nRF24L01+PA+LNA

[AWI]

@dzairo Better to be safe ;-)

[doblanch]

@AWI That's clear then.... I didn't know that 5V on uno can draw 450ma... ON their website, they precise only I/O and 3.3V... From now it's very clear. I will use the 5V pin, with "something" to reduce it to 3.3V...
I have this in stock : http://www.ebay.com/itm/Mini-3A-DC-DC-Converter-Adjustable-Step-down-Power-Supply-Module-replace-LM2596s-/261328784505?ssPageName=ADME:L:OU:FR:3160
a power down module, IN="5V" OUT-"adjustable (including 3.3V)"
Do you know for the nano the +5V max draw ?
Thank for your help, grandly appreciated.

[AWI]

@doblanch The Nano has an 78M05 regulator, should be able to supply 500mA (including the power for the MCU and FTDI chip, So more than enough power to power your step-down. Let us know if your problem is solved.

[doblanch]

@AWI Hello, I put a stepdown module on the both end, added a capacitor. I change the myconfig.h file to put RF24_PA_MAX on RF24_PA_LEVEL and RF24_PA_LEVEL_GW . The result was a little bit better, I'm not even sure :-( . But from now, result are good, I switch back my current antenna by the original one delivered with the module NRF24+.
in fact, I installed some big antenna (I have some spare with my routed wifi network), but I think it was a mistake. With the NRF24 bulk antenna, it works really better, I have some others tests to do...I will keep you informed in the coming days. thanks again for you help

[wico2002]

Hi, i have the same problem. Bought a pa+lna radio with black antenna and only work if i touch the antenna or the radio's pcb, else the data if not sent at all. i added only a 200uf capacitor. Even with the breadboard power supply, to have a separate 3.3v it dont work. My basic nrf24l01+ is working well (except the range) but not the pre amplified one.

Any one have ideas ?

[Oitzu]

@wico2002 try adding a layer of plastic wrap followed by a layer of tin foil around the pcb.
In this process don't let the tinfoil touch the pcb or any connection. This will basically create a farraday cage around your pcb.
I've learned the hard way that the boosted modules can sometimes, at high power levels, interfere with itself.

[wico2002]

@Oitzu I try running it at a lower PA level, set in the code, don't know if it helped or not. I also found if I keep the antenna straight (my antenna plug is pointing on the side, so let say 0 degrees) or at 90 degrees no data is sent but if it is fold at 45 degree the data seems to be sent good even if I don't touch the radio (but still don't know if I got a good range or not). seems to work better without the antenna plugged in ...

i'll try your trick

[Oitzu]

@wico2002 that's all really the typical behaviour i observed, too.
In reality the module sends the data but will never receive the "ack" because the signal overloads, due to interferences, the nrf24l01+ on the board.
Holding your hand arround the pcb or antenna or unplugging the antenna weakens the signal and stops this behaviour.

See also: http://forum.mysensors.org/topic/1877/2-x-nrf24l01-pa-lna-with-rf24_pa_max/12

[wico2002]

Thank you for this link.

I will reply in that topic to continue the same subject.

[johnr]

Hi,

I built my serial gateway like two years ago and it is running smooth with nRF24L01+ PA+ LNA

I remember a had to fiddle with the power setting. Since I am now replacing it with a Ethernet gateway, I plan to use a ld1117v33 to power the radio. It can give 800ma so it should be suffcient to runt it without power issues.

Did anyone have experience with this? Do you recommend I should set Pa_level to high or Max?

[Oitzu]

@johnr you should give it a try. 800mA is more than enough.
But don't forget to shield the module probably otherwise you will have the above mentioned interferences.

Site note: The max setting is actually a special setting for nrf24l01+ clones that have a higher output setting on a special register then the original nrf24l01+ chips. But regardless the chip you can use this. A original nrf24l01+ will simply ignore the register flag.

[karl261]

@Oitzu Is that so? How could I find out if my nrf accepts the max setting? Maybe it is not using it at all. What is the default then? I also saw that @GertSanders was recommending to use the "high" setting as maximum. Maybe that is why?

[Oitzu]

@karl261 the MAX Setting is the HIGH setting + a extra bit. The extra bit is ignored by the original nrf24l01+ chips. Some nrf24l01+ clones (also known as the SI24R1) are using this bit to switch into a higher mode.

[karl261]

@Oitzu Ok, so, if I understand correctly, then, if I set the nrf to max, and it will ignore the flag, it will be at high, correct?

Another question: I have a battery sensor with a +pa+lna because I installed a little weather station in a bird house... Concerning battery life, would you run it at min or low?

[Oitzu]

@karl261 with the original nrf24l01+ modules this is correct, yes.
To save battery use the lowest setting that still works without transmitting errors.