Outer Winding?

[vetmed]

While researching how to implement a voltage doubler circuit I looked at the schematic for the SEX amp (rev 1.5, 11/15/04). I notice that one end of the 160v winding is referred to as the "outer winding". Can anyone explain the significance of this? Thanks

Robert Lees

[Paul Joppa]

The high voltage winding is the last one onto the bobbin, and the last layer is the "outer winding". By using it as the center of the doubler, it is always connected to a capacitor which is grounded, so it is unable to electrostatically couple hum voltages to nearby conductors - in effect, it acts as a shield.

[vetmed]

Thanks Paul. Another related question if I may I want to use this transformer and associated doubler circuit in another project. So of course I removed the doubler part of the circuit without realizing there is a correct way to hook it up I am sure that it is explained in the manual which transformer terminals are the outer winding but although I was able to read the first few pages I can't read the rest of the CD, the reader just freezes up. So if you or some other kind soul that knows this circuit could tell me which terminals are the outer windings I'd really appreciate it.


Robert Lees

[Paul Joppa]

The old stereo SEX amp used the PT-3, which has a dual high voltage winding, which must be used exactly as in the SEX or Crack. I strongly resist any use of this transformer outside the applications which we designed for it because of the risk of shorting the high voltage windings. We have consistently refused to sell this transformer separately, or support any other uses of it.

Contact Eileen to get a replacement manual.

Contact Doc B. to see about getting a PT-7, the replacement for the PT-3.

[vetmed]

Well I figured out what goes where, not because I was able to read the CD but because I turned over the other SEX amp I have. Thanks for the explanation.

Robert Lees