Input Device: Hello Mic
I made the hello.mic.45 board. There were a few little tricks I used
that are documentation-worthy.
The Board
Trick 1: Separate microphone input pads from the edge of the board
by hand with a knife. This allowed me to use the board without cutting
it along the bottom edge.
Trick 2: Mount a two-pin jack for the microphone input. Be sure that
the pin contacts do not contact the outside of the board. Use a grinder
to align the edge of the board with the jack - this allows plug access.
Trick 3: The condenser microphone fits directly into the plug of a
two-pin connector. This allowed me to avoid any messy soldering of the
pins, and easy microphone replacement in the event of malfunction.
The Interface
When listening to the board, power the ground and DTR pins with a
9V battery. This decreases the noise visible in the hello.mic.45.py
terminal by a factor of about 3. Thanks for the tip, Jonathan.