voltage spike is generally random in nature and the temperature cool down cycle of the varistor thermistor is dependent on ambient room conditions which may vary from hour to hour or day and night or heating season to cooling season the randomness of the unit is enhanced the 34 remote module 34 or pulse coupling circuit can be plugged into the outlet of a conventional light timer the timer cord plugged into the 34 remote module connector 34 and the combination can be set to operate within desired hours other applications would be to connect a suitable window switch normally open when the window is closed which would detect when a window is open and switch on a circuit containing the remote module and thereby turn on a lamp to produce pulses that would be detected within the house or at the neighbors via another unit with just a 34 remote module 34 as a receiver element the sensitivity is adjustable by the selection of the proper gate resistance and primary coupling circuit values with further reference to the circuit shown in fig7 the optional heating resistor shown as r h dotted may be used as a heat producing element in addition to.