This circuit with 117 V output was found in a 1969 Electronic Design. Drive transistors admit equivalents and information about transformers is not given.
This low drift circuit for thermocouple was found in an old European documentation. However, it is...
This complete single cell protection system is suggested by Linear Technology in its 2005 manual....
This simple circuit of low power with an LM386 includes the highly sensitive audio preamplifier...