ZHU CTLR RELEASED PROBLEMATIC MAIN/STANDBY RADIOS AFTER SUCCESSFUL BUEC TESTING BUT THEN LOST ALL RADIO CONTACT WHEN BUEC FAILED.

Narrative

ACFT X WAS ON CLBOUT FROM ZZZ APCH. THE CTR FREQ WAS HAVING PROBS AND THE SUPVR CALLED FOR ME TO CHK THE BUEC SO THAT THE MAINS AND STANDBYS COULD BE RELEASED TO MAINT. I DID SO ON VHF AND UHF AND THE BUEC WORKED. THE SUPVR RELEASED THE MAINS AND STANDBY TO MAINT AND I REMAINED ON THE BUEC. ACFT X CHKED ON AND I CLBED HIM TO FL230. A MOMENT LATER HE SAID THAT HE HAD AN INST MALFUNCTION AND NEEDED TO RETURN TO ZZZ IMMEDIATELY. I COORD WITH THE ZZZ APCH CTLR WHO TOLD ME TO ASSIGN ACFT X HDG 270 DEGS AND 13000 FT. I CLRED ACFT X AS DIRECTED AND INITIATED A HDOF. THEY TOOK THE HDOF AND I ATTEMPTED TO SWITCH ACFT X TO APCH. THERE WAS NO RESPONSE. I SOON REALIZED THAT NONE OF MY FREQS WERE WORKING. I HAD NO BACK-UP AND ALL OF MY ACFT WERE NORDO. I HAD TO DO A CONSIDERABLE AMOUNT OF PANIC COORD TO WARN ALL THOSE SECTORS AROUND ME OF THE LAST ASSIGNMENTS OF ALL THE ACFT I WAS WORKING. ACFT X FLEW THROUGH AN ARR CORRIDOR AND A DEP CORRIDOR. I WAS ABLE TO COORD WITH ALL 4 CTLRS INVOLVED AND THEY DID A GREAT JOB OF MOVING THEIR ACFT AWAY FROM ACFT X. I TRIED IN VAIN TO GET THE SUPVR'S ATTN. FINALLY ANOTHER CTLR WENT OVER AND TOLD HIM THAT I HAD AN EMER AND HAD LOST MY FREQS. THE EMER ACFT LANDED SAFELY AFTER RETURNING TO THE DEP FREQ ON HIS OWN.