Hello dear radio amateurs! Now I am assembling 4.1 acoustics on the TDA7650 and TDA1562, automotive microcircuits, for the home, of course, it could have been better to choose, but this is not about them, but about a preamplifier with a tone block. I've always wanted to customize the sound for myself. And so I decided to assemble such a tone block. The choice fell on the TDA1524A chip. And now we will talk about assembling this miracle from scratch, using LUT technology for the manufacture of a printed circuit board. The standard scheme, according to which we will assemble the tone block on the TDA1524A, is shown in the figure:

To begin with, we cut off the desired piece of textolite, skin it with zero, degrease it with acetone.

He carefully wrapped it, and began to ruthlessly fry the paint so that it would transfer from paper to textolite.

After ironing, give the board time to cool. Next, the case is transferred to the bathroom. We put the board in water in order to let the paper soften. At this time, you can drink tea or coffee - who prefers what.

It's a beautiful photo, isn't it? Let's go further, after we have refreshed ourselves, we can move on to the most, in my opinion, painstaking task - rubbing paper from the textolite. Carefully tear off the paper so as not to tear it off along with our tracks.

All that remains, without fanaticism, rubbed with fingertips.

Then we move on to the important thing - etching. I usually pickle in ferric chloride, as it is faster than pickling in blue vitriol (at first I poisoned them, but was disappointed, because the wait was up to 2 days). Gently place the board in the solution so as not to splatter.

Now you can go for a walk, or do something else. An hour has passed, you can get our payment. Usually it is etched faster, but I found textolite in the store only 2-sided, and the solution is not the first freshness. We take out the board and see our tracks.

The tracks are now under the toner, it needs to be cleaned off. Many people do this with acetone, or another solvent. I do it with the same fine skin.

That's all, the stage of preparing the board for the tone block circuit has been completed. Further it will be more interesting - we drill holes for parts.

There is nothing more to drill than with a drill, it is extremely inconvenient, especially since her cartridge is staggering. So don't scold too much for crooked holes :)

We produce soldering parts of the tone block. We start doing this with a socket (connector) for the TDA1524A chip.

Now we solder all the jumpers and small parts. We insert the microcircuit last, since during soldering it can overheat and fail, which is very sad.

Well, that's basically it! Below is a photo of my tone block.

After soldering, we check the absence of a short circuit, snot between the tracks, if nothing like this is noticed, then you can safely turn it on. Video demonstration of the device:

I always carry out the first start with a serial connection of a 12-volt car light bulb (for current limiting in the event of a short circuit). Tembroblok assembled - everything works fine. The article was written by: Eugene (ZhekaN96).

Specifications of the regulator: Frequency band 20-20 000Hz Tone control at 40Hz (bass) -19/+17db Tone control at 16Khz (treble) -15/+15db Balance control -40db Input impedance 10-60K Output impedance 300Om Volume control not less than -80 /+21.5db Harmonic coefficient no more than 0.3% Relative noise level no more than -80db Supply voltage 6-18VThis circuit is implemented on a Philips TDA1524A integrated circuit (A1524A is an analogue of the RFT company). The microcircuit is a two-channel (stereo) volume control, balance and timbre of low and high frequencies. There is also loudnes (frequency compensation). Variable resistors can be used any, because. volume, balance and timbre in this microcircuit is carried out electronically. Trimmer resistors R7 and R8 regulate the gain of the output signal, the button S1, which turns on the frequency compensation of the volume control (off in the diagram), must be latched. For those who want to constantly use frequency compensation without the possibility of turning it off, elements S1 and R9 can be excluded from the circuit. During operation, the microcircuit heats up. Glue to it (for example, with Moment glue) a small U-shaped aluminum radiator. This will increase the reliability and service life of the microcircuit.

On the printed circuit board shown here with dimensions of 50X31 mm, in addition to the volume control, balance and tone, there is a power amplifier described in the article Power amplifier on the TDA1552Q. The devices are separated on the board by a red dotted line. On the left is the volume, balance and tone control on the TDA1524A, on the right is the power amplifier on the TDA1552Q. The elements of the amplifier R1 C3 are soldered from the side of the printed conductors.

