The transistors of this circuit found in an English 1980s documentation may be the modern BC548 equivalents. The circuit is battery powered and the earphone must be crystal.
Toshiba MOSV MOSFETs These and others from the same line of Toshiba power MOSFETs are available from...
June 2017 - Mouser Electronics has a broad line of Cree products for use in horticulture, such as...
August 2017 - Mouser Electronics is stocking the new Molex optical EMI shielding adapters. These...