on the cathode of the diode, blue is on the anode of the diode, and purple is A-B, (cathode-anode) 


Direction a is the secondary winding of the TR2(?) toroid  attached such that the high side is on the cathode side, and would have to ring down the coax first.
Direction B is with the secondary or TR2 attached with low side on the cathode side, and high side on the anode, so the first path would be through the diode.

@All,

Using the  "progressive winding" technique from poynt99 above cannot be done on a small toroid.
The inner windings are closely together, but the outer ones have space in between in which the top layer sinks.

So i made a 24 turn coil all along the circumference of the toroid OD 0.42 mm wire.
But even this coil does not show a correct inductance reading (same -0.016 uH as with shorted meter leads).


I then used a somewhat bigger (Blue) toroid and rewound the 6/12turns (0.42mm).
Measurements on this toroid are:

OD 16.6mm
ID  9.4mm
Th  6.9mm

L  6t = 173uH
L 12t = 669uH

I will be using this toroid for next experiments.

Some smaller toroid's are on order, found these on Ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=370555342978&ssPageName=ADME:L:OC:NL:3160
Initial permeability u = 7000, AL=2000


Regards Itsu