Zvex: Interesting FX... The "Probe" series that he runs has been a source of mystery for many moons - until now! Thanks to the Freestompboxes forum members (~arph and others!) who disemboweled their own probe controllers and donated them to the DIY world :-)
Here's a demo video if you've never seen one in action before:
Here is the schematic of the actual "Probe" controller, you can see that it is a series of inverters driving a simple LED driver - this LED driver is used to control an optocoupler (Also called a vactrol) which is basically a LED stuck to an LDR wrapped in black tubing. The LDR section is then used to control a parameter of an FX unit...
[Note - missing capacitor value at the base of the second transistor - 22nF]
All you need to do to build a Zvex Wah-Probe work-a-like would be to build up a Probe controller using the above schematic and connect it's control vactrol LDR in the position specified in the Wah schematic below!
There you have it, a proximity controlled wah-wah pedal - absolutely useless for that "cocked-wah" sound ;-)
Hi.
ReplyDeleteI want to know value of the cap at bass of 2nd transistor.
Please? :)
Sorry, I didn't realize I'd missed that! The missing value is 22nF :-) Enjoy!
ReplyDeletesuper THX!
ReplyDeletethanks!!
ReplyDeleteChange the number 8,9,10 to 13,11,12, vice-versa.
The rest is Ok!
Hey there, first of all cool project.
ReplyDeleteI was looking on the net for somewhere to get the '4093N' IC in the probe schematic, and couldn't find it. In fact, I couldn't find much information about it at all. All I found was an italian website that said it was a quad 2x input NAND schmitt trigger. I found the 74HC132 at http://www.jaycar.com.au and was wondering is this the same sort of device?
Much appreciated!
oops, I am a silly lad, found it *shameface*.
ReplyDeleteHi,
ReplyDeleteThanks for posting this! I built one and it's really awesome! I was wondering what values to change in the twin T filter to change the range of the wah. The current values make the wah most pronounced on lower notes on the neck. It sounds really fat, But I'm wondering if I can get a more traditional wah sounds out of this circuit. I did try replacing the 33k resistor with a pot, but this didn't cause a big enough change to get em into the range I was looking for.
Tanks again!
Hi Everyone!
ReplyDeleteWhat does it means:Change the number 8,9,10 to 13,11,12, vice-versa.
What the difference ?
Did someone found values of parts for making sound closer to traditional wah?
I did my circuit, with sound like i got now - i will not change my moded CryBaby for that Hard KuaK.
kinda late, but is there any reason why the circuit would get noisy as i get close to the antenna? it sounds almost like a ring modulator when close, and the noise cuts out if my hand touches it.
ReplyDeleteHi, what antenna have you used?
ReplyDeletehi, is there a vero / stripboard layout of this schematic somewhere online?
ReplyDeleteI made a kind of messy layout for the proximity-control only. If you need the complete layout with the wah-circuit I can do it as well. Just let me know where you want me to send the layout-files.
DeleteDid you ever get this laid out? Having an issue where the led is only acting in an "on-Off" manner when I am very close to my antenna. Tried multiple antenna sizes and can't get it to act variably. Any help would be greatly appeciated!
DeleteThey has come a very long way in just over bbva branch near me
ReplyDeletelet's keep it growing and really make it the best uncensored.