|The RCU subracks, with one of the RCU boards pulled out. (Photo: D. McKay-Bukowski)|
On these RCU boards are mostly switches and filters, but this then goes in to the sampler. This is a 12-bit analogue to digital converter, sampling at 160 or 200 megasamples per second (depending on the configuration). Once the signal has been digitised, down-converted and filtered the processing chain is common.