"A"
"B"
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"
'Ha' to 'Hd', 'He', 'Hf' to 'Hor', 'Hor' to 'Hz',
HALF-Duplex. Data flow in either direction, but not in both directions at the same time. There are a number of interface buses that only allow Half-Duplex operation, while some bus networks just add a redundant path in the opposite direction to allow communication in either direction at the same time. Operation in both directions at the same time is called Full-Duplex. An Abbreviation for half duplex is HDX.
HALF-POWER POINT. A point on a waveform or radar beam that corresponds to half the power of the
maximum power point.
HALF-WAVE RECTIFIER. A rectifier using only one-half of each cycle to change ac to pulsating dc. Half-Wave Rectifier Circuit
HALF-WAVE VOLTAGE DOUBLER. Two half-wave voltage rectifiers connected to double the input
voltage.
Hard Disk Drive
Hard Disk. [HD] A flat, circular, rigid plate with a magnetizable surface on one or both sides used to store data. Also called a Hard Disk Drive [HDD]. Note: A hard disk is distinguished from a diskette [floppy Disk] by virtue of the fact that it is rigid. Manufacturers of Hard Disk Drives
HARD-TUBE MODULATOR. A high-vacuum electron tube modulator that uses a driver for pulse forming. See Vacuum Tube.
HARMONIC. A frequency that is a whole-number multiple of a smaller base frequency.
HARNESS. An assembly of wires or cables, or wires and cables arranged so it may be installed or removed as a unit in the same electronic or electrical equipment.
HDLC. High-level Data Link Control is a group of protocols for transmitting [synchronous] data Packets between Point-to-Point nodes. Data is organized into a frame in HDLC. HDLC protocol resides with Layer 2 of the OSI model, the data link layer.
Next set of "H" Terms and definitions
