Why does my LC circuit not oscillate its energy between Electric & Magnetic fields?

Click For Summary
SUMMARY

The forum discussion centers on the failure of an LC circuit, comprising an 8-turn inductor and a 1 microfarad polyester capacitor, to oscillate energy between electric and magnetic fields. Despite initial current readings of 1 A, the circuit does not sustain oscillations, leading to a lack of detectable current or magnetic field after the initial discharge. Participants suggest using an oscilloscope for better measurement, increasing the number of turns on the inductor to lower the resonant frequency, and employing transistors for switching to maintain oscillations.

PREREQUISITES
  • Understanding of LC and RLC circuits
  • Knowledge of resonant frequency calculations
  • Familiarity with oscilloscopes and their usage
  • Basic electronics involving inductors and capacitors
NEXT STEPS
  • Research "LC circuit resonant frequency calculations"
  • Learn how to use an "oscilloscope for transient measurements"
  • Explore "transistor switching techniques for oscillation maintenance"
  • Investigate "high-Q RLC circuits and their applications"
USEFUL FOR

Electronics enthusiasts, hobbyists experimenting with oscillating circuits, and students studying circuit theory will benefit from this discussion.

  • #151
Baluncore said:
Can you hear the oscillator as a silent frequency on the AM radio ?
Yes, at last! It's between 600 and 800, somewhere in between, see for yourself where the slider is:
IMG_20241004_134438.jpg
 
Reply
  • Like
Likes   Reactions: Baluncore
Physics news on Phys.org
  • #152
LTspice simulation of your circuit shows that the 1 uF emitter capacitor, C3, seems to pull the frequency up, closer to 1 MHz than the expected 700 kHz.

If you move the AM radio further from the oscillator, you should get a more accurate frequency reading on the smaller signal.
 
  • #153
Baluncore said:
LTspice simulation of your circuit shows that the 1 uF emitter capacitor, C3, seems to pull the frequency up, closer to 1 MHz than the expected 700 kHz.

If you move the AM radio further from the oscillator, you should get a more accurate frequency reading on the smaller signal.
If I place the AM radio 1 centimeter away from the inductor or from the antenna, the 700 KHz frequency goes completely silent. Otherwise, the noise reduces in intensity but not completely. The antenna does not have the right length to emit at a large distance. Half a meter away the noise reappears. It also silences 1400 KHz.
 
Last edited:

Similar threads

High School A question about induced current in LC circuits
  • · Replies 4 ·
Replies
4
Views
1K
High School Why do capacitors not discharge everything immediately in LC circuits?
  • · Replies 15 ·
Replies
15
Views
2K
High School LC resonance with high Q factor, Inductor with non magnetic core
  • · Replies 4 ·
Replies
4
Views
2K
Graduate Charging and Discharging of a capacitor in an LC circuit
  • · Replies 50 ·
2
Replies
50
Views
14K
Undergrad Do Oscillations Occur in Inductors When Modifying AM Transmitter Circuits?
  • · Replies 30 ·
2
Replies
30
Views
3K
Determining Inductance L in an LC Circuit
  • · Replies 5 ·
Replies
5
Views
2K
Undergrad Lc Circuit Question: Understanding Oscillations and Polarity Changes
  • · Replies 8 ·
Replies
8
Views
3K
What explains the current flow in a LC circuit?
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Why in a LC circuit does the current reverse ?
  • · Replies 7 ·
Replies
7
Views
5K
High School Ion Trap and Time-Varying Potentials
  • · Replies 1 ·
Replies
1
Views
2K