Build Your Own Clone Message Board

Hi

First things first, I'm total noob in this field...

I'm having a noise problem with the Analog Vibrato I just built. It's like a constant hiss/white noise ish noise when I turn on the pedal. It also seems to make the guitar signal brighter, which I a bit odd because I think it's really supposed to make it less bright..?
When I turn the internal bias trim pot all the way counter clockwise, the signal (and the noise) is gone. When I turn it back up, the signal and noise reappears around 10 o'clock, and increases until around 2 o'clock, before it kind of pops and then dies again.
I have tried different power supplies and 9V batteries, but the problem is the same.

Also, the ramp function does not work. When ramp is ON, there is no vibrato, and nothing happens when I press the foot switch

Any ideas what I've done wrong?

I would recommend the following actions to be taken in the order shown:

• Check for visually obvious errors first. Make sure the IC's are in their proper locations and are correctly oriented. Confirm that you haven't switched any of the 3904 and 3906 transistor positions. Check the values of all of the resistors and caps vs. the instruction diagrams. Your wiring and transistor & diode orientations all appear correct.
• If all that checks out, I would recommend applying THIS PROCEDURE next. It's a bit time-consuming and tedious, but the fact is that solder joint issues are by far the most common cause of pedal problems and this simple procedure is amazingly effective at resolving them.
• If the pedal is still misbehaving, I would recommend getting a set of DC pin voltages on all five IC's and report them here. I can provide further details on how to do that, should you need them.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Hi, and thank you for your help!

I finally found the time to do some troubleshooting.
I went through all of the components and compared it to the instructions, and found that I had misplaced two resistors, or so I thought at least.
Turns out, when I removed the resistors, I had placed them correctly according to the markings on the PCB. So apparently there is some mismatch between the instructions and the PCB markings. See pictures
I swapped the resistors around anyway just to test, but the noise problem is exactly the same.
So which is correct, the instructions or the PCB?

I also went ahead and reflowed all of the solder joints, and now the ramp function is working.
So the only problem left is the noise.

Any ideas?

Thank you again for your help so far!

The PCB silkscreen is correct for those two resistors.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Ok, thanks.

Could you please provide further details on how to do step 3 in your first reply?

Sure. To measure the DC voltage level on the IC pins, set your multimeter to the DC voltage mode, indicated by a solid line above a dotted one. Use the 20VDC range setting if it's not an auto-ranging meter. Your power source needs to be connected and there needs to be a cable in the input jack. Set the pedal's depth and rate controls to their midpoints. If the pedal is assembled into the metal enclosure, put the black probe into one of the corner screw bosses of the enclosure--this is your ground connection. If the "guts" are out of the enclosure, use the sleeve tab of the input jack for the ground connection. Then touch the red probe to each point that you want to measure. See image below for the numbering of the pins. Post your results here for review.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Here are the results.

Need the pin voltages on the 6110 IC also. Sorry, should have mentioned that. The #1 pin is at the left end (square solder pad).

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Here it is.

One thing to note about pin #4. It startet around 060.0, but then slowly crept up towards 090.0.

OK, a lot of your voltages look good, but the problem seems to be that you're not seeing the voltage modulation that should be present on a lot of the pins, specifically:

6110: pins 6, 7 & 8
3102: pins 2, 4 & 7
3207: pins 2 & 6

The LFO seems to be working since pin 7 of the TL022 IC is modulating. My best guess is that the BA6110 is faulty, since it precedes the 3102 & 3207 in the circuit. Not sure if you can get a replacement at this point from BYOC, but you can try them at sales@buildyourownclone.com. That IC is available elsewhere, however.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2