List of radio elements

Designation	Type of	Denomination	Quantity	Note	Score	My notepad
U1	Dual channel volume, balance and tone controls	TDA1524A	1			To notepad
C1, C2	Capacitor	68 nF	2			To notepad
C3, C4	Capacitor	15 nF	2	film capacitor required		To notepad
C5		100uF	1			To notepad
C6-C9	Capacitor	0.1uF	4	film capacitor required		To notepad
C10	electrolytic capacitor	100uF	1			To notepad
C11, C12	Capacitor	0.22uF	2	film capacitor required		To notepad
C13, C14	electrolytic capacitor	2.2uF	2			To notepad
C15	Capacitor	0.022uF	1	film capacitor required		To notepad
R1-R4	Variable resistor	47 kOhm	4			To notepad
R5, R6	Resistor	10 kOhm	2

Volume, balance and tone control on TDA1524A.

If you collect any sound-reproducing equipment, you will certainly need a device that will adjust the volume, balance and timbre of the sound. All these adjustments can be implemented by the TDA 1524A chip with a small number of additional elements. Below is a typical circuit for switching on this microcircuit; there is no need to invent something else. As you can see, there are only four potentiometers in the circuit: the first adjusts the volume, the second adjusts the balance, the third - high frequencies, the fourth - low frequencies. Those. adjustment is performed by one resistor at once for both channels (left and right). The power supply of the microcircuit is unipolar 12 volts.

The microcircuit has a loudnes mode (frequency compensation). Many are wondering what kind of mode this is, so let's write it as verbatim it is written in the answers to this question on many amateur radio forums:
The Loudness mode is loudness; a fixed or adjustable rise in low and (rarely) high frequencies at low volume levels to compensate for the drop in human hearing sensitivity at these frequencies. In our case, this frequency compensation is fixed.
The microcircuit is operational with a large spread of the supply voltage of 6 ... 18 volts.
Many radio amateurs who have repeated this scheme write that the microcircuit heats up during operation, so glue a small radiator or a strip of aluminum bent into a U-shaped shape in advance, it will be more reliable.

The board for the regulator is made of one-sided foil fiberglass. The view from the side of the tracks is shown in the figure below:

The following image shows the finished controller.

Please note that the picture shows a board with installed variable resistors, these potentiometers are 100 kOhm each, they are paired. Therefore, on the printed circuit board, both halves of the resistor are connected in parallel. The result is 50 kOhm. But you can also use single 47 kΩ resistors as shown in the diagram. The reason for using paired resistors is that when using them, mechanical strength increases, the resistors sit more rigidly on the board, and when the regulators are screwed to the front panel of the amplifier, there is no need to additionally fasten the board to the chassis.

Of course, the board could be made a little more compact, so if you don’t like this option, you can make your own adjustments there, or make a board according to the drawing shown in the following image:

This printed circuit board is made according to the diagram below:

The wiring diagram for power supply, as well as input and output signals is as follows:

Circuits for audio equipment

TDA1524 volume, balance and tone control

Chip TDA1524- active volume, balance and tone control with variable resistor control. In addition, the microcircuit provides the LOUDNES function (frequency compensation).
Scheme quite simple and it is quite possible to assemble it yourself.

Scheme of switching on the TDA1524 microcircuit

Technical characteristics of the TDA1524 chip

Frequency band 20-20 000Hz
Tone control at 40Hz (bass) -19/+17db
Tone control at 16Khz (treble) -15/+15db
Balance adjustment -40db
Input impedance 10-60K
Output impedance 300Om
Volume control not less than -80/+21.5db
Harmonic coefficient no more than 0.3%
Relative noise level no more than -80db
Supply voltage 6-18V

Variable resistors can be used any, because. volume, balance and timbre adjustment in this microcircuit is carried out electronically (voltage is applied to the inputs).
Trimmer resistors R7 and R8 regulate the gain of the output signal, the button S1, which turns on the frequency compensation of the volume control (off in the diagram), must be latched. For those who want to constantly use frequency compensation without the possibility of turning it off, elements S1 and R9 can be excluded from the circuit.

Important point : The chip heats up during operation.
Therefore, it is advisable to glue a small U-shaped radiator made of aluminum to it.

