4G technologies are designed to provide IP-based voice, data and multimedia streaming at speeds of at least 100 Mbit per second and up to as fast as 1 GBit per second. 4G LTE is one of several competing 4G standards along with Ultra Mobile Broadband (UMB) and WiMax (IEEE 802.16).
An electrical ballast is a device placed in line with the load to limit the amount of current in an electrical circuit. It may be a fixed or variable resistor.
How to Replace the Ballast in a Fluorescent Lighting Fixture. All fluorescent light fixtures consist of at least lamp(s), lamp holders, ballast and internal wiring. Some older types have starters, too. The ballast is used to create the voltage and current necessary to start and illuminate the fluorescent lamp.