Suggested by Amperex in 1968, this circuit is intended for hearing aids. The integrated circuit used, a TAA370 is not common today.
The circuit shown in the figure is suggested by National Semiconductor and makes use of an...
We found this circuit in an old Mullard (Philips) documentation. The sensor consists of a...
This circuit is from 1987 documentation. The operating system used is not common today, but two...