ICSS FAILURE CAUSES TOTAL LOSS OF COM IN TWR.

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ALL CTL POS; ALL MAIN AND STANDBY FREQS FAILED. ACFT WERE IN VARIOUS PHASES OF FLT ON BOTH TWR FREQS; AND WERE ALSO TAXIING ON GND FREQ. 2 MINS PASSED BEFORE POS WERE RESET AND 2-WAY COMS WERE RE-ESTABLISHED. SUPPLEMENTAL INFORMATION FROM ACN 290118: WHILE I WAS BRIEFING ANOTHER CTLR (MY RELIEF) FOR LC1 (1 OF OUR TWR POS) WE EXPERIENCED TOTAL FAILURE OF THE ICSS POS; RESULTING IN LOSS OF ALL RADIO AND LANDLINE COM CAPABILITIES ON THIS POS. A TWIN CESSNA ON AN OPPOSITE DIRECTION PRACTICE INST APCH HAD PREVIOUSLY BEEN INSTRUCTED TO EXECUTE A MISSED APCH ON A 2 MI FINAL IF HE LOST COM WITH US. WHEN HE COULD NOT REACH US; HE COMPLIED WITH THESE INSTRUCTIONS AND BROKE OFF HIS APCH. A UCR IS PENDING REGARDING THIS SIT. I HAVE ALSO EXPRESSED A COMPLAINT TO THE FAA ADMINISTRATOR'S SAFETY HOTLINE. I'D APPRECIATE ANY OTHER SUGGESTIONS YOU MIGHT HAVE TO HELP GET THIS PROB CORRECTED. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: RPTR STATED IT WAS THE ICSS THAT FAILED CAUSING LOSS OF COM. ONLY 1 GONSET SET IN TWR. ICSS IS OLD AND WAS INVESTIGATED BY FAA AIRWAYS FACILITIES TECHNICIANS. TECHNICIANS SAID HUMIDITY WAS CAUSING STATIC ELECTRICITY AND KNOCKING OUT THE SYS. SYS NEEDS TO BE GNDED BUT THEY ARE TRYING A HUMIDIFIER IN THE TWR TO SEE IF THAT SOLVES THE PROB.