• Skip to main content
  • Skip to primary sidebar

Homemade Circuit Projects

Get free circuit help 24/7

New Projects | Privacy Policy | About us | Contact | Disclaimer | Copyright | Videos 

You are here: Home / Audio and Amplifier Projects / Make this Wireless Speaker Circuit

Make this Wireless Speaker Circuit

Last Updated on May 1, 2021 by Swagatam 36 Comments

The article explains a very simple circuit of a wireless speaker system which can be used for playing hi quality music wirelessly from your TV set, DVD player, Ipod, cell phone or from any music system. The speaker thus can be placed in any corner of the house within a radial distance of 50 meters and high quality music can be enjoyed without the hassles of long connecting wires.

For implementing the entire wireless speaker system, we actually need to make two sets of circuits, a transmitter circuit for transmitting the music signal from the source input as discussed above and a receiver circuit for receiving the transmitted music signal and for playing it in the attached speaker.

Transmitter Circuit:

As shown in the figure, the configuration looks a little different from the usual single transistor transmitter circuits where a single stage is used for the audio amplification and for the generation of the modulated carrier waves.

Wireless Loud Speaker Circuit Diagram
caution electricity can be dangerous

The usual single transistor transmitter circuit has the advantage of smaller and compact size and minimal power consumption, but is not suitable for long and strong signal transmissions.

However since such circuits are commonly used for wireless microphone applications, the distance is not a factor but compactness and low power consumption is definitely a must, and therefore becomes quite suitable for the intended application.

The present design is not intended for the above application so the first two features are not important, however the proposed idea of a wireless speaker system surely requires a long range and a distortion free power transmission, so that the reception can be heard at any corner of a particular premise or even across an apartment.

Therefore a stronger signaling or transmission of stronger carries RF signals becomes a necessity.

That’s exactly why we have incorporated a couple of extra stages in addition to the central carrier wave generator stage.

The first transistor and its associated components form a neat little audio amplifier stage and also a buffer between the audio source and the transmitter circuit.

This stage amplifies the received signal to stronger levels, and this stage also allows keeping the volume of the source signal to minimum levels.

The amplified signal is passed on to the next stage, which is the actual RF signal generator stage.

This stage is basically a simple feedback type of oscillator, wired to produce RF signals in the range of around 90 to 100 Mhz.

The amplified signal from the collector T1 start forces T2 to modulate the generated RF with the injected audio signals.

The modulated signal from the collector of T2 can also be directly used for the intended wireless music receiving.

However since we are interested in making it more powerful, we introduce another stage which becomes responsible for amplifying the modulated signals to much stronger levels so that it may be heard across many 10s of meters away and even in cell phone radios.

How to Make L1

The inductor L1 is the most critical part of the circuit. Its dimensions are: 1mm, super enameled copper wire, having 5 turns of 6mm diameter. The tap to C6 is taken by scratching the second last turn of the coil toward the positive side end.

The whole transmitter circuit can be built over a small piece of veroboard and housed inside a suitable sized metal box along with the required power supply section enclosed.

This concludes the transmitter circuit.

The Receiver Circuit

Ideally you won’t need to build this as the receptions can be heard crystal clear over an ordinary FM radio set. Therefore you might just want to use the FM radio itself as the wireless loudspeaker, or probably add an ampli-speaker box in conjunction to you FM receiver.

That’s it, your wireless speaker box system is ready and may be used for listening to any audio transmission without connecting wires across a radial distance of more than 50 meters, if the antenna is made large enough, the range may be well increased to beyond 90 meters.

Parts List

  • R1 =1M,
  • R2 = 2K2,
  • R3 = 470 Ohms,
  • R4 = 39K,
  • R5 = 470 Ohms,
  • C1 = 0.1 uF,
  • C2 = 4.7 uF,
  • C3, C6 = 0.001uF,
  • C4 = 3.3pF,
  • C5 = 10pF,
  • C7 = 100uF/16V
  • D1----D4 = 1N4007
  • L1 = See Text
  • T1, T2 = BC547B,
  • T3 = BC557B
  • TR1 = transformer, 0-9V, 100mA

Another Wireless Music Transmitter Circuit

The following diagram shows another miniaturized FM transmitter circuit that can be hooked up with a music source to send the music into the air in the wireless mode. A distant FM radio could be used as the wireless speaker is able to receive the signals and play the music.

