In order to listen to records from a pocket player not through headphones, but through speakers, you need an amplifier. Modern integrated circuits make it possible to build very simple amplifiers using a minimum of external components.
Instructions
Step 1
Purchase the TDA7056A or TDA7056B chip. Place it on the heatsink of a large processor.
Step 2
Place the microcircuit together with the heatsink with the markings facing you, with the leads facing down. The first output will be on the left.
Step 3
Connect a loudspeaker rated at least 5 W between pins 6 and 8 of this microcircuit.
Step 4
Take a stabilized power supply with a voltage of 12 V, designed for a load current of at least 1 A. Do not turn it on yet. Connect the positive contact of the block to the output of the integrated circuit at number 2, and the negative contact to the pins 4 and 7 connected together.
Step 5
Take an electrolytic capacitor with a capacity of 220 μF, rated for a voltage of at least 16 V. Connect it, observing the polarity, in parallel with the power supply. In domestic capacitors, the positive pole is indicated by a plus, and in imported capacitors, the negative is indicated by a vertical strip of minuses.
Step 6
In parallel with the electrolytic capacitor, connect a ceramic with a capacity of about 100 nanofarads. The polarity of its inclusion is indifferent.
Step 7
The input signal is applied to pin 3 through a ceramic or paper capacitor with a capacity of 0.47 μF. If the signal source is stereo, take two capacitors and feed the signals to them, and connect the leads of these capacitors opposite to the signal source together. Connect the common wire of the signal source to the negative pole of the power source.
Step 8
Set the volume on the signal source to minimum. Turn on the power to the source and amplifier. Gradually increase the volume on the signal source until you hear a sound.
Step 9
If you want to make a stereo amplifier, get another IC of the same type, turn it on in the same way, and connect to another speaker. Apply the signals from the stereo channels to the microcircuit inputs through separate capacitors. Use a more powerful power supply designed for a load current of at least 2 A.
Step 10
Make a case for the amplifier in any way convenient for you. Place the loudspeakers in separate enclosures, if desired, or make them part of the amplifier. Make holes in front of the speaker cones for sound to escape. Also make holes on the rear walls of all enclosures: the amplifier needs them for cooling, the loudspeakers need them to improve the sound quality.
