HB Simulation in ADS

is it important to use a source in HB simulations, what if i don't know the output frequency of the circuit and i want to see the output spectrum, is there another way to see any output frequency?

regards

If input frequency is defined, the output frequency must be subset of input. I mean, the circuit will change the frequency in a linear correlation with input variable(s).

Eventough the circuit is nonlinear, output components will be combination of input signals or themselves...

HB simulator should know all frequency components tha will appear either input or output. Otherwise it won't work..