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Projects => Tech Help - Projects Page => Topic started by: Meowy on December 04, 2010, 06:42:59 PM

Title: J175 (or 174 / 176) P Channel FETs
Post by: Meowy on December 04, 2010, 06:42:59 PM
I've been having great success tweaking a BS250 boost (also P Channel) and thought I would give a JFET a  try.  So I found a few J175 P Channel JFETs.

Are there any OD or boost circuits out there that use these?

Title: Re: J175 (or 174 / 176) P Channel FETs
Post by: madbean on December 04, 2010, 06:56:25 PM
I don't know of any, but I am curious to know your thoughts on what you have done with the BS250. I have a couple but have never used them for anything.
Title: Re: J175 (or 174 / 176) P Channel FETs
Post by: Meowy on December 04, 2010, 10:56:58 PM
Quote from: madbean on December 04, 2010, 06:56:25 PM
I don't know of any, but I am curious to know your thoughts on what you have done with the BS250. I have a couple but have never used them for anything.

You've probably seen the "Crackle Not OK" circuit around, which is derived from the SHO. I took that as a starting point, but i am using it with a positive ground since the BS250 is P Channel. I made a few minor component changes and I really like what I get from it - clean boost with an edge at max gain. I am also messing around with cascading them to push even harder.

Polarity aside, the BS250 is a great alternative to the BS170. They sound and feel very similar, and the 250 seems to have somewhat less noise