This circuit can activate a powerful lamp or call system when a telephone call occurs. Suitable for hearing impaired or noisy places it was found in American documentation in the 90s.
Depending on the transformer used, the power of this inverter can reach 300 W. This is a critical...
This circuit from an old American publication uses a 12 V transformer and an incandescent lamp in an...
This circuit with an unusual configuration was found in the January 1974 issue of Radio...