I provide you with a special signal circuit (Cracker), for self-assembly. I decided to put the child on bike (even if he scares passers-by under the house), but it’s also possible in car put (if there is a connection in the traffic police). This device consists of a minimum of parts, as well as being easy to assemble and within the power of everyone.
To build this device, we need:
1) PIC16F628 - microcontroller
2) Speaker
3) 33pF Capacitors
4) Quartz crystal 4 MHz
5) Buttons
6) Textolite or thick cardboard
Scheme of the device itself
Outputs 18 and 17, as written in the diagram, go to the UM (Power Amplifier) if you do not have it, I will tell you how to do it below, but for now we connect a simple speaker to these outputs.
To simplify the assembly, I did everything by hinged installation, (so as not to fool with the grass of the boards) I took the adapter socket for the microcircuit, and also used all the details in the DIP package (whoever does it for the first time, I advise you to take it)
In a piece of PCB and cardboard (what anyone has), we make holes
We insert the adapter socket and solder all the components, according to the above diagram.
Everything is ready and requires the first trial run. But we still need to write the program to our microcontroller, it's simple, but who doesn’t know HERE There is a brief description of the process.
After the firmware, just insert the chip into the adapter panel and connect the power. Everything should work right away; no configuration is required.
Necessarily, we adhere to the established voltage of a food, for a microcircuit it should not exceed 5 volts.
Everything works, but only quietly, so that it would be louder we need a speaker for more. But the large speaker, this circuit also will not pull. Therefore, an AM (Power Amplifier) is required. The photo shows some of the simplest amplifier circuits.
I chose the easiest (top right)
Just two parts, a 5.1K resistor (I didn’t have it, set it to 6.8K) and the transistor took 2N3904, I chose a speaker for more. If the amplifier suddenly does not work, do not be alarmed, just take the speaker more powerful (I had it) and it will work.
My speaker was in a deplorable state, but that did not stop me from feeling the difference.
If you still want to put such a signal in your car, then you need a more powerful amplifier.
Below I posted a video of the signal without an amplifier and with it, as well as the firmware file of the microcontroller. If you don’t have a programmer, please contact the PM or in the comments, I will help with the firmware. And do not forget, setting this signal on a car is OUTSIDE THE LAW !!!!!
Firmware