Microphone Circuits

Microphone Circuits
Microphones: #'s - D E - N MS T - Z

Last Updated: June 02, 2021 01:44 PM

Links to electronic circuits, electronic schematics and designs for engineers, hobbyists, students & inventors: -

Telephone Line Audio Interface - This device connects the telephone line to a home theater system or PA system (receiver only) . It is phone line powered and features automatic volume control (AVC) . It also mutest itself when a phone is picked up to prevent feedback. __ Designed by Andrew R. Morris

The Big-E Stereo Parabolic Microphone - This device is a stereo amplifier for a high sensitivity stereo parabolic microphone. It can be used for listening to distant sounds. Typical parabolic microphones are monophonic, this unit has a stereo audio path that helps produce more realistic sounding audio. The Big-E can be used with headphones or as an audio source for a stereo recorder. It can be plugged directly into a computer sound card's aux input. __ Designed by © G. Forrest Cook January 1, 2005

The PortaPAL Public Address System-Part 1 - It's packed with features, is easy to build and rivals commercial systems costing much more__ SiliconChip

Tube Microphone Preamp - This preamp design started out as a conventional three stage cascade with feedback RIAA equalization. I decided on 6SL7's running into 6SN7's. I figured it would be a good match (electrically and asthetically) for my 2A3 Amp. After thinking it through I thought I might just try passive RIAA. (Even a better matchno feedback!!!) I noticed a neat RIAA preamp circuit in the back of the RCA Tube Manual RC-19 that used a single 7025 per channel __ Designed by Bob Danielak

Using a Speaker as a Microphone - A circuit to Impedance Match a Speaker as a Mike. Speakers can make a Good Microphone for some applications. Bigger Speakers may also have a Good Low Frequency Response. Ever seen a 15 Inch Microphonethis Circuit will do it __ Designed by G.L. Chemelec

Using ECM Mic Inserts - This page describes how to use or connect and use 2 and 3 terminal electret condenser microphones (ECM's) . The bottom section shows the connections and how to substitute from one type to another. __ Designed by Andy Collison

Vacuum Tube Microphone Preamp/Direct Box Project - from January1997 EQ Column, includes phantom power supply

Variable Amplifier Impedance - Figure 1 shows two amplifiers (shown as opamps) , with (a) being conventional voltage drive, and (b) is current drive. The output impedances are in the order of zero ohms and infinite ohms in each case (this IS a theoretical discussion at the moment!) . The gain will appear to be exactly the same for each into an 8 ohm resistive load, __ Designed by Rod Elliott ESP

Voice-Over - This is a circuit where a microphone and preamp circuit (voice circuit) have priority over any other audio signal. You can think of this as a one way intercom, if the main amplifier is used for listening to music, then when the push to talk switch is pressed, the amplifier is switched to the voice signal. __ Designed by Andy Collison

Wireless Microphone - Circuit & notes only, no circuit description given. __ Designed by Tony van Roon VA3AVR

Wireless Microphone FM Transmitter - This Wireless Microphone FM Transmitter has been a very popular project with beginners and experienced constructors alike. It has been used inside guitars and as the basis of a remote control system. I do however, receive many requests for a higher powered circuit and better microphone sensitivity. Now I can introduce the new FM Wireless Microphone, which also has a better frequency stability, over 1Km range (under ideal conditions) and is good on microphone sensitivity. This has been achieved by adding an RF amplifier buffer (with 10dB gain) and an AF preamplifier to boost the modulation a little.

wireless microphone transmitter - Schematic only __ Designed by Peter Jakab

Wireless microphone using 741 opamp & 2N3904 - Schematic only

Wireless PA for Classrooms - In large classrooms, many a times the teacher’s voice is not audible to students in the back rows. So the teacher have to literally shout to be heard by every student....__ Electronics Projects for You

Microphones: #'s - D E - N MS T - Z