Klon Clone pedal help Klon Clone pedal help - diyAudio
Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Instruments and Amps Everything that makes music, Especially including instrument amps.

Klon Clone pedal help
Klon Clone pedal help
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 4th January 2013, 10:45 PM   #1
tom42107 is offline tom42107  United States
Account disabled at member's request
Join Date: Feb 2010
Default Klon Clone pedal help

I built this pedal for my son for a Christmas present and it doesn't work. I've included the schematic, layout and picture. It does not pass audio and it has a oscillating, chirp type sound when I turn up the gain knob. I've checked the IC pin voltages and noticed IC2 pins 1 and 7 are to low. These are the output pins of the TL072. I'm using a 9vdc, 300mA wall wart and the voltage unloaded is 13.6vdc. Here are the IC pin voltges:

1 - 6.02
2 - 6.02
3 - 4.66
4 - 1mV
5 - 6.03
6 - 6.04
7 - 6.04
8 - 12.17

1 - 2.2
2 - 5.75
3 - 6.06
4 - (-11.7)
5 - 6.04
6 - 6.04
7 - 3.8mV
8 - 22.3

1 - 12.6
2 - 5.89
3 - 1.8mV
4 - (-5.96)
5 - (-11.68)
6 - 7.61
7 - 10.09
8 - 12.16

Here is a link to another build and the correct pin voltages:
freestompboxes.org • Login

This is my first vero board build. There were quite a few trace cuts but I've double checked with my DMM that they were correct. I've also double checked component placement and orientation, but I'm going to check again. If someone has the time to look this over and maybe have an idea about what I did wrong it would be much appreciated. Thanks.

Attached Images
File Type: jpg Klon.jpg (363.5 KB, 38 views)
File Type: jpg klon_layout.jpg (200.1 KB, 38 views)
File Type: jpg KlonCentaur-5-24-08b.jpg (248.3 KB, 40 views)
  Reply With Quote
Old 6th January 2013, 03:51 AM   #2
tom42107 is offline tom42107  United States
Account disabled at member's request
Join Date: Feb 2010
Well, I've taken out IC2 and all the voltages seem to be right. I've replaced IC2 TL072 with three different ones and I still get low voltage readings on pins 1 and 7. I've checked all the voltages, +V, -V, +V2 and +Vb coming out of the 7660 and up to IC2 and they seem right. I just tried turning all the pots fully open, CW, and the voltage readings on both IC1 and 2 are just jumping all over the place. When I remove IC2 with the pots fully CW the voltages are stable.


Last edited by tom42107; 6th January 2013 at 03:53 AM.
  Reply With Quote
Old 7th January 2013, 09:52 AM   #3
Tesla88 is offline Tesla88  Italy
diyAudio Member
Tesla88's Avatar
Join Date: Dec 2011
Location: Italy
Hi , can you post voltages referred to GND of +V, -V, +V2 , +Vb ...
Something strange with design ,assuming a 9Vdc regulated supply then:
V+ should be +9V
V+b 4,5V
V- at -9V
V+2 at 18V
So , IC1 supply by single voltage at 9Vdc so is right biasing the non inverting input at middle voltage from Vb ..
Ic2 supply is +18(pin8) and - 9 (pin4) ... and the bias is at 4.5V , how can this work?

IMHO you can supply IC2 from +18(v+2) and GND and put bias at V+ (9V) or (better solution)supply IC2 by + 9V and - 9V and bias to GND ...

Really don't get sense about that circuit design , bad traced or work bad, and the fact so many on freestomp boxes post bad results made me thinking...

Anyway check voltages and post results . Check also connections to the double pot used for GAIN , since it's double a wiring error can occour
Also try don't use that kind of wires ,too much capacitive coupling between wires ,use single wires is better and shielded wires for input and ouput...

P.S: Stupid question...do you plug something at input during test? an open input is always a bad thing for test , plug an instrument with volume at 0 muted or a dummy plug (10k for example) or a shorting plug ...

Happy New Year
  Reply With Quote
Old 7th January 2013, 01:38 PM   #4
tom42107 is offline tom42107  United States
Account disabled at member's request
Join Date: Feb 2010
Thanks Tesla88, I get to that as soon as I get home from work. Just wanted to say that there have also been quite a few people that have built this and it worked from the start. I'm pretty careful about my wiring but I will definitely change type of wire and then re-measure voltages, with a dummy load input.

  Reply With Quote


Klon Clone pedal helpHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
3 channel all tube preamp pedal w/fx loops for all clone build jamhard Instruments and Amps 0 2nd June 2011 11:22 PM
Hello to all the pedal makers.... bloodmoon Introductions 1 29th September 2008 04:01 PM
Guitar Pedal Glowin Plates Instruments and Amps 7 9th March 2005 05:16 AM
DIY Pedal Dwiel Instruments and Amps 1 17th September 2004 11:27 AM
Question regarding ProAc 2.5 Clone and Tempo 2 Clone zoooh Multi-Way 5 11th March 2003 08:19 PM

New To Site? Need Help?

All times are GMT. The time now is 02:58 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio