A simple radio microphone. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Audio equipment
Comments on the article
I want to offer another circuit for a radio transmitter (radio microphone).
Based on a circuit published in amateur radio literature using a chip that I excluded. The scheme is good because it does not require varicaps, quartz and is assembled from available parts.
The range is 15...100 m, depending on the transmitting and receiving antennas.
Schematic diagram of the device is shown in the figure.
The L1 coil for the FM band has 4 turns, for the VHF band - 6 turns, on a mandrel Ø 0,3 mm, with a wire Ø 0,6 mm.
Any dynamic or condenser microphone can be used as a microphone. The use of the MKE-3 microphone is undesirable due to the high noise level.
Setting up the transmitter consists in setting the operating frequency by shifting and expanding the turns of the L1 coil. It is best to control the operation of the radio microphone on a VHF broadcast receiver.
Author: A.Melnikov, Mstislavl
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