Today it is no longer considered fashionable to solder various shiny details on a makeshift circuit board, as it was twenty years ago. However, amateur radio clubs still exist in our cities, specialized magazines are published in offline and online modes.
Why has interest in electronics plummeted? The fact is that in modern stores everything that is required is sold, and there is no need to study anything or look for ways to acquire it.
But not everything is as simple as we would like. On sale there are wonderful speakers with active amplifiers and subwoofers, wonderful imported stereo systems and multi-channel mixers with a wide range of capabilities, but there are absolutely no low-power
low-frequency amplifiers
. As a rule, they are used to connect tools at home, so as not to destroy the psyche of neighbors. It’s quite expensive to buy a device as part of a powerful device, the following will be a rational decision: to exert yourself a bit and create a home-made amplifier without any help. Fortunately, today it is possible, and Uncle-Internet will help with this with pleasure.
Amplifier, "assembled on the knee"
The attitude towards self-assembled devices today is somewhat negative, and the expression “assemble on the knee” is excessively negative. But we will not listen to envious people, but immediately turn to the first stage.
Initially, you must select a scheme. A home
- made
sound amplifier such as ULF can be made on transistors or a microcircuit. The first option is extremely not recommended for beginner hams, as
semiconductor devices clutter up the board, and the repair of the device will be complicated. It is best to replace a dozen transistors with one monolithic chip. Such a homemade amplifier will delight the eye, it will turn out compact, and to assemble, it will take a little time.
To date, the most popular and reliable chip is the TDA2005 type. It is already a two-channel ULF in itself, it is enough to organize power supply and provide input and output signals. Such a simple home-made amplifier will cost no more than a hundred rubles, along with other parts and wires.
The output power of the TDA2005 is in the range of 2 to 6 watts. This is enough to listen to music at home. The list of used parts, their parameters and, in fact, the circuit itself is shown below.
When the device is assembled, it is recommended to screw a small aluminum screen onto the microcircuit. Thus, when heated, the heat will dissipate better.
Such a homemade amplifier is powered by 12 volts. For its implementation, a small power supply or an electric adapter with the ability to switch the output voltage values is purchased. The device current is not more than 2 amperes.
You can connect speakers with power up to 100 watts to such an VLF amplifier. The signal from a mobile phone, DVD player or computer can be input to the amplifier. The output signal is removed through a standard headphone jack.
Thus, we figured out how to assemble an amplifier in a short time for little money. The rational decision of practical people!