What Snoboy said. I have heard that the life of a transceiver is much like that of a climbing rope. It becomes less trustworthy with age and should be replaced if suspect. I suppose the beacon could be sent to the manufacturer for verification of frequency etc. Frequency drift is a serious issue in the case of analog to digital transmission. Some of the new digitals wont pick up analog signals that are off frequency. So when doing your beacon check at the start of the ski, have the person with the digital do the check.