11 meter band In the 1950s.
 

A curious history. Most information is found on forums. The band that
would become Citizens Band began its current life in 1952 ish as an
Amateur Radio band that was shared with mostly unregulated medical
equipment that had primary access to the band. Diathermy (?) machines
were the biggest source of interference but there were others...

https://plus.google.com/+ToddCarpent...ts/Q18pjfTmskF

--
Eduardo
Sorocaba-Brasil
www.alt119.net - Art-Culture