5V to 12V Trig Mod
Posted: Nov 14th, '16, 19:58
Hi drum machine addicts,
Since my MOTM ADSR requires at least 10V to trigger, the Nava trigger out wasn't enough, so i did a mod in order to get a 12V trigger.
The Atmega outputs a S-trig of 5V, it's then inverted by Q66, R550, R551 and R552 to get a V-trig.
The 2N3906 is powered by 5V, so I don't think it's possible to modify the existing design to get more than 5V. So I removed Q66, R550, R551 and R552, and added a little circuit on a proto-board.
I replicated what's have been done in the x0xb0x to amplify the 5V gate coming from the Atmega to 12V. It's composed of Q37, R146, R144 and R143.
This circuit invert the signal, that's why i preferred to remove the inverter in the Nava, instead it would have required another inverter (3 transistors instead of 1).
Since the x0xb0x is powered by 12V and the Nava by 15V, i put a voltage divider to get around 12V from the 15V supply with a 10k and 33k. Don't mind the 100Hz pulse on the schematic, it was just here to test the circuit
The power supply and gnd comes from the CV/Gate header near the master section. I also use it to power the second noise source i got from altitude. Since I didn't know how to attach both boards to the case (the noise one and the trig mod one), I added a switch on the proto-board to switch between original noise and second noise source for the handclap and it can be used to attach the protoboard to the case after drilling a hole. The protoboard is then attached to the second noise board with a 10mm spacer. Too bad i didn't took a picture before screwing the enclosure back, it would've been more clear haha.
Now I can modulate the filter from my modular in sync with the Nava, yeah!
I don't know if will be useful to someone since most of the modular/synths uses a 5V threshold, but i leave that here anyway.
Since my MOTM ADSR requires at least 10V to trigger, the Nava trigger out wasn't enough, so i did a mod in order to get a 12V trigger.
The Atmega outputs a S-trig of 5V, it's then inverted by Q66, R550, R551 and R552 to get a V-trig.
The 2N3906 is powered by 5V, so I don't think it's possible to modify the existing design to get more than 5V. So I removed Q66, R550, R551 and R552, and added a little circuit on a proto-board.
I replicated what's have been done in the x0xb0x to amplify the 5V gate coming from the Atmega to 12V. It's composed of Q37, R146, R144 and R143.
This circuit invert the signal, that's why i preferred to remove the inverter in the Nava, instead it would have required another inverter (3 transistors instead of 1).
Since the x0xb0x is powered by 12V and the Nava by 15V, i put a voltage divider to get around 12V from the 15V supply with a 10k and 33k. Don't mind the 100Hz pulse on the schematic, it was just here to test the circuit
The power supply and gnd comes from the CV/Gate header near the master section. I also use it to power the second noise source i got from altitude. Since I didn't know how to attach both boards to the case (the noise one and the trig mod one), I added a switch on the proto-board to switch between original noise and second noise source for the handclap and it can be used to attach the protoboard to the case after drilling a hole. The protoboard is then attached to the second noise board with a 10mm spacer. Too bad i didn't took a picture before screwing the enclosure back, it would've been more clear haha.
Now I can modulate the filter from my modular in sync with the Nava, yeah!
I don't know if will be useful to someone since most of the modular/synths uses a 5V threshold, but i leave that here anyway.