Hey guys. I just finished my Morning Glory clone and I can't seem to get it to work. Bypassed, my guitar is heard... I turn it on and nothing. Now... the interesting part is this: If I have the pedal on and unplug the 9v... I then strum my guitar and plug in the power back quickly, the overdriven sound is there and it works, only it fades to nothing in about a second or two. Weird, I know. In addition, if i poke the back of the board, most of the leads on the output side of it can be heard, toward the middle most of them do not make an audible sound so I'm guessing there's some kind of short, I really don't know. Any help would be appreciated. Here are the pictures:
http://tinypic.com/view.php?pic=14kzds1&s=5#.UuSuPpH0Ay4 http://tinypic.com/view.php?pic=7161c3&s=5#.UuSueZH0Ay4 http://tinypic.com/view.php?pic=2ns009y&s=5#.UuSunpH0Ay4 http://tinypic.com/view.php?pic=vd0ikk&s=5#.UuSu95H0Ay6 |
Just looked over your pics and compared to the layout, didn't see any issues. By the sounds of it, you've got a short that's affecting your power. So unfortunately there's not much more to suggest other than scoring between the tracks and reflowing the solder.
Q: Why is a drummer like a scud missile?
A: Both are offensive and inaccurate. |
yeah i did all that and still nothing :/ I really can't figure out what the heck is the matter
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Does the led behave correctly?
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Yup. Works perfectly fine. Sent from my iPhone
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In reply to this post by induction
any idea what could be wrong?
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I thought maybe the power was shorting to ground, or the power jack was bad. But if the led stays on, that rules that out.
If I had to guess, I'd say you have a dodgy ground in the circuit, but it's just a guess, at this point. Do you have a dmm? If you can measure voltages on the ic pins, that would tell us something. There are several long component legs sticking out of the back of the board. They might be shorting on something. Try clipping them shorter. Same for the wires on the footswitch and led. I doubt this is the problem, but rule it out anyway. More pictures might help. This time, get close-ups of the off-board wiring (input jack, stomp switch, pots, and toggle) from a few angles. It will still be difficult because your wires are all the same color, but maybe I'll catch something. |
Hey. Yeah I have a dmm. I've been using it to check continuity, I'm not a wizard with it. Not exactly sure how to measure the ic chip though. Any pointers on that so I can get back to you when I get home? Sent from my iPhone
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Set it to DC voltage and put the black probe on ground and then put the red probe on each pin of the ic and write down the voltage you read there.
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okay.. assuming im doing this right, I get these values:
orientation: lip/indent is facing up. 1.446 1 1.049 1.560 1.041 1.345 0 0.864 |
In reply to this post by induction
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Ok. You aren't getting enough power to the IC. The pins should read something like this:
4.5 9 4.5 4.5 4.5 4.5 0 4.5 Now take voltage readings on each side of D1. Black probe to ground, red probe to D1 anode (the side without the white stripe), then red probe to D1 cathode (the side with the white stripe.) |
I get 1 on the non-white side. And 0 on the white side Sent from my iPhone
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Now do the same check on the both sides of the current limiting resistor for the led.
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The lead connected to the LED is 1.913. The lead going to power is 1. Sent from my iPhone
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And the led is lighting up? That's only 0.2 mA. You shouldn't get light out of the led with that.
Two possibilities: 1. Maype your power adapter is bad. Unplug the adapter from the circuit but leave it plugged into the wall. Use the DMM to measure the voltage between the sleeve and the center. Do you have a fresh battery available? Any kind will do (9V, AA, AAA, C, D, whatever). Use the DMM to measure the voltage of the battery (black on one pole, red on the other). Tell me what you find. 2. Maybe you're using the DMM wrong. You're getting a lot of inconsistent readings. For example, pin 8 (top right corner) of the IC is directly connected to the cathode of D1. They should give the same voltage but you're getting 1V at pin 8 and 0V at the cathode of D1. What ground are you attaching the black probe to? Edit: You should be doing all of these measurements with the circuit engaged, by the way. |
I've been connecting the ground to either the ground of the 9v or the ground at the output jack. I try both. The LED works perfect. Nice and bright and consistent. I have my DMM set at 2 (I think it was. 2 or 4 I forget what's on the meter. But yeah, that range) Sent from my iPhone
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In reply to this post by induction
By the way man, I'd be happy to compensate you for all your help via paypal. I really really appreciate your time! Sent from my iPhone
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Ok. Maybe there's a multiplication factor with your DMM. Does it have a setting where it will just tell you the voltage difference between the probes (maybe a 1 setting)? Can you measure a battery with it so we can figure out what it's telling us?
Not necessary. Thanks, though. I do this because I enjoy it. |
Here's the link to my multi meter. not home right now, but when I get a chance, I will measure a battery.
http://www.homedepot.com/p/Commercial-Electric-Digital-Multimeter-MAS830B/202353293 |
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