ESL Step Up Transformers

[mstejic]

I posted earlier in the "Parts" forum, but this is probably a more appropriate place for this thread. I wanted to see if there is any interest in toroidal ESL step up transformers. I have more than I will need for my projects.

These potted transformers replicate the Final 0.3 transformer design. I have had very good success with them. Following are characteristics of this transformer:

Turns Ratio = 1:70:70 (1:140 overall)
Primary Inductance = 1.0 mH (min)

Primary Wires: Red, Black
Secondary Wires: Blue, Yellow (neutral), White

Dimensions = 3.25" (d), 2.25" (h)

Resistances:

Red:Black = .705 ohms (nominal)
Blue:Yellow = 85 ohms (nominal)
Yellow:White = 85 ohms (nominal)
​

Leakage Inductance:

Red:Black = 5.0 uH (max)
Blue:White = short
​

A schematic diagram as well as a picture is attached to this post showing what the transformer looks like.

As I mentioned, I have enough of these transformers to support a number of other projects, provided you don't require production volumes ;-)

Milan

 

[mstejic]

Example ESL Using these Transformers

The speaker in the middle is a hybrid ESL system that was designed using the transformers described in this thread. The speakers to the left and right are earlier experiments.

Yes, you can design real speakers with these transformers

 

[EUVL]

Interwinding capacitances ?
How much per pair ?


Patrick

 

[mstejic]

I'm not sure I have the correct characterization for interwinding capacitance. I don't want to steer you wrong. I will send you some additional information shortly after I've had a chance to review the specification information I have.