The doorbell housing 702 contains a camera module, an LED indicator, a processor and memory including programs executed by the processor. The doorbell camera 106 is electrically coupled to 1052 a remote chime 1006 via a bypass unit 1012 powered by a transformer 1010 that provides an input AC voltage. The remote chime 1006 is configured to ring 1054 in response to a user press on the doorbell button 1002. A supply monitoring signal is generated 1056 by the doorbell camera 106 based on the input AC voltage to indicate whether the input AC voltage is greater than a supply threshold. Based on a value of the supply monitoring signal, a user is notified by the doorbell camera 106 as to whether there is sufficient voltage to power the doorbell. In accordance with the supply monitoring signal, a message is presented by the doorbell camera 106 to a user of the doorbell camera 106 to indicate whether the input AC voltage is low with respect to the supply threshold.