This circuit is from an 80's publication. It makes use of small 6 V x 50 mA incandescent lamps. The diodes can be general purpose or even 1N4002. The transformer is 6.3 V with 100 mA or more current.
This circuit was obtained in a 1970 EEE and applies to almost any operational amplifier. The...
This configuration can be found elsewhere in this section. This was obtained from old RCA...
August 2017 - STMicroelectronics' BlueCoin development environment is available at Mouser...