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Hi there,

Just finished building my Analog Chorus Kit. LED is working fine, and sound passes through the pedal when on and off, however there is no chorus effect. When the bias control is turned fully to the right, the sound cuts out and when it's turned fully to the left the sound of my guitar is very weak. Centre position yields the best result volume-wise.

Judging from similar posts on the forum my guess would be that I have to do a reflow, but I thought I'd post a photo first and get a second opinion.

Any help is appreciated!

The 3101 chip is inserted backwards.

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

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

I have the IC socket oriented in that direction. Already tried flipping the chip around, same outcome as before. Should I re-solder the socket to be oriented in the other direction?

The socket is merely a holder for the IC--it has no "polarity" and the notch in it is intended just as a visual cue for how the chip should be inserted, assuming that the socket was installed per the outline on the silkscreen of the PCB. But the important thing is that the IC is inserted matching that outline on the PCB. As shown in the photo you posted, it's backwards--the notch in the 3101 IC should be to the left. If it still doesn't work when oriented that way, you have a different problem.

Are you sure that you installed the 56K resistor properly on the back of the PCB, as shown on pages 11 - 13 of the instructions?

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

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

I'll try reorienting the chip again. And I believe I added the 56k resistor correctly but here are 2 photos showing it for you.

Photo number 2. Hopefully they're not too blurry for you.

Yep, that looks fine.

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

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

Just plugged it back in with the chip in the correct direction. It was EXTREMELY loud and giving off a very shrill effect, sort of feedback-like in quality. No actual chorus effect was produced. Turning the bias knob down would eliminate the feedback sound, but still no chorus, just a weak guitar sound.

I should also note that the feedback sound oscillates. The oscillations change when I adjust the rate and depth knobs as well as the bias.

https://youtu.be/nATAj8zAcQY

Here's a video of the issue I'm having.

Your LFO is going very fast. Are you able to use the speed knob to turn the oscillation down very slow? The LED should also blink very slowly....like one blink a second or less.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Turning the rate down affects the oscillations, and also makes the LED slow down as well. The link below is a video showing that happen.

https://youtu.be/3zoBRhKx6So

Still really need help with this if anyone has the time to offer some suggestions

That is amazing. On the bright side, you have the coolest space laser/ambulance pedal I've ever heard!

We can't rule out that the 3101 was not damaged by installing it the wrong way. But before we get to that, should make sure that everything else is working properly. You mentioned a weak guitar sound in an earlier post.

- Going forward, please test the pedal on its own, with no other pedals in the chain, and no other pedals connected to the same power supply.
- Remove the MN3007 and MN3101 chips from their sockets. What does the pedal do then? You should have perfectly clean buffered tone that sounds pretty much exactly the same as bypass.
- Do you have a DMM and are you able to take voltage readings?

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

Sorry for the late reply, got quite busy the past little while.

I removed the MN3007 and MN3101 chips and got a clean signal through the pedal which sounded exactly the same as my bypass tone.

And yes, I do have a DMM. I have never taken voltage readings before though. Do you want me to measure every component or just a select few?

Just the 3007 and 3101 chips for now.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Here's how to do that:

To measure the DC voltage level on 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. 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 left side of the image below for the numbering of the pins. Report your results here.

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

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

Here are my results...

3101:
1 - 8.39V
2 - 4.3V
3 - 0V
4 - 4.35V
5 - 0.30V
6 - 7.39V
7 - 2.8V
8 - 0.56V

3007:
1 - 8.4V
2 - 4.35V
3 - 4.1V
4 - 0.56V
5 - 0V
6 - 4.3V
7 - 4.15V
8 - 4.15V

The voltages on pins 7/8 of the 3007 are a bit high despite the bias voltage on pin 3 being about right. I would assume you have a bad 3007. You want to see around 4V on pin 3 and around 3.5 or 3.75V on pins 7/8, so you're not too far off. Perhaps this is why your BBD is actually producing some sort of sound, instead of no sound at all. You should contact sales@buildyourownclone.com for a new clock/BBD set.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Well that's reassuring to hear in some ways! I have sent the email. Any idea if I have may caused the damage or if it was faulty to begin with? Just curious to know any "do's" and "do not's" when handling the chips I suppose.

Putting them in backwards shouldn't damage them. We test the 3007 series chips pretty thoroughly, so they worked at some point, but they still have a relatively high failure rate compared to other semi-conductors, so they must be fairly prone to ESD (electro-static discharge). Try touching a grounded surface before handling them. It's a good habit to get into before handing any semi-conductors really.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

So I received the new chips in the mail today. I was given a new 3101 and 3007. Put them in, and still got the exact same laser gun/ambulance sound as before

Here are the voltage readings of the new chips:

3101
1 - 8.36V
2 - 4.29V
3 - 0V
4 - 4.33V
5 - 0.29V
6 - 7.45V
7 - 2.87V
8 - 0.53V

3007
1 - 8.37V
2 - 4.33V
3 - 4.09V
4 - 4.09V
5 - 0V
6 - 4.29V
7 - 3.80V
8 - 3.80V

I tested those personally and the voltages look good, so I think it's safe to assume that the BBD/Clock aren't the problem. Please remove the 3007 BBD and insert a jumper wire between pins 3 and 7. Describe the sound now and what effect turning the knobs has.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Created the jumper wire. I get one continuous tone. When turning the rate knob, a very faint and quiet high frequency oscillation can be heard that corresponds to the speed at which the rate is set to. The overlying continuous tone remains constant, however. The depth knob has no effect.

Can you still hear the noise if you remove the 3101 clock driver?

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com