Found in a 1924 documentation, this circuit is powered by 3 batteries, two of which are high voltage. The output is a high impedance headphone jack.
The figure shows how to drive a load up to 300 mA with an LM3900. The transistor can be a BD136. We...
This circuit was obtained in a 1969 Mullard manual. The transistors are from that time. The input...
August 2017 - STMicroelectronics' BlueCoin development environment is available at Mouser...