When this first appeared in the early 80s I think, because of the Film "Convoy" mainly. The whole Model World operated on 27 Mhz. Then along came the "Childish Babblers" and as an amusing hobby visit the Local flying or Boating Club and " Shoot down" a few very expensive models, never mind the danger of an uncontrolled aircraft crashing.HaHa, what a jolly jape!! So all said modellers had to pester for another frequency, which we got, 35 mhz.and 40 for boats and cars. Great, cost us a lot of money and frustration,as all our expensive Radio was obsolete and down right dangerous to use, but at last we were free of the Infantiles bleating " Breaker , Breaker, here is Mo the Moron reading you loud and clear" It all went a few years later, then we got Mobile phones!!