I have long had a desire to assemble an amplifier, albeit simple, but with my own hands. Involves the process itself. But I'm a total novice at this, just learning. I learned a lot on the Internet, I found a lot of interesting things on this Radio Portal (respect to Igor).
I decided to assemble my first VCL on, because. quite easy and simple to repeat. This microcircuit is used in most 2.1 type computer acoustics amplifiers, it has a good sound and has established itself as a good budget one.

What I needed for the amplifier:

1. Resistors
Resistors R6 and R7 MLT-2, the rest MLT-0.125.
Coil L1 wound on a resistor R7 with a 0.7 mm wire, made 8 turns.

2. Capacitors
C1 - ceramic, in extreme cases - non-polar electrolytic; C2 - ceramic; C4, C5, C6 - film, it is better to increase the capacitance of shunt capacitors C5, C6 as far as possible up to 0.47uF. C3, C7, C8 - electrolytes with an operating voltage of at least 50V. Capacitance C7, C8 should be desirable from 2200uF and can be increased as much as possible.

3. Microcircuit
I used two TDA2030A chips. The microcircuit is equipped with the following integrated protections: - against a short circuit of the output to ground or power supply; - from overheating. This circuit is powered by a bipolar source: - ±15V.

What I needed for the power supply:

1. 12V transformer.
Got it from computer acoustics Jet Balance.

2. Diode bridge.
I put which one was at hand - D3SBA60 already at 600V.

3. Capacitors.
Filtering I put 6 pieces of 1000uF at 35V. The output is a conventional film from 0.33 to 0.47 microfarads.

4. Stabilizers
I installed integral IL7812 and IL7912.

There were discussions on the old portal about the L1 coil at the output. Someone said that she was absolutely inappropriate, someone on the contrary claimed that she was just right. Tried with it, tried without it. There is no single answer. There is a plus - a surprisingly complete lack of background. I ended up leaving the coil. Then I began to play with the denominations of the capacities C2 and C3. Conder C2 picked up by ear from 100pF to 220pF (according to the scheme). I considered it optimal to put 150pF, as they say "golden mean". As for the capacitance of C3, everything is much more interesting here: if you set 22mF according to the datasheet, you get quite distinct and clean highs with a middle, and a weak bass. If you set the capacitance more, as Skif advises, increase it to 47mF, then the picture changes in the other direction. Bass is nice and clear, highs and mids are understated. On the advice of Igor (Datagor), I put a sandwich of several capacitors, instead of one. Capacitances of 22uF, 10uF and 4.7uF were at hand. I tried to blind 22uF and 10uF. The sound picture has improved, but not as much as I would like. Then I decided to put 2 at 10uF and 2 at 4.7uF with a total capacity of about 30uF. "Sandwich" has done its job. The sound is surprisingly balanced! Many thanks to Igor for the advice!

Having collected 2 channels (stereo) I decided to listen to my creation. For wiretapping, I chose two acoustic options: Radiotehnika S-30B (modified) and Radiotehnika X-Line FS-10.1. The sound started up from the computer (Creative SB Live 5.1 modified), foobar2000 player.

You know, at that moment I was visited by such an inexplicable feeling - a feeling of joy. My creation "sang"! After listening to a bunch of different tracks for 2 hours, I was satisfied, despite the fact that this VCL is considered "childish". The main thing, as they say, was to start somewhere.

I didn’t find a signet for the timbre block on this mikruha, or rather I just searched badly and therefore stuck it on as best I could. And my main mistake was that out of ignorance I put "red flags".

The sound upset me instantly. I was fiddling, I thought what the problem was, until I accidentally stumbled upon an article on the Internet in which I categorically did not recommend using these capacitors. Replaced them with film and beauty! Various unhealthy overtones and interference disappeared.

I didn’t have to make the case myself, because. somewhere far away on the mezzanine I found an old satellite decoder lying around, which was already morally outdated and it was just a pity to throw it away. I quickly gutted and placed my mustache in it, although it took a little sweat to get everything settled down properly.

This is what my First Amplifier looks like. Of course, it took a long time to assemble and bring to a normal state, about half a year, despite the fact that it takes another day to assemble it at the most. You understand - sometimes a wild lack of time, then holidays, and the most pleasant thing is the birth of a daughter.