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 TTL circuit was found in a 1978 technical documentation. The power must be supplied with 5 V....
This circuit, suitable for tube equipment, was found in an old documentation. It uses a high...
The BA1404 integrated circuit (not very easy to obtain) consists of a complete stereo FM...