The inductor L1 can be built by winding a piece of super enameled copper wire having a length of 6.5 inch, and thickness of 20 SWG over an air cored former having a diameter of around 1/4 of an inch.

Meaning, take a 6.5 inch long, 20 SWG super enameled copper wire and wind it over a 1/4 inch diameter air core former.

The music is fed from the input indicated as PL1

You'll also like:

  • 1.  Tracking Transmitter Circuit
  • 2.  1.5 watt Transmitter Circuit
  • 3.  USB 5V Audio Amplifier for PC Speakers
  • 4.  How to Make an Outstanding Home Theater System
  • 5.  SMPS 2 x 50V 350W Circuit for Audio Power Amplifiers
  • 6.  Long Range Transmitter Circuit – 2 to 5 Km Range

About Swagatam

I am an electronic engineer (dipIETE ), hobbyist, inventor, schematic/PCB designer, manufacturer. I am also the founder of the website: https://www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials.
If you have any circuit related query, you may interact through comments, I'll be most happy to help!

Have Questions? Please Comment below to Solve your Queries! Comments must be Related to the above Topic!!

Subscribe
Notify of
36 Comments
Newest
Oldest
Inline Feedbacks
View all comments

Primary Sidebar

Categories

  • 3-Phase Power (15)
  • 324 IC Circuits (19)
  • 4017 IC Circuits (52)
  • 4060 IC Circuits (26)
  • 555 IC Circuits (99)
  • 741 IC Circuits (20)
  • Arduino Engineering Projects (83)
  • Audio and Amplifier Projects (115)
  • Battery Chargers (83)
  • Car and Motorcycle (94)
  • Datasheets (73)
  • Decorative Lighting (Diwali, Christmas) (33)
  • Electronic Components (101)
  • Electronic Devices and Circuit Theory (36)
  • Electronics Tutorial (120)
  • Fish Aquarium (5)
  • Free Energy (34)
  • Fun Projects (13)
  • GSM Projects (9)
  • Health Related (20)
  • Heater Controllers (29)
  • Home Electrical Circuits (103)
  • How to Articles (20)
  • Incubator Related (6)
  • Industrial Electronics (28)
  • Infrared (IR) (40)
  • Inverter Circuits (98)
  • Laser Projects (12)
  • LED and Light Effect (93)
  • LM317/LM338 (21)
  • LM3915 IC (25)
  • Meters and Testers (66)
  • Mini Projects (149)
  • Motor Controller (67)
  • MPPT (7)
  • Oscillator Circuits (26)
  • PIR (Passive Infrared) (8)
  • Power Electronics (34)
  • Power Supply Circuits (79)
  • Radio Circuits (10)
  • Remote Control (48)
  • Security and Alarm (61)
  • Sensors and Detectors (121)
  • SG3525 IC (5)
  • Simple Circuits (75)
  • SMPS (29)
  • Solar Controllers (61)
  • Timer and Delay Relay (53)
  • TL494 IC (5)
  • Transformerless Power Supply (8)
  • Transmitter Circuits (41)
  • Ultrasonic Projects (16)
  • Water Level Controller (45)

Calculators

  • AWG to Millimeter Converter
  • Battery Back up Time Calculator
  • Capacitance Reactance Calculator
  • IC 555 Astable Calculator
  • IC 555 Monostable Calculator
  • Inductance Calculator
  • LC Resonance Calculator
  • LM317, LM338, LM396 Calculator
  • Ohm’s Law Calculator
  • Phase Angle Phase Shift Calculator
  • Power Factor (PF) Calculator
  • Reactance Calculator
  • Small Signal Transistor(BJT) and Diode Quick Datasheet
  • Transistor Astable Calculator
  • Transistor base Resistor Calculator
  • Voltage Divider Calculator
  • Wire Current Calculator
  • Zener Diode Calculator

© 2023 · Swagatam Innovations

wpDiscuz