I designed the Colpitts oscillator.
However, when the output is connected to the oscilloscope, only the value of 5V is output.
In this situation, connect the output to be measured to terminal A and connect the function generator to terminal B. Also, when you look at the oscilloscope, it looks correct at the 5V output of the Colpitts circuit.
Why is this happening?
The Colpitts oscillator in the example has a good value when A is connected.