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Topic: NRF24L01 Transmission Problem (Read 1 time)previous topic - next topic

alb12

#15
May 16, 2018, 05:03 pm
Ok, and If I change the antenna of node 1 ( 2db ) by antenna of 8 or 12 db ?

Robin2

#16
May 16, 2018, 05:23 pm
Ok, and If I change the antenna of node 1 ( 2db ) by antenna of 8 or 12 db ?
I don't understand.   I thought you said you cannot change the nRF24.

And I always get my decibels mixed up - is 8 more or less powerful than 2?

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

MarkT

#17
May 16, 2018, 05:47 pm
There is no such thing as an omnidirectional antenna with gain.  Its a beaming antenna so you
must point it right for best signal.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

alb12

#18
May 16, 2018, 07:16 pmLast Edit: May 16, 2018, 07:45 pm by alb12
Yes for the node 31, but if I change the antenna of node 1 ( See my Schema ).
Normally 8db is more powerful than 2db

Robin2

#19
May 16, 2018, 08:39 pm
Yes for the node 31, but if I change the antenna of node 1 ( See my Schema ).
Sorry. I feel I am being really dumb here. I thought you said earlier that Node1 is the node with the high-power Arduino?

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

alb12

#20
May 16, 2018, 10:10 pmLast Edit: May 16, 2018, 10:10 pm by alb12
Yes Node 1 is the nRF24L01 + PA +LNA like this ( http://img.dxcdn.com/productimages/sku_222913_1.jpg ) with antenna 2db

And the Node 31 has the nRF24l01 "classic"  ( http://img.dxcdn.com/productimages/sku_149483_1.jpg ), solder on PCB like this ( http://domotique-diy.over-blog.com/2018/05/domotiser-un-appareil-grace-a-un-relai-v2.html )

Robin2

#21
May 16, 2018, 11:05 pm
Yes Node 1 is the nRF24L01 + PA +LNA like this ( http://img.dxcdn.com/productimages/sku_222913_1.jpg ) with antenna 2db
And what can you do to get 8dB?

Quote
And the Node 31 has the nRF24l01 "classic"
Looking at the picture of the PCB with the nRF24 attached I wonder if the arrangement of parts interferes with the wireless signal propagation. In the projects I have built I have made sure that there is no metal very close to the antenna - even though I have not been building long-range projects.

And I can't remember if you said whether you have experimented with changing the orientation of your module (and hence the antenna) relative to Node1? IIRC correctly the flat face of the antenna should face the direction you want the signal to go.

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

#22
May 17, 2018, 07:59 am

@alb12, do not cross-post.  Threads merged.

alb12

#23
May 17, 2018, 09:43 am
Yes, that's why the PCB is cut behind the antenna so that it's better.
If I change the position of antenna it's not really better.
In both cases, the node 31 often received but the node 1 doesn't receive the value of node 31

For the 8db, I can change on Node 1 by this antenna link

Robin2

#24
May 17, 2018, 09:55 am
I have no idea whether a different physical antenna would improve things. The matching of 2.4GHz wireless transceivers to antennas is far far beyond my pay grade.

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

#25

Robin2

#26
May 17, 2018, 11:05 am
I still don't understand why you are not putting the unit with the external antenna at the distant location.

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

alb12

#27
May 17, 2018, 11:16 am
Because with external antenna at the distant location, I have the same result.

Robin2

#28
May 17, 2018, 12:15 pmLast Edit: May 17, 2018, 12:22 pm by Robin2
Because with external antenna at the distant location, I have the same result.
I don't recall that you mentioned that earlier.

I must say I am surprised that you are having problems - the distances are not huge.

Is the Node1 nRF24 hidden behind something that might be absorbing the wireless signal? Or close to something else that is using 2.4GHz wireless - such as Bluetooth or WiFi?

Try the second example in this Simple nRF24L01+ Tutorial just between the devices you are calling Node1 and Node31 - i.e. no attempt at networking. If it was my project I would also try that code between Node0 and Node 31 - i.e. the two low-power units. I would also do some range tests between two units outdoors.

Which brings to mind another thought - have you swapped Node0 with Node31 in case the device at Node31 is not performing properly.

...R
Two or three hours spent thinking and reading documentation solves most programming problems.

alb12

#29
May 17, 2018, 12:40 pmLast Edit: May 17, 2018, 12:44 pm by alb12
Yes the Node 1 is in attic with a nearby wifi repeater .
Also I haven't defined setPALevel on any Node

I haven't swape Node 0 and Node 31

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