High quality radio mikes have been available for about thirty years now. Some early systems tended to be cumbersome and unreliable but, by the mid-sixties, solid state miniaturization produced reliable units with reasonably high audio quality. At that time, the choice in radios usually came down to two units: the (American) Cetec Vega or the (English) Micron. Most who used them would tell you that the Micron was superior but they were less effectively marketed in this country. There were very few places where qualified service was available and units often had to be shipped to England for repairs or even tune-ups. The Vegas were less elegantly designed but they were rugged and service was available locally. Eventually they came to dominate the American market.

In those days only VHF units were available and most mixers chose "traveling" frequencies in the 169-174 MHz range. The VHF channels are allocated to a number of applications including standard television broadcast and are very crowded. For this reason, radio mikes were only permitted to broadcast over a very narrow frequency range, or bandwidth. These VHF radios typically had a bandwidth of only 12 kHz or 15 kHz. Output power of the VHF transmitters was also restricted by the FCC to only 50 mW. By way of comparison, a cellular handheld phone typically operates around 1 Watt or 20 times the output of a radio mike transmitter.

In the last ten years we've witnessed considerable progress in radio mike development and also some set-backs. Interestingly, we now find ourselves in an analogous situation with an American and an English design competing for the market.

In spite of many design improvements, the performance of radio mikes has become more problematic than it had been in earlier years. The VHF band is more crowded with TV stations, portable phones, garage door openers, and an endless variety of radio equipment and small appliances with motors which throw off RF energy. Manufacturers have recently moved to UHF frequencies to get some "clear air." The UHF designs have some definite advantages:

The UHF bands are much less crowded (for the moment) and units operate with less likelihood of interference.

FCC regulations limit VHF transmitters to 50 mW but permit up to 250 mW output in UHF.