Abstract: A ripple current component detecting circuitry embodied in the terminal of a cable connecting a battery charger with a lead acid storage battery to improve safety of use by preventing the indication of a correct polarity of connection where a charger is energized before connection is made with the battery when in fact such an indication may be incorrect, the prevention of such an indication being accomplished by the utilization of the AC ripple component in the charger output. The circuitry detects the ripple and with its use overrides what would otherwise be given as a misleading indication of polarity.

Abstract: This invention relates to a battery charger which includes a timer which becomes energized upon a battery approaching a fully charged condition and the timer then commences a preset timed equalization or finishing charge which brings each cell of the battery into a 100% fully charged condition. The battery may remain connected to the charger which includes a restart monitor which causes the charger to automatically re-charge the battery to a fully charged condition when it senses that the battery is losing its charge.

Abstract: A circuit for detecting ringing signals on a telephone line in which the alternating voltage oscillations are converted to direct current pulses which are used to charge a first capacitor. Only signals of 14 hertz or above are sufficient to repetitively charge the first capacitor to a high enough voltage to open continuously a grounding circuit through a comparator, thus, allowing a second capacitor to charge up and open a second grounding circuit thus permitting current to flow to a suitable output. The output is used to activate lights on the telephone which lights are either flashed or winked by a unique resistance balanced solid state flash or wink generator.

Abstract: An adapter circuit for converting dialing generated tone bursts on a telephone line into DC pulses of a length equal to the tone burst length so that the percent break may be measured. The DC pulse is initiated when the tone burst reaches 50% of its full value and terminated when the tone burst decays to 50% of its full value.

Abstract: A circuit for detecting ringing signals on a telephone line in which the alternating voltage oscillations are converted to direct current pulses which are used to charge a first capacitor. Only signals of 14 hertz or above are sufficient to repetitively charge the first capacitor to a high enough voltage to open continuously a grounding circuit through a comparator, thus, allowing a second capacitor to charge up and open a second grounding circuit thus permitting current to flow to a suitable output. The output is used to activate lights on the telephone which lights are either flashed or winked by a unique resistance balanced solid state flash or wink generator.