Simple LC Oscillator

[pidja105]

Hello,
I want to build simple LC oscillator but I know where is the input, I don't know where is the OUTPUT for attaching two wires for obtaining frequency.Can you tell me where I can attach that two wires? Thanks!

 

[LvW]

Input? An oscillator does not have any input (just DC supply).
More than that, there are many different LC oscillator topologies.
Show us your circuit.

 

[pidja105]

http://www.electronicshub.org/lc-oscillator-basics/ on that page LC tank circuit.

 

[pidja105]

Input? An oscillator does not have any input (just DC supply).
More than that, there are many different LC oscillator topologies.
Show us your circuit.

http://www.electronicshub.org/lc-oscillator-basics/ on that page LC tank circuit.

 

[LvW]

An LC tank circuit is not an oscillator because of unavoidable resistive losses within the circuit. You neeed an amplifier.

 

[BobK]

Here is a practical circuit for a Colpitts's oscillator.

The C in the LC is computed as C1 and C2 in series, in this case 50n.

The output comes from the collector of Q1.

 

[AnalogKid]

As shown on the 9th image on the page you linked, the output comes from the output of the opamp.

ak

 

[Colin Mitchell]

As soon as you attach the two wires and try to read the frequency, you will load the circuit and it will stop working and you will get NO OUTPUT.

 

[AnalogKid]

Not true, of course. The opamp output is a low impedance voltage source designed to provide a signal output to some other circuit or use. Connecting between the opamp output pin and the circuit ground is the best way to observe the oscillator output signal. Another way is to connect a high impedance scope probe across the L-C tank, but this will change the oscillator circuit frequency. If the impedance of the equipment being connected is too low, such as 50 ohms, it can cause the oscillator to stop. However, oscilloscopes or frequency counters usually have a high impedance option.

ak