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Showing posts from March, 2023

Test Fixture and Calibration - Eurorack MIDI to 16x16 CV Gate Module

This design, along with its firmware and scripts were made so that the CVs of the  Eurorack MIDI to 16x16 CV Gate Module  (MIDI_16Gx16CV) could be calibrated and the other functions tested. That module is difficult to validate after assembly and had some teething issues that I wasn't able to figure out without a way to measure all of the CVs across a wide range of outputs. I tried to make measurements of the module manually on the first few I made but the results weren't amazing. The initial intent was for the main board of the MIDI_16Gx16CV to plug directly into the test fixture. The test fixture has connector sockets aligned with the main board. Unfortunately I made a classic mistake mirroring the design so I had to create some cables to connect the test fixture to the DUTs. In the end that worked out okay, I'm not sure it would have worked if the headers had been correct (for other reasons).  The test fixture uses an Arduino Pro Mini. To get enough I/O to read the gates

Eurorack Envelope Generator ADSR AS3310 v1 and v1.1

Here's an 8HP envelope generator based on the AS3310 chip. It's very similar to the  Polyphonic/Quad ADSR EG Module , because that was the starting point. I found myself needing additional ADSRs and that was the easy way to make one. To fit in 8 HP the circuit is split onto to PCBs. As with all of my designs, the signals in/out are 0-10V. The trigger input and switch is a new input on this (compared to the Quad ASDR). It appears to work; however, I haven't focused on testing it. Version one of the PCB had the out/release pins reversed on a header so the images below show rework for that. I had to rework and reorder another design so I quickly made a v1.1 for this at the same time and that corrects this issue. v1.0 PCBs in these photos require rework, but v1.1 is otherwise identical.          Module Width: 8 HP +12V Current: 26mA -12V Current: 26mA Design Files:  envelope_generator_AS3310 Schematic:  envelope_generator_AS3310_v1.1.pdf BOM:  envelope_generator_v1.1_bom This w