... 'switched off' to avoid undue battery drain. With normal use, the battery should be charged every 3 days. When not used regularly, ... distance is found to be significantly shorter, replace battery immediately. The 3.6v rechargable battery operates the C button, this is the 'anti ... alarm sound from the ring on 3.6v battery sounds, the battery is exhausted and should be recharged.3) Owners, do not work on ...