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.
In the figure we have an application for NLAS5113, a new device from on Semiconductor...
We found this phonographic transmitter for the MW band in a 1956 documentation. The circuit has a...
The circuit shown below was obtained from an Italian magazine Sperimentare from 1977. All...