Help me design a signal source to generate 50-310 MHz

i want to design a signal source to generate 50-310MHz.but no VCO coverage this range.any goog idea?

You can generate this by mixing 2 signal sources, for example a constant 1GHz source and a VCO that covers 1.05GHz - 1.31GHz. Use a good filter at the output.

If spectral purity is not a concern, there are ring VCOs that can cover this domain.

For VCO, look at MiniCircuits website.

you can generate a signal from 25-155MHz by DDS(eg. AD9954),and multiply the signal with 2, will get 50-310MHz