This high impedance headphone amplifier was found in American documentation from the 1990s. Any general-purpose FET can be used.
Mouser Electronics already has in stock the new RF transceivers Atmel / Microchip ATA8820 SIGFOX ™ for...
This circuit can be used as a low Power audio booster for experimental projects such as radios,...
With a mains-rated transformer and 1:1 winding this benchtop circuit was found in the January 1995...