[geri12]

Here again. Still I will build the weather station. I am programmer, and today NRF24l01 device was applied to other projects (PA+LNA version, 300 meters smoothly bridged with him). I thought, about what would happen, if nrf24l01 I would use, instead of the 433MHz couple. Final PCB is not yet, only program modification... It would be worth? I think at first, it is better reception is over 300m. (Only NRF24l01+PA+LNA version!) Two-way reception. It would be an advantage for me in the future. (development) Sorry...Bad English. I hope I was clear.

[werk_ag]

Hi geri12,

Keep us informed about your progress. Any development is welcome.
Does your modified code run on an Arduino Nano?
Can it deal with multiple TX units? Two-way communication may not be very useful for this matter.

[geri12]

Hi

Oks. This week you can modify the program. I use atmega644 (with arduino sketch). If the program memory is enough for the ATmega328, Arduino Nano can also be run. Multiple TX units not problem. Easy to do...

[werk_ag]

Hi jeri12,

I always encourage any development or modification that everyone wants to do with the WeatherDuino Pro2 for it's own use, but that doesn't mean that I will gonna work on someone's code.
In this particular case, I really haven't the intention to change the type of RF link between the TX and RX units. There are several reasons for this, one of them is very important to me: backward compatibility!
There are around two hundreds of WeatherDuino Pro2 installations, I think that users will appreciate this concern. Despite the several enhancements introduced along the years, current software still work with early hardware boards.
By other way, almost all brands of weather stations, still use simple, one way RF links.

[geri12]

I'm sorry, I not well drafted. I change program. (obviously) I've been thinking, and I understand. Unfortunately the current hardware is not compatible with the NRF units. So it's not a serial protocol (1 pin), SPI protocol it uses (5 pin). Existing ones should not be changed. (not worth) WeatherDuino Pro2 software is so wonderful. At me....Distance from the 433MHz transmitter me little. I should add amplifiers. EBay is available... Before buying the idea came. In addition, It would be a secondary station. (Soil moisture, leaf wetness, UV, solar radiation, and 5, 20, 100cm moisture temperature measurement) I can plan (for example, the NRF RF module). So for me this is the case. If there is something, I share with you.

[werk_ag]

Of course that what I said doesn't mean that some parts of the WeatherDuino system will not evolve at some point in the future, but backward compatibility with existing systems should always be a concern, and assured as much as possible.

For special situations, the RF coverage range of the used 433Mhz modules can be greatly expanded using RF amplifiers. Recently I tested one of those amps, which can easily reach 1Km (3Km according to manufacturer) in open space. Doing this with one way RF links, it's easier.

I'm pleased that you appreciate the WeatherDuino software, it represent countless hours of work, and it's free to everyone.

I can plan (for example, the NRF RF module). So for me this is the case. If there is something, I share with you.

I think that will not be too hard adapt the code to use the NRF24 module. As it uses SPI, you may need to change some pins currently used. Possibly (I'm not sure) the Arduino library for the NRF24 and the required changes will increase the code size beyond the Arduino Nano limit, but as you intend to use an atmega644, this shouldn't be a problem.

[uncle_bob]

Just a side note that this months' (September) SiliconChip magazine has a reader submitted short "Circuit ideas" article using NRF2401s' transceivers on ATMEGA328P microprocessors. The author says he get 1.5km with a BiQuad antenna.

[Shred]

I bought a few of the cheap NRF24l01 modules a couple of years ago and found the range was terrible in "real world" conditions. The modules were ok outside, but as soon as a wall was placed in the way, range dropped dramatically.

Lower frequencies generally penetrate obstactles better. The NRF24l01 modules are on 2.4GHz, but don't have the advantage of the exotic modulation techniques used by WiFi systems operating in that unlicensed band. Using an amplifier will get you more range, but may be illegal (it is in Australia, where I live) and/or cause harmful interference to other users of the 2.4GHz band.

I think the RFM95 / RFM96 range of LoRa radios sound promising as a way of getting much better range, without large antennas or contributing to the interference problems on unlicensed radio bands.

https://tronixlabs.com.au/wireless/lora/...australia/

[werk_ag]

Shred, I fully agree with you. The 2.4Mhz don't seems to me the route to follow. If I ever think about changing the WeatherDuino Pro2 RF modules, probably the choice will be the RFM96. They allow to choose the operating frequency according to the legislation of each country, and there is even an high power version.

[geri12]

Hi!

I have done it. I use RF24L01. The transmitter power setting under 10mW. (It's legal... plenty) My country allowed maximum power is 100mW. (2,4Ghz band). I talked to other "diy builders", and they are also used this unit (PA+LNA version) without any problems. Non-interference in other devices (game controller, keyboard, mouse, etc...).

Otherwise... I used two months of 433MHz transmitter with amplifiers, but the 2.4GHz is better. (me)