Hi. I built a scoreboard some years back using with an Arduino Uno, a 24V supply, a step down regulator, 15 x TPIC6B5958-bit shift registers, 15 large LED boards with 360'sh led's each. The scoreboard is controlled via a remote that I made using an Arduino Mini Pro, 2 x 1.5V batteries with a voltage doubler circuit which runs on 2.25mA during operation and 0.70uA when asleep.
The signal is transmitted from the remote via an nRF24L01.
This project took me over a year to design, fault find and build - and my forte is not electronics - I'm self taught with help from forums (allaboutcircuits).
The issue I have is the reception. It's a bit hit and miss. If the transmitter / receiver was along stronger it would be better, however it also has to deal with batteries and "rough users".
I'd like to make it transmit via a phone. I have someone who said he could create an app for me on an android that we can keep in the soccer pavilion. However, I'd like some suggestions on how to tackle the wifi side. I've read somewhere the idea of adding a ethernet shield, a wifi range extender on the board and in the club room. I possibly need a transmit range of say 200 to 300m max.
Can someone either point me to a similar project they think would be worth looking at, or suggesting what equipment I'd need to test it at home with another arduino - maybe just trying to blink the LED light remotely. Thanks in advance. Again, please remember I'm a novice, so go easy please on technical terms.
I actually made 2 scoreboards and remotes. One is on channel 116 and the other is on 108. At the time I did try a few different frequencies, but it didn't seem to make much difference.
But I really don't really like the unreliability of this setup and dependance on a remote. I'd rather another method if at all possible.
So effectively you want to create a new project that has a mobile phone talking to a receiver of some kind 300m away.
I doubt that using a single WiFi range extender pair that uses the 2.4/5GHz range will give you the 300 meter range your require. More realistically you will need a series of repeaters, at which point this becomes an infrastructure project that the venue will need to install and pay for. Once this infrastructure exists then an EPS32 or similar board can act as the receiver talking to whatever hardware you currently have.
Without the WiFi repeater network then another option is to use a cellular modem complete with SIM card and a service provider contract.
If you are OK with the complexity then another alternative would be to use an arrangement like the following.
Mobile phone WIFI -> adjacent ESP32 receiver with LORA transmitter -> LORA receiver with adjacent Ardiuno.
First time I've heard of LoRa and I've watched quite a few videos on it. Seems like in Australia I can only legally use one with a frequency of 915MHz to 928MHz.
On some videos they said even though these devices are know to have a range of even up to 100Km, they only were able to do 400 to 500m. Another chap tested one from his house driving to a petrol station about 1.5Km away and it worked.
There was some discussion of it only transmitting low amounts of data, however all I need to do is change one digit at a time, so I assume it should be ok for this???
Have you used this setup before? Is there any particular brand receiver and transmitter modules that I should use (I'm not sure if one brand is better than the other)?
In Australia the 915MHz to 928MHz spectrum is allocated to LoRaWAN which needs a pre-defined set of send and receive channels for communication with base stations.
For your application you probably don't need to update the score board more than once per second so you can go for the max spreading factor which will give you plenty of range margin.
If you had a couple of ESP32's (with the external antenna jack) and set them up with these, you'd probably be good for miles. (The aiming will be critical.)
Sure, but then you exceed the legal transmit power.
Given the audience and the company funding this forum it's best to only suggest solutions that are 100% legal.
Its the ERP/EIRP that gets you in trouble.
For example, From Australia
"In Australia, we use the 915-928 MHz frequency range with a maximum Equivelant Radiated Isotropic Power (EIRP) of 1 watt. In general, if you use AU915 compliant LoRaWAN modules, you will be complying with the standard."
The antenna connections are really flimsy and that's one reason I think they keep failing.
Yes, the scoreboard only needs to be updated at a minimum of 1 second apart.
Could you let me know if there any particular brand receiver and transmitter modules that I should use (I'm not sure if one brand is better than the other)? Also a list of what I'd need in relation to the transmission / receiving signal? Ta.
All I give you is a list of the stuff that I would use and the assumption is that the person carrying the mobile phone is always within 10 meters of the ESP32 and Lora transmitter. In practice this means carrying the project box with you. A transparent food container is fine providing you keep it out of the sun. Also this is assumed to be a 3.3v project.
Starting at the mobile phone end you need an "ESP32 WROOM-32D" dev board, not the bare module. The D model has a built-in antenna and you are looking for one where the antenna is poking out from the rest of the PCB, otherwise the extra capacitance reduces the antenna efficiency. I get mine from Aliexpress and they are about $AU12 including shipping which takes about 3 weeks. A common problem with these is having one or more mis-labelled GND pins , so you need to check to see which pins are connected to the metal USB shell and therefore ground.
The ESP32 needs to be configured as a "WiFi Access Point" (WAP) with a unique SID of your choosing that the mobile phone can connect to.
The ESP32 is connected via SPI to a LoRa module such as the 433MHz version I mentioned earlier. They are expensive, but they are supported by Adafruit who provide good documentation, tutorials and a help forum.
You also need a 433MHz antenna with coax. Don't use a 2.4GHz WiFi antenna, it won't work well. Position the LoRa antenna well away from the ESP32.
The receiving LoRa module is a replica of the transmitter. This is connected via SPI to a 3.3v Arduino of some kind. (You don't need WiFi at the receiving end.)
