Author Topic: Supreaux Deux Faux Pas  (Read 4453 times)

dropanchor812

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Re: Supreaux Deux Faux Pas
« Reply #15 on: July 30, 2013, 09:00:50 PM »
And here's another pic that wouldn't fit in the last post.

FYI - they look all scratchy between a bunch of the pads because I was looking for bridges. 
« Last Edit: July 30, 2013, 09:02:52 PM by dropanchor812 »
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dropanchor812

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Re: Supreaux Deux Faux Pas
« Reply #16 on: July 31, 2013, 05:15:07 AM »
4.  Checked voltages of all the transistor pins.  They are as follows - (Read D-S-G)
 Q1 - 8.26 - 0.56 - 0
 Q2 - 11.91 - 0.33 - 0
 Q3 - 11.26 - 0.56 - 0

Good morning!  Alright, so I was looking at the schem and trying to do some research on reading voltages.  It makes sense that the Drain reading is near 12v because that's the part of the transistor that was getting biased with the trimmer (I think Q1 got moved after biasing).  The source and gate I am having a little more trouble completely understanding.  Source goes to a pull-down resistor, right?  And then we have no voltage coming into the transistor from whatever is before it in the signal path.  Am I properly understanding how the transistors are working?  If so, I would figure I should be getting at least some reading from the Gate pin.

When I took these voltages I didn't run a signal through the circuit while I was doing it.  I don't think I was supposed to, but just wanted to throw that out there in case it mattered.
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dropanchor812

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Re: Supreaux Deux Faux Pas
« Reply #17 on: July 31, 2013, 12:11:36 PM »
Alright, with a little consultation from diablochris6 I did some more testing on this.  He showed me how to test continuity with our dinky DMMs and I did not get any readings between R1 and R2.  I'm not sure which side of R1 goes to ground, but I tested both sides anyways to both sides of R2 in every combination possible and I got nothing.  As I said earlier, I'm only getting a squeal when I probe both sides of R2 with my audio probe... so does this mean there's something wrong with the connection between R1 and R2?
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midwayfair

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Re: Supreaux Deux Faux Pas
« Reply #18 on: July 31, 2013, 12:31:35 PM »
so does this mean there's something wrong with the connection between R1 and R2?

not necessarily, but it does mean you need to make that connection. Just run a clipped lead between them.

If you're not sure which side of R1 connects to ground ... test for continuity to ground.
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dropanchor812

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Re: Supreaux Deux Faux Pas FIXED!!!
« Reply #19 on: July 31, 2013, 08:57:03 PM »
Looks like it was the connection between r1 and r2 because it works now!  Right now it's alligator clipped, but I need to make it permanent.  I'm just going to use a jumper wire because I think trying to solder ridge it could get messy.  Thanks everyone for the help, and I promise to change out C8 one of these days.  Thanks!!!
« Last Edit: July 31, 2013, 08:58:36 PM by dropanchor812 »
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