Doomsday messenger - 3

Printed PCBs arrived, soldered the rfm95 chip and the gsm antenna on it with normal headers and now everything works nicely and is solid as well...

tested the range, and i can receive messages in a clear line of sight with a range of 2.5 kms+ or more wasn't able to test longer because 💀noida seems to have very less places with a clear line of sight near my home atleast... (cars and metro stations don't really matter they were in b/w my testing range... but huge buildings do block signals)

Doomsday messenger - 2

I tested the range with two laptops and was able to send and receive messages with 200 ft in height and 150 m in horizontal range... wasn't able to do in a distance of 1km so I will have to use a gsm antenna for that now...

Now the whole setup is too wonky with the wires hanging

and the wire antenna doesn't really do justice... so I bought two gsm antennas and now I'm designing a pcb on which i will solder the rfm chip + attach the antenna and the pcb will have a 2.54 mm pitch so that its easy to attach...

dm me if anyone needs the gerber files for this pcb... i've sent this for printing will get it in 15 days... until then ill start writing the code for the node discovery etc and get rid of this crude way of sending messages...

i still have to think about how in the future i want to communicate with it, by which i mean, if i wanna add a keyboard + display to it... or if i want it to host a hotspot with a website so that we can send msgs via phone etc... kinda confused...

Doomsday messenger - 1

Ok so the LoRa chip should have headers on it, otherwise you'll have to solder them... now its a pretty weird chip, its not meant for breadboard prototyping

so breadboards have a pitch of 2.54 mm and this has a pitch of 2 mm so it wont fit... you gotta solder the headers and then solder some wires so that you can use it... (had to learn soldering and it took a while)

the connections to make for reference

thanks to this project page that helped me so much

now for the initial coding part, i'm writing this in arduino since tinygo doesn't support wifi and the rfm library is very old... so there's this library called LoRa by Sandeep Mistry and it does the job great...

https://github.com/Shubhaankar-Sharma/doomsday-messenger/tree/update-1 here's the initial code to send messages via the terminal

Doomsday messenger - update 0

I wanted to dabble a bit in electronics and so I thought of building a LoRa (long range radio communication) based device that can send and receive messages also creates a mesh network that enables messages to bounce from node to node increasing range...

So I already have some progress

Things I bought / you need to create this project...

• 2 esp32-wrooms (i mean you need everything twice so that you can test it out)
• 2 LoRa RFM95W-868S2R (basically any rfm 9x works, but 868 means that it operates on 868 Mhz, there's three frequency that don't require a radio license, and its based on your country, for europe and india its 868, for NA its 915 and rest 433 ig)
• 2/4 bread boards 💀 the esp is too wide, so for prototyping either you let one side hang or join two breadboards, so i got 4 so that i can build on seperate huge breadboards
• male to male pins
• 2 mm headers... ( will explain later)