Back in the days of station exercises, long before mobile phones or even radiopagers, RAFP used to roar around the MQs in Cartoontown blasting away on a very loud two-tone air horn in order to invite participation in yet another pratteval of one form or another.
Often at 0-dark-00!
Eventually, the locals had enough - and the Stn Cdr was informed that, if ever this happened again, RAFP would be prosecuted under whatever law it is which forbids the use of car horns in built up areas between 2330 and 0700.
Although the horn was rather more effective than the tannoy which I once heard at about 0500 in the Brize OM in early 1984. After clearing his throat, the night porter (remember when we had such chaps?) politely announced, rather discreetly, "Good morning, exercise Taceval is now in force".....