SOLVED Electrovibe - Deadish?

zachlovescoffee

Active member
Howdy folks,

I'm at the testing phase of my Electrovibe build and it hasn't been an easy go. I'm not quite certain what's going on with this guy. I have no LEDs but there is power to the board. I have verified +9.25vdc at the power supply, at the board, and from + to the first diode I have continuity. I'm not great at reading schematics so I am not certain how to troubleshoot beyond what I've done so far.

I took some measurements of the LT1054 and I can only assume these are correct. I read them with the black probe "grounded" to the output jack lug.

P1: 2.3vdc
P2: 4.7vdc
P3: 0
P4: -0.005vdc
P5: 8.95vdc
P6: 1.41vdc
P7: 2.54vdc
P8: 0.15vdc

In a *weird* coincidence I somehow touched something on the board with my red probe, while my black probe was touching the ground lug of the output jack and also touching the PCB holder and the LEDs lit up. I'm not 100% certain how I did it and I wasn't really able to reproduce it. So, I figured, hey, maybe I need to actually connect these jacks to the chassis or some kind of ground. So I wired an alligator clip to the output ground lug and clipped it onto my PCB holder. No lights. Wtf.

I went over every single solder I could get to and reflowed and checked for brides. It's a pretty clean piece of work.

Other things I’m not 100% on. LEDs I wired with the anode (+) into the a-pad and cathode (-) into the k-pad. I assume that’s right?

This builds not having a completed build doc isn’t making this any easier.

Any help or troubleshooting steps would be very much appreciated!
 

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Howdy folks,

I'm at the testing phase of my Electrovibe build and it hasn't been an easy go. I'm not quite certain what's going on with this guy. I have no LEDs but there is power to the board. I have verified +9.25vdc at the power supply, at the board, and from + to the first diode I have continuity. I'm not great at reading schematics so I am not certain how to troubleshoot beyond what I've done so far.

I took some measurements of the LT1054 and I can only assume these are correct. I read them with the black probe "grounded" to the output jack lug.

P1: 2.3vdc
P2: 4.7vdc
P3: 0
P4: -0.005vdc
P5: 8.95vdc
P6: 1.41vdc
P7: 2.54vdc
P8: 0.15vdc

In a *weird* coincidence I somehow touched something on the board with my red probe, while my black probe was touching the ground lug of the output jack and also touching the PCB holder and the LEDs lit up. I'm not 100% certain how I did it and I wasn't really able to reproduce it. So, I figured, hey, maybe I need to actually connect these jacks to the chassis or some kind of ground. So I wired an alligator clip to the output ground lug and clipped it onto my PCB holder. No lights. Wtf.

I went over every single solder I could get to and reflowed and checked for brides. It's a pretty clean piece of work.

Other things I’m not 100% on. LEDs I wired with the anode (+) into the a-pad and cathode (-) into the k-pad. I assume that’s right?

This builds not having a completed build doc isn’t making this any easier.

Any help or troubleshooting steps would be very much appreciated!

putting aside the LEDs for a minute, does the circuit itself work?
 
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That's a really good question. Let me 'Socrates' you with do the input and output jacks have to be affixed to an enclosure or are they considered self grounding?

Well, the enclosure is not part of the circuit ground. It's like a shield. So to answer your question: No. it does not need to be in an enclosure to work. Although I'd make a light shield for testing outside the box and seeing if it works.

LEDs are an easy troubleshoot. If you are confident they are connected in the proper orientation, your limiting resistors may be too large. I believe these are the ones but you'll have to confirm for yourself:

Electrovibe.PNG


Verify you have power to the limiting resistors and then use a breadboard to audition 4.7k resistors with extras of the same LED you used on your board. You may need lower values.
 
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Update -- I plugged it into the amp and in bypass mode it works. I have signal from guitar to amp. When I engage the 'vibe' switch, I get a loud pop to the amp and the LED comes on but VERY low output. I still get signal but no effect. The speed switch does nothing and the LED attached to it appears to do nothing.

The bulb surrounded by the 4x optical sensors appears be operational but it's flickering and low output. Does it have to be wired in any specific way or does polarity not matter?

Here's a video

 
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Update -- I plugged it into the amp and in bypass mode it works. I have signal from guitar to amp. When I engage the 'vibe' switch, I get a loud pop to the amp and the LED comes on but VERY low output. I still get signal but no effect. The speed switch does nothing and the LED attached to it appears to do nothing.

The bulb surrounded by the 4x optical sensors appears be operational but it's flickering and low output. Does it have to be wired in any specific way or does polarity not matter?

Here's a video


Have you adjusted the gain and offset trim pots?
 
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Did anyone notice that when my thumb pressed against the lugs of the Vibe switch that the LED grew brighter? Maybe that's just coincidence. I wanted to point it out just in case.

This is a tough one to remote troubleshoot. You'll need to try and use your meter and run some checks. I would start by tracing power and getting some voltages down the line at various parts of the circuit.
 
I think we should concentrate on his voltage readings for his LT1054CP (This is a charge pump btw, not the voltage regulator, although the LT1054 does have a regulator built within it).
For example, his regulated output voltage (Pin 5) is 8.95 volts.
 
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