[solved] How to identify faulty nrf2401?

Hi,

I bought 4 nrf2401+ and I can’t get them to work for three days with two Arduino Nano. Any idea how to identify a faulty nrf2401?
What I have done so far:

  • I read and followed multiple guides (e.g. this and this) step by step.
  • I tried TMRh20’s RF24 Library, Mirf Library and py-spidev.
  • I soldered a 10µF capacitor between GND/3.3V, I also added a 470µF.
  • I tried using a AMS1117 and LD1117, respectively, to get a smooth 3.3V supply.
    In this regards, have I missed any advice?

What behavior do the modules show?
When using the GettingStarted sketch (TMRh20) I get random noise but no functionality. Funny thing, only one receiver at a time gets the random noise ("Sent response "). When sending (hit “T”), I get a false message of a response (always 0) and a Round-trip time of about 20000 microseconds - no matter if there are other devices active. I tried multiple channels, behavior is the same.
I used pin 7/8 for CE/CSN, also tried 9/10. Checked wiring a dozen times.
When using the SimpleRx/SimpleTx sketchs, I always get “Data Sent Message <incrementinf number 0-9> Acknowledge received” with SimpleTx even when no other module is active. On the SimpleRx, I always get “Data received”.

I’m optimistic that the wiring is exactly like described in the guides. At least I was able to set-up all my other toys, such as a dozen devices (Arduino, Raspberry Pi, ESP) plus two dozen different sensors/modules.

Any idea how to identify a faulty nrf2401? I’ve no oscilloscope but a DMM. Maybe I could try to identify a pattern of pin activities?

UPDATE: Modules were defect.

Thanks & best!

The only way I know to identify a faulty nRF24 is by trying another known good one. I did have one faulty one myself.

You would require a prohibitively expensive oscilloscope to view 2.4GHz signals.

When using the SimpleRx/SimpleTx sketchs, I always get “Data Sent Message <incrementinf number 0-9> Acknowledge received” with SimpleTx even when no other module is active. On the SimpleRx, I always get “Data received”.

Setup my pair of programs again and post several lines of the exact output from both master and slave.

…R

Thanks for your reply. I was hoping for some "the resistance between pin x and y should be z" :-/
Well, looks like I have to order a new batch and test them all until I find a working pair.

Thanks & best!