Finished module in action. |
There are 7 connectors on the circuit, numbered JP1 to JP7. Moreover, I have to connect the 5V and common ground.
With the synth, I ordered the set of dedicated flat cables to ease the interconnection.
I started with Ground, 5V and all connections that were not linked to a specific connector.
Before cabling connectors. |
Pin 1 above |
I started with JP2 and JP3, as I reckoned they connected mostly to pots and jacks below the circuit and that would prove difficult if I finish with them.
All ground pins on those connectors were ignored as I chose to have a common ground from the 5V power connector.
Pin 1 below |
Thanks to the schematics from M-19, I noticed the dot indicating the first signal (red line) on the connector was sometimes above or below in the Doepfer documentation tables. I fell in the trap on my first schema.
Ongoing cabling |
Annotated schematics |
Bob checks a solder joint |
Bob managed to get some useful Quality Control time.
My first tests showed I made some minor mistakes :
- switches pins are reversed with regards to the switch handle position;
- a couple of signals were wrongfully soldered on the switch pin of the jack, instead of the tip;
- I detected one or two bad solder joints that escaped Bob's control.
Here is the finished product.
Finished |
Bob fixes knobs. |
Finally, I let Bob place the knobs.
Tuning the VCO proved problematic. Even after I let the board heat up for 20 minutes, I really had a hard time approaching the 1V/oct slope.
I'm not 100% sure yet, but the VCO is not very stable and slowly drifts, even with the tempco option installed. Is the circuit defective ? Is the design problematic ? Was it damaged during my early tests with a home made power supply ? I don't know. The rest works like a charm.
Tuning the beast |
Finally, all the Eurorack power flat cables I got for my DIY modules were 16-pin to 16-pin. And JP1 is aligned in a way it is not possible to use a 16-pin connector properly.
I had to divert the 10-pin to 16-pin cable from Rings to put the module in place.
Time to buy some 16-pin to 10-pin cables next time I guess.
Finally in place. Ready to wiggle.
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