e-licktronic Forum

Hey!
My yocto is almost ready but I'm having a kinda ringmodulated sound in these instruments. Any idea?
Thanks!

Have you checked all your solder points in the circuit to see if maybe there is short somewhere? Have you gone back through and confirmed you have the correct resistors where they belong. All caps in the right direction? Did you socket all your IC's? Did you have any parts left over when you finished the build?
The cymbal and hi hats are the worst to have a problem with because of how dense it is populated with parts. Good luck!

dasanalog wrote:Have you checked all your solder points in the circuit to see if maybe there is short somewhere? Have you gone back through and confirmed you have the correct resistors where they belong. All caps in the right direction? Did you socket all your IC's? Did you have any parts left over when you finished the build?
The cymbal and hi hats are the worst to have a problem with because of how dense it is populated with parts. Good luck!

My tech guy has been checking all the cymbal section with no changes. I guess all the resistors and caps are ok, because he has checked several times. Al the IC's have been socketed.
No way to find the issue

Sure it's the worst section to have any problem. It's plenty of components!

Dear Pauld,

Is the Close and open hit hat working well?
Could you post a capture of the oscilloscope when you probe pin 1 and 7 of U3 ?

Best regards,
e-licktronic

Hello to everyone,

I am the tech guy, here are some wave capture pics of the U3 & U1 ic.

https://drive.google.com/file/d/0B3evtv ... sp=sharing Pin1 U3
https://drive.google.com/file/d/0B3evtv ... sp=sharing Pin7 U3
https://drive.google.com/file/d/0B3evtv ... sp=sharing Pin12 U1 tp6
https://drive.google.com/file/d/0B3evtv ... sp=sharing Pin10 U1 tp7
https://drive.google.com/file/d/0B3evtv ... sp=sharing D11 anode 1
https://drive.google.com/file/d/0B3evtv ... sp=sharing D11 anode 2
https://drive.google.com/file/d/0B3evtv ... sp=sharing D12 anode 1

cheers

Dear retroamplis,

It's seem like digital noise generate by the hex inverter doesn't work properly.
Try to replace it.

Best regards,
e-licktronic

e-licktronic wrote:Dear retroamplis,

It's seem like digital noise generate by the hex inverter doesn't work properly.
Try to replace it.

Best regards,
e-licktronic

Hi e-licktronic, thanks for the advice, but I have replaced the Hex inverter with two different date codes from Hitachi and no luck, very hard to find and expensive chips by the way. Same with the CD40106 as a replacement, I get the same signals I uploaded before...I re-check 3 times the components, values and its position on the PCB and they are correct. I do not know where to look anymore.

retroamplis wrote:

e-licktronic wrote:Dear retroamplis,

It's seem like digital noise generate by the hex inverter doesn't work properly.
Try to replace it.

Best regards,
e-licktronic

Hi e-licktronic, thanks for the advice, but I have replaced the Hex inverter with two different date codes from Hitachi and no luck, very hard to find and expensive chips by the way. Same with the CD40106 as a replacement, I get the same signals I uploaded before...I re-check 3 times the components, values and its position on the PCB and they are correct. I do not know where to look anymore.

Anyone can help? The yocto is about to be finished but we are having this cymbal issue

I don't know if this might be related but when i was building my Yocto, i noticed that the body of VR2 (the decay pot of the Cymbal)
which is grounded was resting/touching the Base of Q19*.

Might be worth to have a look at.

ikke wrote:I don't know if this might be related but when i was building my Yocto, i noticed that the body of VR2 (the decay pot of the Cymbal)
which is grounded was resting/touching the Base of Q19*.

Might be worth to have a look at.

Already check, seems to be ok. thanks for the tip!