UM66

www.DataSheet4U.com Musical Calling Bell By Kalyan Prodhan www.kalyan-prodhan.tk Connection Diagram Component List with cost (Approximate) Component Description (IC and Transistor) Precaution Modification for adaptation This is the simplest ever musical calling bell that can be easily built. It uses the musical 3 pin IC UM66 and a popularly known Transistor BC548b. The circuit can be made even without soldering and the ideal for the first electronic project for newbies. Here the musical IC UM66 generates the music when it receives supply and drives a small speaker through a class c amplifier using silicon transistor BC548b. Description: UM 66 Fig-1 : Connection Diagram The connection diagram is shown below. The component details with cost is also with this. The battery supply should be kept in a battery container to ensure the connection. The volume of the sound of this circuit is so much that it can be used as a calling bell. If anyone want to reduce the volume of the circuit then insert a resistance () in place of the blue line connection. In this circuit please don't give the supply beyond 3 volt without modification as the IC may got damaged. It is better that you should not run this circuit in Eliminator as most of the available eliminator don't have a good filter built in and have no precision over voltage protection. The circuit should not be run in Rechargeable battery also if the Speaker resistance is less than 8 Ohm and may burn the Transistor. www.DataSheet4U...