HC-1 Table-type magnet telephone 
 Introduction ?HC-1-type magnet Telephone (work by hand magnet generator) for the wired telephone communications. 
 First, the basic properties: 1, light is re-matching lines. 2, two phones with the type of pass. Communication distance of up to 21 km. 3, can be minus 40 degrees Celsius - 50 degrees above zero Celsius, relative humidity of 98% reliable work environment. 
 Weight: about 1.75kg 
 Use something like this: 1, connected to the city, then, so that not only answer the phone call 
 2, two phones with the model magnet series, of course, many phones can be in series, you can call each other 
 Principle: A cell phone use, this battery is guaranteed to run the circuit, and a phone call when phone B to B to ring. A call to B in time, a hand shake to handle phone which has a small generator, power generator is turned, resulting in increased internal voltage telephone lines, and then did not pick up the party began to ring, pick B machine after the voltage drop, the call begins.