An experiment is proposed that uses a pair of RF cavities as a source and detector of hidden sector photons (HSP). HSP's are hypothetical low-mass dark matter candidates with coupling to ordinary photons. SRF cavities are favoured in this experiment as they are able to store a high number of photons for a given input power due to the high Q available. When powered, such a cavity will act as a source of HSPs, while an empty cavity will be able to capture any HSP's decaying back into RF photons. Such an experiment (CASCADE) is being developed at the Cockcroft Institute using single cell 1.3 GHz cavities previously utilised for manufacturing and BCP studies. The aims of the CASCADE project are detailed, along with the system specification.