Wireless Microphones, Part 2
In Part 1 of the Wireless Microphones piece, I described wireless mic limitations, preferred locations of mic and receiver, RF link budgets and antenna polarization. In Part 2, we'll cover radio frequency names, antenna patterns and compression/expansion circuits.
Superlatives
Us techno-geeks are quick to toss out acronyms like VHF and UHF without a care, hoping that no one will bother to ask why a user might choose VHF or UHF as the frequency band for transmission. Starting with HF (high frequency), we move up to VHF (very high frequency), then on to UHF (ultra high frequency), then to SHF (super high frequency) and, believe it or not, EHF (extremely high frequency). Each of these high-frequency superlatives stand for a range of frequencies, or bandwidth. HF has 3 megahertz to 30 megahertz, VHF has 30 megahertz to 300 megahertz, UHF has 300 megahertz to 3 gigahertz, SHF has 3 gigahertz to 30 gigahertz, and EHF has 30 gigahertz to 300 gigahertz. And these are all waves per second of radiated electromagnetic energy, better known as radio frequencies (RF).
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