Im looking for some guidance of daisychaining about 6 arduino Nano's together using only one power source.
As I understand it from what I've read online elsewhere if I feed it from one 9v battery for example into the first Nano (VIN) then take the feed from a 5v pin to a 5v pin on the next nano and so on.
You can certainly daisychain power in the way that you describe as long as the power supply can provide enough current at the required voltage but how far apart are the Nanos
This would make the regulator on the first board dissipate all the excess. If it's just the 5 Nano's, it'll do fine. If you also connect other devices to the same 5V rail, you may end up overheating that regulator. The obvious alternative is the feed al Nano's through their Vin pin with the same 9V.
This ignores obvious issues like:
What would you want to use 5 Nano's for instead of a single, bigger board.
The choice of battery as highlighted above.
The inefficiency of relying on the onboard linear regulators on those boards that will basically burn nearly half the battery capacity in the form of heat.
Maybe take a few steps back: what kind of project do you have in mind? There are probably better ways to approach it.
You can't just connect a coil to an analogue input, because it will inject AC into the Arduino, potentially destroying it. You need some sort of rectification to protect from negative voltages, like a half wave rectifier (single diode) or a full wave rectifier (four diodes). Along with a smoothing capacitor and a resistor to discharge the signal when it is remover from the field. You also need a catcher diode on the positive rail to limit the peak signal to 5V.
It won't be that type of coil. It'll be just a single wire coiled up like a spring to make an antenna. Like an aerial. A single soilid core wire connected to an analogue pin as an input to detect when something is near it. I'm not stupid enough to put an energised coil onto an arduino analogue pin.
So what is "that type of coil". A coil is an inductor.
But that is exactly what you are doing.
From that page:-
EMF meters can also be used by individuals who are concerned about their personal exposure to electromagnetic fields, especially those who suffer from electromagnetic hypersensitivity (EHS).
This is a hysterical response, it is not real. Tests have proved that there is no such thing and it is all physicosematic. Unlike your antenna which can be causing a problem, although the amount of negative signals are probably being caught by the static protection diodes in the processor chip.
The problem is that you have no idea how much current that is inducing in the diodes that have a reputed limit of 1mA, but it could result in early component failure.
So you're saying a project endorsed by Arduino themselves on their project hub is absolute nonsense?
Its an antenna. Far from the point of my topic. Its just an antenna. Be it a single piece of solid core wire or a few twists in it. Only one end is connected to the analogue pin.
The video on the page shows it works so I dont see what your problem is with how I want to attach my single piece of wire to use as an antenna, whether its just a single piece of solid core wire or whether I choose to make it like a spring.
We'll just agree to disagree.
Oh and in answer to your question, this:
DAOKAI 10 PCS Helical Spring Antenna 433MHz Build-In Antenna Copper Solder Bold Copper Spiral Coil 2.2dBi Gain Spring Antenna Direct Welding for Wireless Data Transmission https://amzn.eu/d/08XqqSi9
Yes, there a lot of projects that are less than perfect, and this is one of them. We (most senior contributors) have been trying to get these fixed for decades and still they persist.
A coil is a coil, it is an inductor period, that is the physics of the situation.
You have already made one misguided suggestion as to the powering of the Nanos you have, see post #7, so what makes you believe that you are so right this time.
I have been "doing" electronics since I was 14 years old, I am now 72. I have lectured in Physics at a UK University and worked in industrial and consumer electronics. But no, you know better than me. Do not forget you are actually the one asking for advice.
So what I will do is to put this thread on mute so I will not receive any notifications, and so will not be able to help you anymore. My loss or yours?
Well to be perfectly honest with you I dont really care about Electromagnetic Hypersensitivity. I couldn't really care less if it exists or not. That is not the reason for my project.
The fact is that EMF does exist and this project is a way of building an emf detector.
If I'd have wanted lectures off people about it I would have posted a relevant topic about it.
Somehow people have made this topic about the way I'm attaching the antenna. Be it one of those I linked, a solid copper tube (as in the project listed), or just a single wire attached to the analogue pin. It's an antenna pure and simple. Thats it.
The topic was how to power more than one arduino nano from one power source. It started out OK but has broke down into a slagging match about something the topic isn't about.
Yes, and that's fine. Having said that, I have severe doubts whether the open input of an ADC pin on an ATMega makes for a very dependable EMF detector. I've been playing with something similar lately and it's...temperamental to say the least. Fun to play with, but like I mentioned earlier, it's more suitable as a quasi-random generator than a sensor of some kind. Then again, it'll pick up something alright.
Btw, the question still remains why you'd have 5 Nanos in a string? A Nano has several ADC inputs; why not use a single board and poll the inputs sequentially? Mind you, this approach may affect the readings, since even breathing in the vicinity of the device may make it pick up something. But that's an inherent challenge of this conceptual design to begin with.
