Sequencer: only 2 steps working?

[bobbletrox]

I perfed the sequencer up and connected it to a PWM perf -but something's not quite right- I can only seem to only get 2 steps working so it just sounds like a weird tremolo effect.  It sounded like I managed to get all 8 steps working briefly by gently pressing the solder side, but after reheating all the joints and making sure they were good, it still only goes 2 steps!  I gave up in frustration when the +9v wire finally broke off from all my wire jiggling and sent a loud spike through my amp.

The crazy thing is that it does cycle back and forth between steps 1 and 3...which it shouldn't be able to do by my understanding.  I just...don't...get it.

[Arno van der Heijden]

Try installing the other two 100k resistors between the cd40193 and v+.
I don't know why, but it made a difference for me....

[bobbletrox]

http://www.geofex.com/FX_images/ud-rand.gif

Do you mean the 100k resistors on the CD and -Ld pins?  Which pin is -Ld on a CD40193 anyway?  The TI pinout is slightly different than the 74C193:
http://focus.ti.com/lit/ds/symlink/cd40193b.pdf

[Arno van der Heijden]

Yes, those are the ones. Mine did the same until I connected those resistors.

The -Ld pin is # 11. Look here:

http://www.musicfromouterspace.com/analogsynth/new32x1and16x2sequencer.html

[bobbletrox]

Thanks!  

I hooked 'em up and now 4 steps work lol.  Four out of Eight ain't bad I guess.  I'll keep at it and see if I can get the others to work...

Here's what 4 steps sound like controlling a PWM: sequenced-pwm.mp3

I might post this sample on the Harmony Central effects page to see what pedals users think...because I was really just interested in the electronics side when choosing this project.

[Jason Stout]

:twisted:  I like the sample!

[mikeb]

I might post this sample on the Harmony Central effects page to see what pedals users think...

"Cool - how much?"
"When can you make one for me?"

(then you tell them a reasonable price and ask if they are REALLY interested)...

...deathly silence...



Mike

[Arno van der Heijden]

Thanks!  

I hooked 'em up and now 4 steps work lol.  Four out of Eight ain't bad I guess.  I'll keep at it and see if I can get the others to work...

Mine does all eight steps, so there's still something wrong I guess....

[LinuxMan]

Hi.

I was wondering if you still have the problem with the above layout?

The thing is your 40193 (IC2) is wired incorrectly. Move the pin #5 wire
(which is a count up timer) to pin #6 (O3). And you're there.

I did the sequencer with your layout and it works now (all 8 stages). I
changed the 47k resistor to 4.7k though. Gives me more speed...

I hope that helped... Nice redraw of a circuit btw. You could fill in the
corrections one day (100k to voltage + wrong pins) and repost the thing.

Cheers
LM