Abstract: An antenna for a radio frequency transmitter or receiver carried in a wrist instrument is made as a loop of individually insulated multistrand wire embedded in an elastic fabric which comprises an expansion wristband for the wrist instrument, together with a capacitor embedded in a strap end. The multistrand wire is longer than the unstretched fabric and is either interwoven into the elastic field or sandwiched between two layers of fabric. The wire is folded back and forth in a serpentine shape in order to accomodate expansion. One end of the multistrand wire is soldered to a ground connection clip and the connection is embedded in a molded strap end. The other end of the multistrand wire is soldered to an insulated wire leading into the instrument case and to one lead of a capacitor. The other lead of the capacitor is soldered to a ground connection clip and all connections, as well as the capacitor are embedded in the other molded strap end.