This sound relay or Vox was found in 70s RCA documentation. SCRs can be common types today and transistor a BC558. The circuit is for the 110V power grid.
This analog thermometer was obtained from an English documentation. The sensor is a common diode...
This circuit is a kind of Hertz Loop that can be used to check the operation of transmitters and...
Two 3-terminal regulators like the LM317 can be used to "clip" a sinusoidal signal, in order to...