A film substrate in a mounting structure of electronic components has positioning holes capable of positioning the electronic components passing therethrough. The user equipment separately manages back-off operations for each of the CCs, and performs a random access preamble transmission using the relevant CC if another usable CC exists, even when a back-off period is being applied to a specific CC, to carry out a random access process in an efficient manner in a carrier aggregation mobile communication system. The delivery receptacle emits infrared beacons from one or more IR beacon transmitters. The first and the second resistive circuits are dimensioned so that the fault potential range lies outside of the one or the plurality of defined measuring potential range. Four current sourcing elements respectively communicate with first terminals of the first, second, third, and fourth bias transistors.