DENVER, Pa. – Long before the era of instant entertainment from TV, downloaded music and streaming videos, Americans could amuse themselves with a pocketful of change at an arcade. The thrilling atmosphere of those places, whether indoors or on a seaside boardwalk, resonated with the clanging and whirring of slot machines, the pinging of bagatelles, and orchestral tunes performed by mechanical music machines. Coin-ops were also found in saloons and other social establishments. Today, the mechanical entertainers of yesteryear are displayed in collections from coast to coast, often flanked by antique advertising signs of the same period. Many of the rarest and finest of all antique coin-ops and signs have passed through the doors of Morphy Auctions, which will hold its next sale of these popular specialties on May 4-6. Bid absentee or live online through LiveAuctioneers.