Phase 90 not phasing

Started by Sody54, June 20, 2007, 03:23:41 PM

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Sody54

Well, I was going to try and have the first pedal related post..oh well...

I've got my phase 90 up and running.  I seems to have a problem somewhere though.  The only phasing I can get out of it is when I adjust the trim pot.  It won't do it on it's own.   I had to make a couple of substitutions on my build.  First was the 5.1 zener.  The closest I had was a 6.2.  The second was the 4125, I used a 3906.  I also used J201's.   

Any ideas out there in this fresh new landscape?

Thanks

Toney

#1
 Try a lower Zener/ test the Fets for a low voltage matched group...the trick is getting a 'em with Vgs(off) of  less that 3v.
I think the original Zeners were more like 3.3v..so yeah, I'd definitely start there.

Sody54

Thanks, I'll try that.  I used the 6.2V because it was the lowest one I had.  Guess I need to go find some more.....Have to build me an FET tester now too I guess. 

Thanks for the tips.


KarenColumbo

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jimilee

Are the j201s matched? I'm interested to see if you can get it working. Those are a considerably higher output tranny the 5457s or the 5952s.