Today we will look at the latest module for a VIP signal (quack) - this is a power amplifier. Recently they brought me a quack with a failed UMZCH. If you own such a device, then you don’t need to turn it on for more than 10 seconds - the amplifier will burn out! Well, if you have a quack like the cops, then you can safely turn it on as much as you want! In police quacks, the signal is amplified using a sound converter with powerful transistors, which can work for hours without burning out. Chinese cheap signals use an amplifier based on TDA2003 microcircuits; thanks to the bridge connection of two microcircuits, it was possible to obtain a power of up to 30 watts. The power is, of course, insignificant compared to police 300-watt flashlights, but the sound is quite loud. You can also find it on our website. So, after turning it on, it became clear that the world circuits had burned out; they are very easy to get or buy on the radio market for a negligible amount. Microcircuits can also be replaced with TDA2002, although the latter are rarely found; the domestic analogue of the TDA2003 microcircuit is the famous 174un14.
The microcircuits were replaced, and the reason why they burned out was also found out - if you turn on the device for a few seconds, the microcircuits will boil, the fact is that they are placed on a common heat sink with a small area.
The heatsink was also replaced with a larger one. A typical bridge circuit for connecting amplifiers on the TDA2003 chip is shown below.
2 ohm resistors can be replaced with homemade ones. To do this, take the paste from a helium pen and wind 20 turns of wire with a diameter of 0.5 millimeters on it, turn to turn. You can wind it in two rows to make the resistor compact. All polar capacitors used in the circuit are selected with a voltage of 16 or 25 volts.
Power to the amplifier is supplied through a relay, but it can be excluded from the circuit, since here you can use a direct connection with wires, not so high currents so that the wires can't stand it.
The capacitance of the input capacitor can be deflected in one direction or another; this will not affect the operation of the amplifier and sound parameters in any way, since the amplifier works as a signal repeater. The load of the head, which is connected to an 8 ohm amplifier. It is known that the microcircuit can operate at a load of 2 ohms, with a bridge connection of 4 ohms; to increase the volume, you can use a small transformer (iron) with two windings. The primary must be connected to the amplifier output. The primary winding should have a resistance of 3.2-4 ohms, wound with a wire of 0.7-1 mm. We wind the secondary winding with the same wire and it should have the same resistance as the first. This way you can increase the power by 1.5-2 times. Author - Arthur Kasyan (AKA).
Before starting the article, I want to warn you that the use of such signaling devices is illegal, at best you will face a hefty fine. VIP signals have always been considered a luxury item and there are many car enthusiasts who would like to have such a device in their car. This is a device that generates powerful sound signals low frequency.
The signal consists of three main parts.
1) Control panel - in new models, very often the entire generator circuit is located in the control panel. Models such as the right have only one MK, which is programmed and has several operating modes.
2) Power amplifier - Amplifies the signal and supplies it to the emitter
3) Emitter - a loudspeaker that is designed to reproduce a signal.
The generator produces sawtooth pulses and feeds them to the pre-amplifier, then the signal from the pre-amplifier goes to the main power amplifier, in our case this amplifier is made using a cheap TDA2003 monophonic microcircuit.
The circuit has a matching transformer; the signal from the UMZCH goes to the primary winding of this transformer. The secondary windings of the transformer are connected to the bases of powerful key transistors. The signal forces the transistors to open, the latter supply voltage to the primary winding of a more powerful (power) transformer.
At the output of this transformer we already get amplified square wave, which is fed to the loudspeaker.
The generator (imitation of a quack) is built on a two-channel pulse generator and counter-dividers. To simulate the sound of a siren, the circuit has a separate microcircuit.
The design diagram is available in the full archive, the download link for which you can find at the end of the article (download is free).
Greetings, dear car enthusiasts and radio enthusiasts! It was sometime in February. A friend of mine, whom I have known for most of my life, asked me to build a Quack. The main conditions were: low price, powered by 12 Volts, the presence of at least one siren and, in fact, the “crack” function itself.
After a little searching for the circuit diagrams of these “quacks”, it turned out that it would be possible to assemble a useful device only on a microcontroller. I settled on a circuit with a PIC16F628A microcontroller. Until this moment, I was not familiar with microcontrollers, and so I had to read a little about them.
After reading a little about them, I realized that I would have to assemble a programmer and I chose the simplest JDM programmer, which consisted of only a few parts, namely a board, four resistors, a 5-volt stabilizer, a COM port connector, a 6F22 battery, and the actual microcontroller.
The programmer is extremely simple and therefore it took me literally 10 minutes to make it (not counting making the board).
Programmer circuit:
Ready programmer:
I hid all the “stuffing” of the programmer under electrical tape. This programmer can program PIC microcontrollers in DIP8, DIP14, DIP18 packages.
