DIY ECG notes

PARTS for higher-precision version(s)

• Instrumentation Amplifiers (not sure why these are priced so differently)
  • Both have CMMR of 110+ for gain of 1000, so they should both work equally well. AD624AD is referenced in the sciam article, but it also mentions the AD620A which is 1/3 the cost at about $7.
  • Cheaper version: AD620A
  • Expensive version: AD624AD

PARTS for basic version(s)

• LM358 or LM324 (quad vs dual) op amps (or LF353 which is pin compatible)
• Diodes
• 0.1uF capacitor(s)
• Variety of 1/4 watt resistors (10k, 100k, etc)
• shielded wires for electrodes (phone or coax cables)
• electrodes (soldered pennies, medical electrodes, etc)

References

These sites, papers, and articles provide info on ECG making, A/D conversion, and signal processing:

• OpenECG Project
• Scientific American, Shawn Carlson
• DIY ECG, Scott Harden
• DIY ECG Improvements, Scott Harden
• DIY ECG, Jason Nguyen
• ECG Measurement System, Chia-Hung Chen, Shi-Gun Pan, Peter Kinget
• DIY ECG howto (AD620A used in schematic) by Refik Hadzialic
• AVR ADC tutorial (a little old)