Hey, I build it today, but it's not working :(
I checked everything multiple times but it seems my build is similar to your layout.
The 555 timer frequencies does work but I dont have any guitar signal output. i tried a few 4558/tl072, same result.
I will have an attempt on tracing the signal, but any help/further development is helpfull!
Let me know if you found something in the layout as well! :)
I'm afraid the layout has a few errors. Pins 2 and 3 of IC 1 are mixed up, Vref pair isn't actually getting 9V, the level pot has issues. It'll take a fair bit of shuffling of components to get it right.
I'll jig the layout tonight to hopefully get you sorted while Pivetta works on correcting his.
EDIT: I was wrong about Vref sorry. Looking at the wrong 56K
EDIT EDIT: I just seen that this was your first ever layout Pivetta! Excellent effort. Great use of space.
I'm getting nuts! I changed everything to your layout. But still only the frequency signal gets through. No guitar signal output. The 555 and 4558 both work. But somehow they don't mix. Am I doing something wrong somewhere? I'll try to do my best and trace the signal with the original schematic. But I'm not that good in it :P
Just went over my layout again. It matches the schematic so either a build error or schematic error. Your guitar exits pin 7 of IC 1, thru a 10K to pin 4 of IC 2. Try probing here at least to check it it's getting this far
I'm sorry to hear about your trouble. I'll try to build it and see if it works.
To Ciaran: Thank you for spotting my error. Maybe a dumb question, but I can't get why you add a 10uF cap between G and H rows.
ehm.... yes. that is unsoldered.....
I wish I could have fresh eyes all the time :)
It's still a bit sputtery (is that an English word?), so that might be the effect. Or maybe I should try a lot of different IC's for both to see if that will get it better. But it works! Thanks so much Actually, I already got some cool sounds of it!! #happy :)
More work and play!!
Many Thanks for both of you!!
This one should be on the main site as well Pivetta!! :)
I played and tried some modding. I think I will add a on/off/on switch to two points in the circuit. Which gives it some nasty, suboctave tones and just some more tone-variation.
The volume is very interactive with the frequency pot. It isn't a real volume in my opinion. Below 2 o'clock setting there's no volume. And above it's just 'on'. But varying it together with the frequency pot gets a wider range of tones. Or noisy tones I'd better say :)
Once I finished it properly I will make a video demo. Maybe I'll even box it up very pretty :)