linger Improvement, best practices, lessons learned

[Andres Ramos]

Here we are summarizing everything that proves as useful in terms of

• Best setup for the LINGER (Settings)
• Which audio feed to use to modulate the LINGER
• Optimized environmental conditions
• technical improvements in the LINGER design

[Andres Ramos]

Adding a microphone

First  outcome of Jonathan's tests and Karyns comments is that it would be useful to implement a microphone in the device to provide means to record the experimenter questions alongside with the spirit signal.

Technically this should be done with an

• electret condenser microphone capsule built into the frontpanel
• the usual transistor preamplifier
• a second OpAmp to mix the noise signal from the phototransistor with the microphone
• Microphone level adjustment is needed->another potentiometer

[Andres Ramos]

5V power supply redesign

• Rework design down to 5VDC power supply
• Use USB charged power bank for supply with standard USB charging connector in the housing
• Consider using the MCP602 douple OpAmp to replace the TL071/2