Passive 1KHz frequency shifter. Can it be done?

[neazoi]

Hello,
I know about passive RF signal doublers or harmonic generators, but I was wondering if there is a way to passively shift a receiving signal at a frequency Fo, to Fo+1KHz or so.
Thank you

 

[betwixt]

Not as far as I know. A mixer is the only solution I can think of but with only 1KHz difference, filtering the unwanted mixer products might be a problem.

Brian.

 

[KlausST]

Hi,

you can double frequency by rectifying it.

But i can imagine that only a triangle signal gives a kind of undistorted output (with DC filter).
Any other frequency - or even worse a mixture of frequencies like speech - won´t give satisfying results.


Klaus

 

[FvM]

I was wondering if there is a way to passively shift a receiving signal at a frequency Fo, to Fo+1KHz or so

Theoretically yes, using a quadrature mixer scheme. Practically it depends on your ability to generate exact 90 degree phase shift for the input signal and LO and the intended other side band suppression.

 

[neazoi]

I was wondering if this can be done Passively, i.e. no power applied to the circuit, not even other frequency RF power, other than the input signal frequency itself.

 

[BigBoss]

I was wondering if this can be done Passively, i.e. no power applied to the circuit, not even other frequency RF power, other than the input signal frequency itself.

Passive circuits are always LTI ( Linear Time Invariant ) circuits and they have no frequency shift properties.