[SOLVED]Boneyard Oscillation / Whine Problem

[andrapgm03]

Hey friends,

After I've built glitterratti, I tried to built Boneyard "Modified"  (Carl martin Plexitone as listed in http://www.madbeanpedals.com/projects/Boneyard/docs/Boneyard.pdf) and It was great sound. I followed all the Boneyard.pdf, including 47 Ohms Resistor value, 151pF,etc.

I have a quick question, that some of MB members have faced down, pretty sure, I also on the same boat with them, but mine, quite weird.

The Problem
I came up with ICL 7660 for the IC2 and LF347 for the IC1, seems ICL 7660 works for this project, but I got a whine sound or some of members here called oscillation when I turned up the tone pot from my Guitar, about 50 to 100 percent of tone, then I tried to lower it down, and turned up my guitar volume to full knob, I still got the whine, and also when I turned down the guitar volume until 50%.

My thoughts about this issue
After several discussion with my close friend who have been built some several pedals, he said first try is to give the INPUT and OUTPUT jack a shielded cable, so it will reduce hi-gain frequency.

If it's not give any differences, so I tried to put 1K resistor near between INPUT lug and GROUND lug at ON/OFF 3PDT

My friend also told to me lower the caps value from the ICL7660 or change into MAX1044 (as it mentioned in pdf)

My questions
1) Will the shielded cable kill the whine / oscillation of my boneyard ? If it does, then I will do it
2) What should I do to kill the whine problem between my boneyard and guitar volume/tone problem ?
3) Will Boneyard wipe the whine if I change the ICL7660 into MAX1044 ?
4) Do you have some other ideas not listed here? Please tell me

Thank you

Pics


422812_10150573746782775_714997774_9329677_1168231226_n by andrapgm03, on Flickr


420946_10150573745507775_714997774_9329673_782583577_n by andrapgm03, on Flickr


425241_10150573744072775_714997774_9329668_845223686_n by andrapgm03, on Flickr


409504_10150573738497775_714997774_9329628_1201578178_n by andrapgm03, on Flickr


398744_10150573744712775_714997774_9329671_1298984559_n by andrapgm03, on Flickr

[andrapgm03]

Yeayyyy, Finally, I have solved this problem, with a lot of consideration to added some Resistor value to 3PDT.

I will assume that Modified Boneyard will create an oscillation, also happened with mine.

What I have done to kill Boneyard Oscillation are:

1) Add shielding cable into INPUT and OUTPUT jacks
2) Add 1K resistor value between 3PDT INPUT and GROUND lugs.

These are work out with Modified Boneyard, I've found this after several debugging with this pedal all day.

Another simple resolution with these pedal (if you don't want to add 1k value or shielding cable) is put the Boneyard after DS1 (BOSS) or some OD/DIST pedals with input buffer in it. This also will reduce the oscillation to my Boneyard.

There are several consideration (which become my big dilemma) to solder the 1k value or re-setup your guitar chain. I decided to solder 1k value between INPUT and GROUND lugs in my Boneyard ON/OFF 3PDT, so I have a chance to give serial stomp  box signal chain into my hi gain amps (such as mesa Dual Rectifier / JCM800). I've also found that the differences between 1K value or not using 1K value is not give different result of Plexi Tone Simulation, but I believe there are some differences in Boneyard Clipping Diodes and Volume , Tone Tweaking.


IMG_0476 by andrapgm03, on Flickr


IMG_0477 by andrapgm03, on Flickr


IMG_0478 by andrapgm03, on Flickr

so Thank you for CK, audioware, and Madbean who have written several documentation about this mods.

Notes for MB:
You can give 1K resistor value to the documentation if you want to, but remember, the volume will going to drop a bit, but it removes the oscillation. It's kind a big dilemma with this situation

[CK1]

Just saw this thread now, so sorry for the late reply.  Glad you figured something out!

My eventual solution was a compromise: I started using a line buffer on my pedal board at all times (wah first, buffer second, everything else after).  Sounds tangibly better than having my DS1 be the buffer.  I highly recommend a good line buffer no matter what your setup is, so this is a win-win as far as I'm concerned.

I may pull the Boneyard apart and try your shielding suggestion, as well.  Thanks for the good write-up!

[CrunchBerry]

Sorry to keep digging up an older thread.   

You mentioned that you added a 1k resistor and used shielded cable for the input and output.  Let me ask this question.  Do you use shielded cable from the input from the input jack through the footswitch to the PCB, then to the same for the output, from the PCB through the footswitch to the output jack?  Basically anything input or output not connected on the circuit board gets wired with shielded cable?

Also, did you connect the shield to anything (i.e. ground or case) or just simply use a cable with a shield?

Just wanted to clarify.  I added the 1k resistor and still have the whine, so I was going to try the shielded cable tonight, because I would really like to start using this pedal.  Also, I think Jacob mentioned trying a different charge pump, which is next on the list to try if this doesn't work, but I have shielded cable, but no charge pump on hand.

Thanks,
Jason

[Willybomb]

Just thanking you for the fix, but 1k is probably shunting too much signal to ground and that's why you're getting some a dramatic change in distortion levels.  Work your way up until the whine is back, I've found 150k to be pretty good, but I'm also guessing this might be dependent on how much output your pickups have.