Give a signal to 4 relays randomly at regular intervals?

Question

Do it yourself

The scheme is the following. There are 4 relays. These relays should be given a 12V signal at random, but at predetermined intervals that are constantly decreasing. What is the best way to do this? Is it possible to build this circuit on Arduino, or is it better to make a program on a computer (then through what to send a signal?)

Answer 1

It is possible on arduino, it is possible on a computer through LPT.
Best on an attiny25 or a pic12f629 or similar milliperestral controller.
If a 12V signal should be applied to the relay, then it will be necessary to add transistors, because the controllers work from 5V + relay - a serious load, you can not directly hang it at the feet of the controllers.
A good article on schematics is here: easyelectronics.ru/upravlenie-moshhnoj-nagruzkoj-postoyannogo-toka-chast-1.html

Answer 2

For LPT there is a wonderful program Hiasm. It is a graphical programming environment. You can draw a program in blocks and it will issue the necessary signals to the port. And then 4 resistors, and 4 transistors, for example 2n2222 and 4 any protective diodes. Weekend challenge =)

Answer 3

If this is not a commercial product, then you need to do it on what is more convenient and comfortable. There are many options - from a simple microcontroller or arduino (which would be very easy) to an LPT port.
If a controller, then arduino is usually the easiest option. attiny or junior pic12 is the most compact option.
If the relays do not drive a very large load and are reluctant to load with transistors, then SSR can be used. They can even be switched from LPT.