To enhance the applicability to circuit boards of different specifications without requiring any circuit board with a connector inserting hole and also prevent solders from slipping off from the soldered part.

The power supply adapter is furnished with a body and at least one guide terminal, and each guide terminal is continued to and contacted with the guide connector having a through hole and a winding region, and the bare wire end of an electric wire is passed through the through hole, wound round the winding region, and soldered fast thereon. The guide connector as another item of the invention to be continued to and contacted with an electric wire having a bare wire end and insulating sheath is equipped with a through hole and a winding region, wherein the bare wire end and part of the insulating sheath are passed through the through hole, and the bare wire end is wound round the winding region and soldered fast thereon.