Bugcrusher Queston

[Greenmachine]

Hi,

Has anyone built a Bugbrand Bugcrusher using a CD40106BCN rather than a 40106N?

Trying to figure out why I'm only getting oscillation.

Thanks

Layout here:  http://la-ac.com/para/images/Bugcrusher-9v.gif

[oskar]

http://electro-music.com/forum/phpbb-files/bugcrusher_nonvoltagecontrolled_273.jpg

You mean you get a clean squarewave from the output?
Any signal gets through?
Does the rate pot work?

I don't think the type of 40106 matters.

[LucifersTrip]

I know very little about IC's, but according to a datasheet it is a Hex trigger

A Great Destroyer uses a MC14049BCP, which is a Hex buffer.
http://www.luciferstrip.com/fuzz/greatdestroyer.jpg

If you use the unbuffered version, MC14049, you will not get the crazy oscillations it is known for, but just normal distortion.

Maybe yours is the opposite situation.

[oskar]

The 40106 is just trigging the s/h and is really non critical.

I know very little about IC's, but according to a datasheet it is a Hex trigger

A Great Destroyer uses a MC14049BCP, which is a Hex buffer.
http://www.luciferstrip.com/fuzz/greatdestroyer.jpg

If you use the unbuffered version, MC14049, you will not get the crazy oscillations it is known for, but just normal distortion.

Maybe yours is the opposite situation.

Looks cool but doesn't apply to this case.

[Greenmachine]

http://electro-music.com/forum/phpbb-files/bugcrusher_nonvoltagecontrolled_273.jpg

You mean you get a clean squarewave from the output?
Any signal gets through?
Does the rate pot work?

I don't think the type of 40106 matters.

Thanks for the response.

Yes, I get guitar signal coming through.

The rate pot adjusts the pitch of the oscillation.

Is the oscillation a square wave?  No scope, but if I had to call it triangle or square wave, I suppose it'd be square simply because it's a reasonably warm and robust sound - not like some of the sawtooth sounds I think I've heard ... could be wrong though.

[oskar]

Yes, I get guitar signal coming through.

The rate pot adjusts the pitch of the oscillation.

Is the oscillation a square wave?  No scope, but if I had to call it triangle or square wave, I suppose it'd be square simply because it's a reasonably warm and robust sound - not like some of the sawtooth sounds I think I've heard ... could be wrong though.

After c2(22p) you would see a thin spike, which sounds thin, and not a squarewave. If c2 is shorted you might get what you're having. worth to check up.

[Isak]

Hi guys.

i know its an old one, but i have the same problem like Greenmachine haves (had?)
i get a VCO signal at very low volume from the bugcrusher.
i used an LF398 instead of AD781, work like a charm! but i have this VCO signal and the rate pot change the tone of it.
when the pot is all the way down there is no signal, when i start to turn it to the left a bit then the signal starts.
even if nothing is connected to the input i get signal.
i used this stripboard layout : http://electro-music.com/forum/phpbb-files/ratereducer_lf398_front_326.jpg

any help will be much appreciated.
cheers,
Isak E.

[oskar]

Hi guys.

i know its an old one, but i have the same problem like Greenmachine haves (had?)
i get a VCO signal at very low volume from the bugcrusher.

You probably should. It's a noisemaker. I'm not sure if this is the same problem Greenmachine had as he didn't give enough info and gave up.

i used an LF398 instead of AD781

That's the one I'd use...

when the pot is all the way down there is no signal

Because the frequency of the signal is now under the audible ~20Hz.

when i start to turn it to the left a bit then the signal starts.
even if nothing is connected to the input i get signal.
i used this stripboard layout : http://electro-music.com/forum/phpbb-files/ratereducer_lf398_front_326.jpg

Please post some voltages...

What voltage source do you use? Two nine volt batteries?
What does the signal go to after the bugcrusher?
Have you tried different pedals after it (as buffer)?

[Greenmachine]

Hi there,

I ended up having a bad 40106.  Sorry for not updating the thread - I do appreciate the help with the debugging. 

I actually had a couple of bad 40106's, which was why I was so stumped, but then I remembered using those chips in my guitar synth project, so I probably fried them there. 

I used two nine volts I believe.

[oskar]

Let there be noise!

So is there no square wave bleed-through without a signal at all?

I actually had a couple of bad 40106's, which was why I was so stumped

That's a classic. You pick another chip for reference and get the same result...