Caffeine Information. Caffeine is naturally found in cocoa beans, coffee beans and tea and is synthetically produced for use in certain medications and in beverages. This substance is a stimulant drug that quickly enters the bloodstream and affects the brain.
Frequency Range Chart. The radio spectrum refers to the section of the electromagnetic spectrum that holds all possible radio frequencies ranging from 3 kHz to 300 GHz.Radio frequency is used for radio communication technology, wireless networks and telecommunication systems.he radio spectrum refers to the section of the electromagnetic spectrum that holds all possible radio frequencies ranging from 3 kHz to 300 GHz. Radio frequency is used for radio communication technology, wireless networks and telecommunication systems.
1 A frequency band in which the. 2  of the upper frequency limit to the lower frequency limit is 2 to 1. 3  When making acoustic measurements, ten bands may be utilized, with the following approximate center frequencies: 31.5, 63, 125, 250, 500, 1000, of the upper frequency limit to the lower frequency limit is 2 to 1. 2  When making acoustic measurements, ten bands may be utilized, with the following approximate center frequencies: 31.5, 63, 125, 250, 500, 1000, , 3  4000, 8000, and 16000 Hz.