This preamplifier for phonographic capsules using FET was found in 90s American documentation. Consumption is very low. The power can be obtained from the amplifier circuit with which it works.
This circuit provides a signal of higher frequency the greater the intensity of the light incident on...
This circuit was obtained from a 1978 Practical Wireless. It generates a low frequency, low...
This circuit can be used as a lockable shield. A pulse activates the relay that remains on even...