Phase 90 plus 4 extra stage debug

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Phase 90 plus 4 extra stage debug

Luke51411
 built the phase 90 and the daughterboard for 4 extra stages on the main page, I posted my issue on the thread there but I think it got lost in the mix. I have confirmed the main board to be working but when I hook up the daughterboard I get no sound at all, not even noise until a string is plucked it immediately turns into an extremely loud siren and doesn't stop with string decay, it just keeps going. I've gone over my build a number of times. The ICs both have 9v at pin 8, 0 at pin 4, and half supply on the rest. I don't remember the readings on the jfets but they were consistent with the ones on the working main board. I'm thinking I must have a part in the wrong place or there is something incorrect on the layout.
 

Here is a pic of my build
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Re: Phase 90 plus 4 extra stage debug

dbat69
Hi Luke

Your link to the left of the top IC looks like it is 1 hole too low.

Edit:  Dohh, just realised that you are not using the top row - stupid me
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Re: Phase 90 plus 4 extra stage debug

Luke51411
I wish that were it. I've thought about building the rest of the phase 90 on breadboard and hooking up this board to see if it works but I wanted to run it by here first to make sure there isn't anything simple that I'm missing.
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Re: Phase 90 plus 4 extra stage debug

dbat69
Have you got any more JFETs that you coult try - use it in the main board first to check it is working, and then swap out on the daughter board to see if any of them are not working properly?
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Re: Phase 90 plus 4 extra stage debug

Luke51411
Yeah I could try that. I could probably just put these ones in the main board to see if they are working. I'll try that when I get a chance.
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Re: Phase 90 plus 4 extra stage debug

dbat69
You could also check the ICs too, just in case.  Have you tried the 072s in there?
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Re: Phase 90 plus 4 extra stage debug

Luke51411
Yeah I had 72s at first and I didn't have any more to try so I stuck 62s in there.
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Re: Phase 90 plus 4 extra stage debug

ξεναγος νεκροπολης
i can't see anything wrong in your build.
but you could post your voltages, and a photo of the back side too.
btw what are those transistors you're using? i've never saw anything like that!
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Re: Phase 90 plus 4 extra stage debug

AC_FX
In reply to this post by Luke51411
The layout has pin 1 of the topmost IC linked down to the row above the transistor drains.  Your build links pin 2.
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Re: Phase 90 plus 4 extra stage debug

Luke51411
It just looks like that in the picture, I'm not using the top row. The transistors are mmbf5457 on a fabbed adapter board I found in the shared projects on oshpark. They are the same as a 2n5457. Building them up and matching them is a bit labor intensive but they seem to be more consistent overall as well. Plus you can't beat the price!
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Re: Phase 90 plus 4 extra stage debug

IvIark
Administrator
I've got a trapped nerve and so haven't been able to concentrate on anything for any length of time, hence why I've been quiet on here recently.  But I'll check over the daughterboard layout later just to make sure everything is shown connected as required.  I always go over them before posting but mistaks still do get through sometimes so I'll let you know once I've been over it.
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Re: Phase 90 plus 4 extra stage debug

Luke51411
Thanks Mark! Hopefully I didn't come off as rude in the first post. I appreciate what you do with this site and I've built so many awesome pedals on your layouts! I just get a little impatient sometimes when things don't work I'm sure you all know how it is. When I get a chance I'll measure voltages again and post what they all are, I'm just going off of memory now. Thanks again.
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Re: Phase 90 plus 4 extra stage debug

rocket88
Administrator
In reply to this post by IvIark
IvIark wrote
I've got a trapped nerve and so haven't been able to concentrate on anything for any length of time, hence why I've been quiet on here recently.  But I'll check over the daughterboard layout later just to make sure everything is shown connected as required.  I always go over them before posting but mistaks still do get through sometimes so I'll let you know once I've been over it.
i was wondering what happened to you mark. is anything able to be done to help make it better? in any event, i hope things get better, i'm sending my get better wishes from the other side of the pond.