21 CODE-SIGNAL ENCODERS, CODE-SIGNAL DECODERS, [ MOBILE RADIO CALL INDICATORS, ] RADIO CONTROLLED POCKET PAGERS, CODE-SIGNAL MEMORY BANKS, [ ENCODER-DECODER COMBINATION UNITS, ] ADJACENT CHANNEL REJECTOR ATTACHMENTS, POWER SUPPLIES, HOOK-UP CABLES [ , RADIO RECEIVERS, AND MOBILE TELEPHONE CONTROL HEADS ]