Newish effect "MayheM!" (noise 567/thing modulator/dr.Who)

[any]

I started out with Tim's "thing modulator" but since I only had a regular
LM567 it didn't work very well. After searching the forum I found the
"Dr. Who" schematic wich was a somewhat improved version of the
thing modulator and the original noise 567 by hemmo.

I included the suggested buffer (single op-amp) and it reduces
noise to the 567 when nothing is played. It still "ticks" though,
but there's no way around that other then the Cmos version of the 567.
(couldn't find it lately...)

It turned out to be a highly interactive noisemaker with a lot of
ringmod/tremelo/theremin/fuzztones.
2 switches and two pots control the following:
pot1 "speed": blends the 10uF cap for tremelo to ring mod speeds.

pot2 "freq" : also a "speed" control but becomes a frequency control when the  speed pot
is turned up high.

switch1 "LDR" : 3-way on/off/on sets the LDR in series with either the "speed" or the "freq." pot
The cool thing about this is you can set a minimum resistance with the pot so you can "tune in"
to a certain frequency wich wil can set with the LDR blocked from the light.
Also when the LDR is connected to the "speed" pot, the sweep goes up. (faster when you put your foot on it)
When the LDR is connected to "freq." the sweep goes down. (slower, or lower frequency)
pretty cool!

switch2 "starve" : My original idea was to limit current to the chip to make it quiet, but it only became louder! LOL...
This switches a 2k2 resistor in series to the 567 wich then goes al Fuzzy and loud, theremin style playing sounds really cool
like this.

Here's the PCB and parts layout, since I had no way to draw the circuit diagram...
"speed" pot is 100k lin. possibly better as 50k lin. "freq" pot is 100k lin.
"starve" is SPDT toggle, "LDR" is SPDT on/off/on 3way toggle.

The PCB is made for 300dpi print, it's actually very small and can be found here:
http://www.anyplace.nl/pics/diy/mayhem-pcb.png
Oh well, I've build it very tiny like this:



enjoy, I sure do!

[turing]

looks pretty cool. i might try and shoe horn it into my current project - a load of filters crammed into 1 big box. this could be just the thing to introduce the random factor.
just one thing though, where's this ldr? is it an optocoupler? i can't make it out from the pics. but then, my brain is very tiny indeed.

[z1]

that looks awsome!
any chance of soundsamples and vero layout? 

[any]

The LDR can be seen below the footswitch. (the tiny LED like thingy)
I've found the perfect LDR for stuff like this right here.
http://www1.nl2.conrad.com/scripts/wgate/zcop_nl2/~flNlc3Npb249UDkwX05MX0IyQzpDX0FHQVRFMDU6MDAwMC4wMGNlLjA2YjFlN2ZhJn5odHRwX2NvbnRlbnRfY2hhcnNldD1pc28tODg1OS0xJn5TdGF0ZT0xNTExNjkxODc2====
They come in a 5,5mm TO18 type metal can with a little glass lens cover on top.

I'm sure a vero layout is possible, mayebe someone will take on that challege?
If you're going to use it in a multiple effect enclosure I could be advisable to use some
sort of shielding (aluminium foil, metal cage etc...)

I'll see if I can post some soundclips in the upcoming week or so...

[Jamforthelamb]

Can anyone tell me what the part marked B250P in this layout is ?

Thanks!
JFTL

[snufkin]

i think its a transistor

[jmusser]

Do you have a schematic for this? I can figure it out from the layout, but if one exists, then I won't have to. I built both the Thing Modulator, and the Noise 567. The Thing Mod, I couldn't get to work at all using an LM567. The Noise 567 does some real weirdness, like going down in pitch in some places as you go UP the neck! I could mod it to the Mayhem to see what it's like.

[KerryF]

How can you hook up an LDR to control a pot?  Any schematics for this?

[any]

Can anyone tell me what the part marked B250P in this layout is ?

that's R.G. keens polarity protection, a B250P mosfet with a 1M resistor to ground.

How can you hook up an LDR to control a pot?  Any schematics for this?

just wire it up as you would do with a normal resistor.
If you want to use both at the same time like the MayheM (to set a maximum resistance with the pot)
hook up the LDR in parallel with the pot's connections and use a switch (SPST) to engage/disengage the LDR.

[KerryF]

Can you draw me a schematic just so I can check it out?  That would be great.

Also, were do you get them?  Does Radio Shack have them?  Small Bear?  Probably Mouser.

[dano12]

Wow, that is a very nice build! Beautifully placed in a Hammond 1590A no less. Thanks much, this is on the list to build

[any]

Wow, that is a very nice build! Beautifully placed in a Hammond 1590A no less. Thanks much, this is on the list to build

thank you very kindly sir, I am quite fond of some of your creations as well... 
I did use a special dc jack wich I had to  cut up in order to make it fit due to size constraint.
other than that no particular problems getting it in.

[orgaqualia]

I built it yesterday and I love it! Thanks for the design. It really does have a HUGE variety of tones. It dosen't want to quit oscillating even when it's been bypassed but still... it's cool. My only trouble was etching the board. I don't know why but I had lots of shorts that I had to cut and It was definatly an excercise (for me) in precision soldering, so I was pretty proud that it worked the first time. By the way I went to Lowes and got a cheap dial caliper which really helped me get it all into the box. (1590B)
Thanks again, so far this has been my fav build.
I forgot to mention the lDR. I used one described as "basic stamp accesseory" in the mouser catalog. It's just a plane jane component so I stuck it in a RadioShak LED holder and it fit perfectly. There is no lens to protect it yet but Im working on it. With the knobs set a certain way I can control the unwanted oscillation so that the box is quiet when it's off. I'm gonna have to write a song just for this effect!

[any]

I've uploaded the larger PCB layout and PnP transfer to my gallery.

http://aronnelson.com/gallery/ANY-machines

Your milage may vary on the type of XX567 that you use, I've found the NE567 to be
great sounding and responds very nicely to restricting supply voltage.
The LM567C responds less to the starve function but is cleaner sounding with a bit less bleed.
You can either omit the starve switch if it doesn't work with your particular 567, or
increase/decrease the 2k2 resistor until it gives you a good "sweetspot".

I'm also working on an enevelope gated version wich should be dead silent when not in use...

[orgaqualia]

Yah I have fantasised about envelope controll of this box, but I haven't the skills yet... I look foward to your rework and thanks again!

[MikeH]

All this talk of LDRs makes me wonder something.  Won't this pedal behave differently in different circumstances.  Like, in a dark club versus a brightly lit rehersal space.  Do you put a small lamp on your pedalboard near it so that it always has a constant light source.  I don't know much about LDR based effects...

[Tim Escobedo]

All this talk of LDRs makes me wonder something.  Won't this pedal behave differently in different circumstances. 

Yup. There's a bit of serendipity involved with any LDR controlled effect dependent on ambient light.

[any]

That's why I chose to put the LDR in parallel with the pots, it allows you to set a maximum resistance.
This way it's a bit easier to work with under different light conditions.
In this case i've used a pretty sensitive LDR with a maximum resistance of ±60k typical at full darkness.
With this design the "speed" and "freqency" share a common ground connection so you can easily
switch between controlling either of them by switching the non-common.
Further more it's very cool that the LDR reverses it's action between the two.
(with "freq" the sweep goes up with more light, with "speed" the sweep goes down with more light)