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.
In the figure we have an increased dynamic response configuration with the use of a transistor (TR3) in...
This tuned circuit was found in a 1966 Electronic Circuit Handbook. The transistor can be any...
This transmitter for the 40 meter or 7 MHz band was found in a magazine 73 for radio amateurs of...