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Symbol for megahertz, i.e. 106 hertz.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006




McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


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(MegaHertZ) One million cycles per second. MHz is used to measure the transmission speed of electronic devices, including channels, buses and the computer's internal clock. A one-megahertz clock (1 MHz) means some number of bits (1, 4, 8, 16, 32 or 64) can be manipulated at least one million times per second. A two-gigahertz clock (2 GHz) means at least two billion times. The "at least" is because multiple operations often occur in one clock cycle.

Both megahertz (MHz) and gigahertz (GHz) are used to measure CPU speed. For example, a 1.6 GHz computer processes data internally (calculates, compares, copies) twice as fast as an 800 MHz machine.

Why Isn't It Faster?
A CPU in the new computer billed as twice the MHz or GHz as the previous computer does not mean twice as much finished work gets done in the same time frame. Internal cache and CPU architecture plus the speed of the RAM, storage and network all contribute to the computer's actual performance and overall throughput. See cache.

Users are often dismayed to find only incremental improvements after purchasing a so-called "faster" computer. In addition, newer versions of software are sometimes slower than previous versions, and a faster computer is often required just to maintain the same performance level as the old software. See instructions per second, Hertz and space/time.

MHz and GHz Are the Heartbeat
When referencing CPU speed, MHz and GHz rate the raw, steady pulses that energize the circuits in a chip. The German physicist Heinrich Hertz identified electromagnetic waves in 1883, and coincidentally, "Herz" in German means "heart."

Speed and Width
Megahertz (MHz) and gigahertz (GHz) are the CPU's clock speed, and the number of bits (8, 16, etc.) are the width of the CPU's registers. The combination of speed and width determines the inherent processing performance of the CPU chip. Parallel channels from the CPU to external devices are also measured by speed and width; however, serial channels are rated only by speed. See parallel transmission, serial transmission and PC data buses.
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References in periodicals archive ?
Comment: It has secured a valuable 90 MHz in the 3.6 GHz band and 40 MHz of 2100 MHz spectrum
It went on to say that removing 121.5 MHz beacons from the marketplace won't impose significant costs on users based on the price differential between 406 MHz ELTs and 121.5 MHz systems.
The petition stated that while Liberty was no longer engaged in broadcasting business, "and despite the underutilization or, worse, non-utilization at all of the conditionally assigned said frequencies within the prescribed period, respondent Liberty continued to illegally hoard the said 700 MHz broadcast frequency."
For more information on T-Mobile's network and the impact of 600 MHz Extended Range LTE on coverage, visit www.t-
After the auction, the market leader Grameenphone totaled 37 MHz of which 7.4 MHz in 900 band, 15.6 MHz in 1800 band and 10 MHz in 2100 band to serve 65.32 million subscribers while Banglalink owns a totaled 30.6 MHz -- 5 MHz in 900 band, 15.6 MHz in 1800 MHz and 10 MHz in 2100 band to serve 32.38 million customers.
The average linear distance between the lens equator and ciliary process, the difference value (D-value) between the same cross section of the above bilateral linear distance in the normal subjects and the lens subluxation in the most significant direction, the diagnostic accuracy, and the testing times obtained with 25 and 50 MHz UBM were compared.
aeruginosa to high frequency-electromagnetic field (HF-EMF at 900 MHZ and 1800 MHZ), led to reduction in viable counts since the number of CFU/ml of exposed bacteria was observed to be significantly different (p<0.05) after exposure when compared to controls which were not exposed to radiation.
All telecommunications companies except for Vodafone obtained frequencies on the best frequency band of 900 MHz and part on the other frequency band.
While Airtel acquired 173.8 Mhz spectrum across 1800/ 2100/ 2300 MHz bands, Idea Cellular won 2100 Mhz band spectrum in Mumbai circle.
Globe's first 700 MHz site is located near Hardin ng Bougainvillea in UP Diliman, Quezon City, benefitting customers within a radius of 2.2 kilometers from the cell tower.
The chip used with these antennas is a custom-made chip [12, 13] which has a measured input impedance at 433 MHz for an output voltage of 1V which is around 425 - j 1200.