Well, the pulsed transmission is not going to be heard on a UHF receiver as they are very short duration.

Try this on the debugin:

Code:
sigstrength:

    IF jump = 1 THEN rssioff     ; check input to reset to serial                                             
    DEBUGIN  3000,sigstrength,[WAIT("aSSRSSIS-",dec3 sigfield)]    ; get slave signal strength value                                        
    DEBUGIN  3000,sigstrength,[WAIT("aMMRSSIM-",dec3 sigcontrol)]  ; get control signal strength value 
    
    LCDOUT  $FE,$80," Light Unit ",sigfield                                       
    LCDOUT  $FE,$C0," Control Unit ",sigcontrol                                         
    GOTO sigstrength
Ioannis