undamped vibrating circle

[Peet19]

I want to build an undamped vibrating circuit. I would like some help with this.
The picture shows how far I've come, but it's not good that way.
Thanks for the help!

 

[Nigel Goodwin]

To be undamped you need no load on it - you have (roughly) a 1K load, the resistor in series with the low impedance of the pulse source.

You need some kind of switch feeding the tuned circuit, that goes O/C when turned OFF.

 

[danadak]

Here is a 1/2 uS current pulse into an ideal LC tank circuit.

Regards, Dana.

 

[Peet19]

I understand that it has to be fed back from the output, but how? How do they make radio transmitters?
Thanks to you too Dana.

 

[Nigel Goodwin]

I understand that it has to be fed back from the output, but how? How do they make radio transmitters?

That would be an oscillator, there are a wide variety of different types.

 

[Papabravo]

Your research should include:

1. Colpitts Oscillator
2. Pierce Oscillator
3. Hartley Oscillator
4. Armstrong Oscillator
5. Crystal Oscillator
6. RC Phase Shift Oscillator
7. Cross-Coupled Oscillator
8. Dynatron Oscillator
9. Meissner Oscillator
10. Optoelectronic Oscillator
11. Phase Shift Oscillator
12. Wine Bridge Oscillator
13. Robinson Oscillator
14. Tri-Tet Oscillator
15. Quadrature Oscillator
16. Bubba Oscillator
17. Van der Pol Oscillator

That should occupy your waking hours for a while

 

[Peet19]

Papabravo: OK, thanks

Nigel: What oscillator is in the picture? How is the feedback implemented so that the output frequency has a constant amplitude?

 

[Nigel Goodwin]

Papabravo: OK, thanks

Nigel: What oscillator is in the picture? How is the feedback implemented so that the output frequency has a constant amplitude?

I'm not sure what type of oscillator that is, but it's the usual crappy 'bug' type transmitter - there's also no feedback to specifically cause a constant amplitude.

The actual feedback is from collector to emitter, with the transistor operating in common base.

 

[Peet19]

Yes, I noticed that too. I didn't understand that there was feedback here.
I'm trying the Hartley oscillator.

 

[Tony Stewart]

You should learn the equations of impedance, resonance, Q and gain and run at lower frequencies 1st

https://tinyurl.com/24rzxk7z

 

[Peet19]

I understand, thanks.