Build Your Own Clone Message Board

Hi there-

So this is my first build with a PCB. I have built a 15 watt Vox style amp that went quite well, so I have soldering experience. The pub is different and I think I may have done a bad job.

When i plug it in, I have at the bypass signal of the guitar. The LED is on. However, once I hit the foot switch, I get static and no guitar signal. I looked at previous posts and I will be reflowing all solder joints. I also will probably redo some of the wiring that does not look perfect.

I did measure the DC voltage on all the IC's. Most of the numbers do not match up to other peoples numbers that I have seen on here. BTW, my charge pump is super hot as well.

So, basically, I'm new at this and I m looking for another set of experienced eyes to help me figure out what I did wrong.

Thanks to anyone who takes the time to help me out:)

Links to photos. I think these will be good enough. if not let me know

https://www.dropbox.com/s/q0htzxq5ubcmu ... .jpeg?dl=0

https://www.dropbox.com/s/9jadzh2fom5fh ... .jpeg?dl=0

Did you write down your charge pump voltages? If so, please post them here. I strongly suspect that's where the problem lies.

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

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

Yes. I did.

1) 9.55

2) 4.17

3) 6.5 mV

4) 4.67

5) 6.76

6) 7.86

7) 9.49

9.55

Bad charge pump. Contact sales@buildyourownclone.com and request a replacement at no charge.

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

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

ahh ok. thanks for the information. really appreciate you taking the time:)

Danny

Hi Again

So I received the new chip and it seems better(in other words, its not hot to the touch like the other one was). However, I still do not get any sound when the pedal is activated. Led is on, scratchy, small thunderstorm sounds when I turn the pots. But no guitar signal.

Bypass is fine

New Charge pump readings

1 - 9.62
2 - 7.5
3 - 0
4 - 9.31
5 - 7.05
6 - 8.97
7 - 9.51
8 - 7.41

I suppose I will be taking it back apart and reflowing again. Do you think it may be that a capacitor went bad when the charge pump was too hot? the crackly sounds remind me of a bad cap in an amplifier. If so, will need to remove each cap and measure it until I find the bad one? still new at troubleshooting.

Hate to say it, but that charge pump looks bad, too. With a functioning charge pump, the voltage readings on pins 4 & 5 should be NEGATIVE. Here's what I see on mine:

1: 9.46
2: 4.88
3: 0
4: -4.16
5: -8.59
6: N/C
7: N/C
8: 9.46

Pin's 6 & 7 aren't connected to anything, so the readings on those two are meaningless. But the other six pins should be reasonably close (within a few tenths of a volt) to what I've shown.

Please contact BYOC again and request another one. Be sure to tell them you've had TWO bad ones already! Also, be careful handling the new IC when it arrives. They are quite prone to ESD damage, so touch a grounded surface before handling it to make sure you've discharged any static electricity you may have picked up.

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

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

ok. I wore one of those grounded wrist things when I handled it, I was concerned about that

so there's no way something else I did wrong on the PCB would make the charge pump readings out of whack?

Not that I'm aware of. Try this: Pull the charge pump out of its socket and take a set of DC voltage readings on the socket itself. Let's make sure the voltages coming in to the IC are correct.

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

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

ok. these are from the socket only

1 - 9.62
2 - won't sit still, constantly descending number
3 - 0
4 - won't sit still, constantly descending number
5 - 9.62
6 - 0
7 - 0
8 - 7.08

You've got the 5 - 8 values reversed (see image below for pin numbering), but those results look good. My working SP shows the same thing.

I would also suggest doing a continuity test between all of the socket pins to check for a possible short underneath the socket. Only pins 1 & 8 should show continuity.

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

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

oh yeah, I messed the numbering up.

I did the continuity test and only got a signal between 1 and 8, like you said.

In that case, I don't know what else it could be but a faulty charge pump. We are seeing a LOT of them lately, even though it's been a fairly uncommon problem in the past. Don't know what the cause is, but with all the supply chain problems going on in the world these days, you have to wonder if sub-standard quality chips are being produced and shipped. I guess only time will tell.

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

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

Ok. That makes me feel better about the job I did on this thing. Again, thanks so much for your help.

Luckily I had bought two kits at once. Just completed the analog delay and it works great:) a nice confidence booster

Have a great week

Danny

The replacement charge pump that was sent you was definitely tested. please email keith@buildyourownclone.com

_________________
*patience is a virtue*

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

ok. I understand I may not get another free one. but I still need a new one. I used an ESD strap and thought that would be safe enough. perhaps it wasn't? who knows?

Hi again

Good news! I received a new charge pump chip, installed it and the pedal works:)

So thanks so much for all of your help. I do have another issue with the pedal however. I wonder if I should make it a new thread? There is a fizz type sound when I use it. mostly as the sound decays. maybe more on the lower notes as well.

I saw one thread where someone had the same problem and was told to change out the op amp chips. I happened to have a few and changed mine out and that did not do it.

any other suggestions?