View Single Post
Old 18th May 2022, 3:17 pm   #1
Join Date: May 2005
Location: Adelaide, South Australia
Posts: 373
Default SE transformer question

I've almost finished winding 2 output transformers for a guy making a SE 2A3 stereo amp, he supplied blank bobbins only and I've wound them to his specifications - he intends to complete the transformers, connecting up the individual windings. This is a project I was contemplating myself sometime in the future so I was curious about the primary inductance and how much it changed with a DC bias, I just happened to have a stack of laminations that fitted his bobbins so I assembled the first TX with 2 sheets of photo copy paper (around 0.15mm) as a core gap, my homebuilt inductance bridge came up with a primary inductance of 67Hy, with 70mA of DC bias the inductance fell to 28Hy - this seems like a huge drop that I wasn't expecting, is anyone able to comment is this what one should expect ?
retailer is offline   Reply With Quote