Can Wood Be Used as a Capacitive Sensor in an LM358 Op-Amp Circuit?

AI Thread Summary
The discussion centers on using wood as a capacitive sensor in an LM358 op-amp circuit, questioning its effectiveness compared to skin. The circuit design is criticized for being flawed, leading to ambiguous output readings. It is noted that static electricity can influence the readings at pin 2, affecting the comparison with pin 3. Participants suggest providing a circuit diagram for clarity and emphasize the importance of understanding the intended application of the op-amp. Overall, the conversation highlights the complexities of using non-traditional materials like wood in electronic sensing applications.
hackhard
Messages
183
Reaction score
15
i connected pin 4 and 8 to gnd and +5 v respectively
.when pin 2 touches wood, or hand pin 1 is high.
i understand skin is capacitive , but wood?
 
Engineering news on Phys.org
Your circuit is badly designed so the output has no meaning. What about pin 3?

The output (pin 1) will be high if 1In- (pin 2) is lower than 1In+ (pin 3).

Static electricity on your skin or the wood can easily make pin 2 higher or lower than pin 3.
 
hackhard said:
i connected pin 4 and 8 to gnd and +5 v respectively
.when pin 2 touches wood, or hand pin 1 is high.
i understand skin is capacitive , but wood?

quite an odd post
How about posting about what you are actually trying to achieve with this op-amp :smile:Dave
 
  • Like
Likes sophiecentaur
A circuit diagram helps everyone to understand what's being discussed. You can't expect every contributor to make a personal sketch.
 
Thread 'Weird near-field phenomenon I get in my EM simulation'

Thread 'Weird near-field phenomenon I get in my EM simulation'

I recently made a basic simulation of wire antennas and I am not sure if the near field in my simulation is modeled correctly. One of the things that worry me is the fact that sometimes I see in my simulation "movements" in the near field that seems to be faster than the speed of wave propagation I defined (the speed of light in the simulation). Specifically I see "nodes" of low amplitude in the E field that are quickly "emitted" from the antenna and then slow down as they approach the far...
View full post »

Thread 'EMF (Electromagnetic Field) & EHS (Electromagnetic Hyper Sensitivity)'

Hello dear reader, a brief introduction: Some 4 years ago someone started developing health related issues, apparently due to exposure to RF & ELF related frequencies and/or fields (Magnetic). This is currently becoming known as EHS. (Electromagnetic hypersensitivity is a claimed sensitivity to electromagnetic fields, to which adverse symptoms are attributed.) She experiences a deep burning sensation throughout her entire body, leaving her in pain and exhausted after a pulse has occurred...
View full post »

Similar threads

Help for interpreting Opamps on a schematic
Replies
14
Views
3K
Building RF Noise Generator Circuit w/ LM324D SMD Op Amp
Replies
12
Views
4K
Design of an Op Amp Circuit for Voltage Amplification
Replies
9
Views
4K
Charlieplexing: LEDs have different brightness
Replies
14
Views
2K
Reference Pin on Differential Amplifier
Replies
3
Views
2K
Asking for Op Amp recommendations
Replies
7
Views
1K
Op-amp Circuit with virtual Ground
Replies
15
Views
5K
Question about Parasitic capacitances and physical grounds
Replies
5
Views
4K
Engineering Why is the voltage source high potential into node 1 at -12 V in this op amp problem?
Replies
15
Views
2K
How does circuit complete when using live wire tester?
Replies
7
Views
2K

Hot Threads

Recent Insights

Back
Top