This is a simple microphone preamplifier circuit which you can use between your dynamic microphone and any equipment designed to work with an electret microhone (2 wire connection to electret capsule). This amplifier amplifies the low level signal to the levels used by electret microphone input and uses the power from the device.
Circuit which works as an preamplifier which allows you to replace an electret microphone with a dynamic microphone.
Circuit protection: No special protection circuits used
Circuit complexity: Very simple one transistor circuit