EC seres High Frequency Transformer EC series High Frequency TransformerEC type transformer is the basic type of ferrite cores, ... circuit etc., with excellent material properties, for a typical transformer structure, EC core cylindrical center column, so that ... and choke coils. EC type transformer models EC2820, EC3542, EC4042, EC4950, EC5345, EC70, etc. Test conditions 1KHz/1V, pressure AC2000V, ...