I programmed the microcontroller using the WinPic800 program. If suddenly someone’s programmer does not work the first time (like me), then check whether your COM port is enabled in the BIOS settings.
Quack diagram:
Photo finished device:
The diagram contains almost no details. In addition to the MK, 2 33pF capacitors and 4 MHz quartz are important in it, and the rest is essentially not so important. Sound effects are switched on by shorting the corresponding contacts to ground.
The “naked” scheme produces too much weak signal, and so it was decided to make an amplifier. We considered options such as TDA2003, TDA2005, TDA7294, TDA7265 and even a transistor amplifier, in the end it was decided to build an amplifier using TDA7265.
The amplifier is connected by a “bridge” and, according to the developers of the microcircuit, produces as much as 50 watts of power. The amplifier circuit was taken from the datasheet, changed quite a bit, and replaced the 1 µF electrolytes with film. And here is the diagram itself:
The amplifier turned out to be quite good, especially since I wasn’t chasing Hi-Fi, since it’s not needed here. According to measurements, the peak output power was about 40 watts.
I had a board lying around from some speakers for a PC and it just fit this chip, so I broke out the required piece and put the chip and all its few accessories there. The microcircuit does not require a small radiator.
Photo of the finished amplifier:
After assembling the amplifier, I thought about how to power the whole thing from 12 volts? The quack is okay, it requires only 5 volts, but the amplifier needs bipolar power supply +/- 20 volts. It was decided to make a converter using the well-known TL494 chip. It was done according to this scheme:
But I changed the circuit a little, namely, I lowered the power supply capacitors from 4 to one 2200uF 25V and instead of 4 field effect transistors, put 2.
It is advisable to use a 2-watt R13, as it gets a little hot. The converter is turned on by supplying “+” power to the “REM” contact.
The transformer is W-shaped without a gap, the primary winding is 5+5 turns, the secondary winding is 7+7 turns and 4 turns for powering the MK. Instead of IRF3205, IRFZ44 and the like are quite suitable.
Photo of the finished converter:
The converter turned out to be quite good and its power is quite enough to power the amplifier. Everything was placed in a metal case and covered with cardboard. The control panel was placed in a plastic case.
Photos of the finished “Quack”:
The microcircuits were replaced, and the reason why they burned out was also found out - if you turn on the device for a few seconds, the microcircuits will boil, the fact is that they are placed on a common heat sink with a small area.
The heatsink was also replaced with a larger one. A typical bridge circuit for connecting amplifiers on the TDA2003 chip is shown below.
2 ohm resistors can be replaced with homemade ones. To do this, take the paste from a helium pen and wind 20 turns of wire with a diameter of 0.5 millimeters on it, turn to turn. You can wind it in two rows to make the resistor compact. All polar capacitors used in the circuit are selected with a voltage of 16 or 25 volts.
The power for the amplifier is supplied through a relay, but it can be excluded from the circuit, since here you can use a direct connection with wires, the currents are not so large that the wires cannot withstand.
The capacitance of the input capacitor can be deflected in one direction or another; this will not affect the operation of the amplifier and sound parameters in any way, since the amplifier works as a signal repeater. The load of the head, which is connected to an 8 ohm amplifier. It is known that the microcircuit can operate at a load of 2 ohms, with a bridge connection of 4 ohms; to increase the volume, you can use a small transformer (iron) with two windings. The primary must be connected to the amplifier output. The primary winding should have a resistance of 3.2-4 ohms, wound with a wire of 0.7-1 mm. We wind the secondary winding with the same wire and it should have the same resistance as the first. This way you can increase the power by 1.5-2 times. Author - Arthur Kasyan (AKA).
When you press the "Start" button, the "Wail" siren starts; when you press the "Start" button again, the siren changes to "Yelp", in the mode of which you can press "End", which is also launched once when there is no siren. All sirens are interrupted by a quack - the "AirHorn" signal. The Stop button stops all sounds instantly. 
My development board looks like this. 
The siren is generated by the PIC16F628A microcontroller with 220 µs pulses. The project in proeus looks like this. 
I didn't make the printed circuit board, I'll leave it up to your discretion. The amplifier for this siren can be successfully used from my
There is also a version on PIC12F629. There is a "Wail" blueprint on board. It is turned on and off with one “Siren” button, which is also interrupted by a crack when you press the “Crack” key. The connection diagram is similar, only 2 control buttons are added. In Proteus it looks like this. 
The result was an option at 629/675 peak, all three sirens without using quartz. In Proteus it looks like this. 
Please note: do not overwrite the calibration constant when programming
The result was a version based on PIC16F84A, the pins were reassigned. Don't forget to pull the reset pin to the power supply.
Quartz at 4 MHz 
