How to do home electronic projects?
Does it ever happen to you that when you start a circuit you don't know very well what you want it for or what purpose it will have?
This is an important point because, although it is true that sometimes you cannot know in advance what use you are going to give it, it is important to have a certain idea in order to prioritize each step or put more or less effort into each aspect.
- Just for the pleasure of doing it, of overcoming the challenge, seeing that it works and learning along the way
- To see what results and if it is good to go to "production" and install it definitively
- With the idea, from the beginning, to give it real and continued use
Usual process to make an electronic circuit:
- I do the tests as quickly as possible with the sensors that I want to put, one by one, and see if everything works well
- I consider which sensors I am going to combine based on how well I can combine those specific sensors (due to the suitability of the location, available pins, box, etc.)
- I think about what box I am going to put it so that it has a "more or less" professional finish and that they are not a swarm of cables hanging around the house
Although it seems unbelievable, from the previous points, the one that gives me the most headaches is the box. In addition, the box, in many assemblies, is usually an "active" part of the assembly since I use it for circuit wiring.
I like that the things that are "fixed in the house" have a good ending, and I am quite a perfectionist (although many times it remains an intention), so I am never satisfied with the result obtained.
The reality is that I usually say "I leave it like this for the moment, that it is acceptable, and as soon as I have a while I improve it" and, well ... it usually stays like this.
It is clear that when I only want to mess around, and if the design is not very complex, I do it anyway "on the air", on a breadboard or a perfboard.
A practical example of a home electronic project
The best example I can put at the moment is the project I'm finishing and I've already posted some blog posts about its parts: a node for the master bedroom, based on ESPEASY with an infrared emitter to control the air conditioning and a CO2 sensor.
Of course, before doing anything with hardware or firmware you have to do a little research and preliminary decision-making:
- Than functionalities I want him to have the pot?
- How am I going to feed?
- Than components will i use to get these functionalities?
- Am i going to design a box who can 3D print? A standard box?
- How much do i love myself spend?
With all these decisions already made we can get our hands dirty.
Practical execution of the electronic circuit
You know, "Divide and conquer«. Personally, what gives me the best result is to divide the project into several smaller projects that I can do separately.
- Infrared emitter
- CO2 sensor
- Put it all together
I first assembled the circuit with the infrared emitting diodes and tested and adjusted the firmware so that it would work properly independently. Afterwards, and once I was satisfied with the operation of the infrared emitter, I did the same with the CO2 sensor, mounting the hardware and adjusting the firmware so that it worked correctly.
The testing part is very important. Nothing worse than having an apparently finished pot and then realizing that something is wrong. No time to save on tests.
The next important step was box. For this, I started from the standard box that I usually use for most of my assemblies with NodeMCU, and that I print on my 3D printer, but I modified it appropriately in size and added the necessary openings; two for the two infrared LEDs that I was going to use and another two for the two "active" zones of the MH-Z19 sensor that I was going to mount.
The last step: adjust and wire everything inside the box and redo all necessary tests, before installing it in its final location.