Better! I want it BETTER!
After a lot of good suggestions from users, I have put together some possible
upgrades for this project. They enhance noise, safety, and
- The LF353 isn't the best choice for an op-amp. Although it worked,
it has potential for more noise than other op-amps. With that knowledge, I
would suggest the LM324. It has 4 op-amps, so you only need two.
It's also cheaper ($0.33). Plus, you can buy it at Radio Shack. (For about
5x more money)
- ISOLATION! For people interested in isolation, you probably need to
put in an analog-to-digital converter prior to isolating. This will make
it easier since cheap optocouplers are only good for digital signals. If I
find a good, cheap way to isolate the circuit, I'll post it.
- Capacitors across VDD to GND may be good. It may depend on how
strong your battery is, and what brand. Another capacitor from VDD/2
to GND will also be helpful with noise.
- A potentiometer instead of the 200k resistor will give you a settable
- Shampoo and KY Jelly make a better electrode gel.
- Hopping up and down on one foot makes your heart beat faster.