questions connecting Pulse sensor to Ganglion
I am trying to stream pulse sensor PPG data using a ganglion board on OpenBCI. Here's how I have connected it:
1) Pulse sensor red wire (power) - Ganglion DVDD
2) Pulse sensor black wire (ground) - Ganglion GNDA
3) Pulse sensor purple wire (analog input) - Ganglion Pin 2+
The PPG input is connected to pin 2+. Pin 2 - ve is connected to D_G. However, PPG signal shows up on channel 1, 3 and 4. The output text file also has the PPG data written on channel 1,3 and 4. Channel 2 shows some random values. Any clue what might be the issue with this? I have attached a screenshot of the openbci gui for your reference. In image 1, pins (1,3,and 4) are left floating. In image 2, negative pins (1,3 and 4) are also connected to D_G. Gives a cleaner signal. Thanks!