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 80's Motorola circuit can generate 100 MHz signals, but they can reach 200 MHz with the...
Of course, the current is extremely small, but a voltage of 300 V can be obtained from 9 V of a...
We found this solid-state relay circuit that can function as a shield in a Radio Electronics...