If like me you love your KR-55 but you are frustrated not being able to synchronize in slave mode, this post is for you!
This change is extremely simple and non-destructive (except a hole).
Do you need:
- a soldering iron
- some electronic wire (about 60 cm)
- two diodes 4148 (optional)
- a 100 Ohms resistor (optional)
- a mono 3.5mm jack
The diode and resistance are optional but recommended!
It will server to protect the circuit from the KR-55 to excessive voltages from the future entry trigger.
The input signal should ideally be at 5V. With this protection, you will have a 10V voltage fearless
Input protection circuit:
So, here’s what to do:
You need to turn on top and open the Rhythm 55
Turn it one more, remove the top. Unscrew the circuit above (nb circuit)
Remove the orange wires (small white jack) on the side. In order to fully switch the top card
Now you need to find 2 points (3 if you make mod with circuit protection):
- Pin6 of IC3 for trigger GDN
- R48 for trigger positive incoming voltage (Max. +5V)
- R38 for 5V circuit protecion
Sold wires on this this 2 or 3 points.
In my case i sold wire on the top of the board. if you want, i can sold wire on the bottom. It’s the same result but some people prefer below is “cleaner”.
Drill a hole in the back of the unit. fix the mono 3.5mm jack, then solder the wires on the jack. Or components you choose to protect your circuit.
There is little room behind, put your jack stuck to the other jack (between the two boards)
Test it! done? for sure!
Up the board from the top, close the “machine” and it’s over!