A system for color printing in an economical, simple, yet accurate manner comprises a computer which causes an inkjet printer to print a multi-color image of ink on the surface of a pad. The method includes modulating a relay-node-specific physical downlink control channel based on a relay-node-specific reference signal, and transmitting the R-PDCCH and the PDSCH to the relay node. Instead, it obtains electrical power from existing lighting points. A synthetic synapse is also provided. The communication between the inlet reservoir and main reservoir consists of plurality of ports distributed circumferentially each port being provided with a check valve. In addition, the improved scan tool determines a communications drop-out with one or more modules and automatically recovers from the communications drop-out.