Hafe-duplex two-wire DC power-line communication system
Hall effect alarm pull station
Hand held communication aid for the dumb
Hand safety flasher
Hand-held apparatus for monitoring drug-nutrient-mineral...
Hand-held electronic apparatus using two batteries sequentially
Hand-worn warning device and method
Handbag alarm system
Handheld devices as visual indicators
Handle for a ski-stick
Hard copy tone address paging system
Hazard detection, warning, and response system
Health care signaling device
Heating plant monitor system
Helmet warning device
High current inductive coupler and current transformer for...
High frequency network communications over various lines
High frequency network multiplexed communications over...
High frequency network multiplexed communications over...
High output smoke and heat detector alarm system utilizing a pie