Sine wave frequency multiplier

[Noel Paul A]

I need to multiply with a factor of 2.7 for a sine wave having frequency of 2 to 4 kHz

[HarryA]

The only way I can think of to do that is to  use two circuits. First a frequency to voltage converter circuit. Then feed the voltage output of that circuit into a voltage to frequency converter circuit.   One can find such circuits by searching on the internet.  A circuit simulator would be helpful here.

The 9400 chip can be used as a voltage-to-frequency or frequency-to-voltage converter. Perhaps there is a newer chip?

Hopefully someone else will have a better idea for you 😐

[Ylli]

That's a job for a digital phase locked loop.  Input and output can both be sine waves, but the processing is best done digitally.

[HarryA]

That is a good idea but how do you get the divide by 2.7 required ? Is the best one can do is to  divide by 5 then by 2  or 10 and 4 for 2.5 perhaps.

There is a good phase locked loop frequency multiplier tutorial at: www.youtube.com/watch?v=5by0os8RrFY

[Ylli]

Divide the input signal by 27 (after squaring it up) and divide the output signal by 10 (after squaring it up).  Feed both to the phase detector and the error voltage back to the output oscillator.