e-licktronic Forum

Hello,

When measuring with a scope on R44 and R45 as described in the building tutorial i can't get a square wave.
The waveform looks more like a 'spike' as shown here. I resoldered the area around the schmitt trigger and checked values of all components around it. Everything seems fine. Does anybody have an idea on where to look or what might be causing this? Any help would be much appreciated!

Tom

Hey Tom,

I have a very similar problem the output on my oscilloscope is exactly the same. Also the pitch of my Cowbell is way too low, changing R44 & R45 does not have much effect on the pitch.

I have a replacement Schmitt Trigger IC to try out, just need the time to install it. I’ll let you know if this has any effect.

Thanks for taking the time to reply! Curious to know what you will find...
In the meantime i'll just continue the build...

lfo2vco wrote:Hey Tom,

I have a very similar problem the output on my oscilloscope is exactly the same. Also the pitch of my Cowbell is way too low, changing R44 & R45 does not have much effect on the pitch.

I have a replacement Schmitt Trigger IC to try out, just need the time to install it. I’ll let you know if this has any effect.

Thanks for the reply in other thread, if you manage to get it sorted please report back so I can advise my mate what needs doing, I'm not sure if both osc's are out TM1 and TM2 or it is just one, TM2 goes higher pitched but I'm on/near the limit of tuning clockwise, then TM1 is anti clockwise until harmoninsing(tried detuning TM2 as well), I tried the Scope software but I am getting two lines red/green and do not know what I am doing, so had a looped original 808 cowbell taken from Wave Alchemy TR Revolution to try and tune to, but that seems like an octave higher overall, well alot higher in pitch than what I can can get.

Everything else sounds spot on, but this is bugging me

Hi Seven,

Indeed I hope to check the Schmitt Trigger IC very soon, and I’ll report the results ASAP.

If you are using Audio Explorer as your scope the red and green lines show the right and left channels. You can select one or the other channel from the menu (sorry can’t recall which one as I am away from my home computer).

lfo2vco wrote:Hi Seven,

Indeed I hope to check the Schmitt Trigger IC very soon, and I’ll report the results ASAP.

If you are using Audio Explorer as your scope the red and green lines show the right and left channels. You can select one or the other channel from the menu (sorry can’t recall which one as I am away from my home computer).

thanks appreciate it

OK, so I swapped out U1 4584N for another generic Hex Schmitt Trigger and it made absolutely no difference
Both the pitch and the image on the scope were exactly the same as before.

So I guess the problem lies elsewhere.

Thanks for trying lfo2vco! Vincent or anyone else from e-licktronic, any ideas as to what may be causing this? Not getting a square wave in the cymbal section when checking with a scope and possibly related the low pitch of the cowbell? A few people seem to have this problem. Thanks!

Tom Dee wrote:Thanks for trying lfo2vco! Vincent or anyone else from e-licktronic, any ideas as to what may be causing this? Not getting a square wave in the cymbal section when checking with a scope and possibly related the low pitch of the cowbell? A few people seem to have this problem. Thanks!

OK, I am not into understanding how to do the 'scope' thing, but just went in an loaded a Wave Alchemy Transisitor Revolution Cymbal into cubase with a Yocto pattern featuring a cymbal,

I didn't notice before, but that is a different pitch too, it is lower sounding, not alot but lower than the sample.

However as a Cymbal in it's own right it sounds correct, does this help the situation, i.e. it something that 'could' be related to both cymbal and cowbell?

Tom Dee wrote:Thanks for trying lfo2vco! Vincent or anyone else from e-licktronic, any ideas as to what may be causing this? Not getting a square wave in the cymbal section when checking with a scope and possibly related the low pitch of the cowbell? A few people seem to have this problem. Thanks!

Vincent stopped by tonight and answered my other thread but did not visit here, does he only check brand new threads?