MiniBurst
Sometimes you just want a quick sequence of pulses to fire every once in a while. This is where a burst generator can come in handy.
This module takes in a trigger and then fires a sequence of pulses. The number of pulses can go from 1 to 8. It is set using a rotary switch.
The speed of the pulses can be set using either an external clock input or an internal clock.
Schematic
This build is based on Ken Stone’s “Cat Girl Synth” Burst Generator as documented in the sdiy site.
It’s based around the CD4017 CMOS IC, similar to what’s found in Baby-8 sequencer. I used the extra Schmitt Trigger inverter in the CD40106 to make an internal clock normalled into the clock input.
If re-trigger switch SW2 is enabled, a new burst is started even while an existing burst is running. Otherwise, any trigger input is ignored whenever an ongoing burst is running.
PCB
My PCBs for this module were sponsored by PCBWay. Of course, everything’s open-source, so you can download all my files and modify/print them as you please.
These files will soon be available through PCBWay’s project page. You may also download all my files and print it as you please.
| Title | Filename |
|---|---|
| Gerber Files | MiniBurst v0.2 - Main.zip |
| MiniBurst v0.2 - Front.zip | |
| BOM | MiniBurst v0.2 - Bill of Materials |
| Github | https://github.com/benjiaomodular/MiniBurst |
Version Log
v0.2 - Initial release
- First working version
v0.1 - First test print
- Panel hole for button was too small.
- Wrong footprints for the ICs.
Results
Due to the simplicity of this circuit, the length and timing of the first pulse depends on the relationship of the clock to the trigger.
If the clock starts a little earlier than the trigger, the first pulse output can come out either shorter, or it may not be there at all.
If the clock starts later than the trigger, the entire burst of pulses will just start later.
Conclusion
I think this can be a good thing to integrate into a sequencer circuit, especially since it’s basically a Baby-8 sequencer that auto-resets. But that can be a project for the future.
I’ll be recording more demos if this soon. You can follow me on Instagram @benjiaomodular and YouTube.
Let me know if you’ve built it! Also, if you’d like to support what I do, please consider donating through Ko-Fi.