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DIY Stompboxes => Building your own stompbox => Topic started by: Octavian on March 01, 2015, 12:22:10 AM

Title: Ruby Amp high pitched noise
Post by: Octavian on March 01, 2015, 12:22:10 AM
Hi All,

So I breadboarded the Ruby amp according to the spec on this page (http://www.runoffgroove.com/ruby.html) TWICE, once following the schematic at the top of the page, and one following the perfboard layout lower on the page. Both times I just get a horrible piercing tone from the speaker. The volume affects the volume of the horrible tone and the gain affects its pitch. I've tried a JRC386 and an LM386N-3, I've tried a 2N5457, a J201 and an MPF102. I tried getting rid of the entire gain section, nothing seems to work. Any ideas what could be causing this?

Help! TIA!
Title: Re: Ruby Amp high pitched noise
Post by: tubegeek on March 01, 2015, 11:31:58 AM
I had a similar problem that went away after I shielded the in and out wiring and swapped the J201 for another.

Not sure which did it - I think I did both at once.
Title: Re: Ruby Amp high pitched noise
Post by: Octavian on March 01, 2015, 12:01:09 PM
I figured it out... and feel a little dumb. My wife was talking about the DGS - Director of Graduate Studies - and I think that made me swap the Gate and Source on the transistor.... twice.

I will try some shielded wire on the in and out - might reduce the hum!