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Topic: Poor Man's 2.4 GHz Scanner (Read 86981 times) previous topic - next topic

amdkt7

I'm not seeing anything that I understand, the output after the details output looks like this:
000000000000000011111111111111112222222222222222333333333333333344444444444444445555555555555555666666666666666677777777777777
0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcd
000000000000000000000000000000000000000000000000000012233332431000000000000000000000000000000000000000000000000000000000000000
000000000000000000000000000000000000000000000000000022232344442000000000000000000000000000000000000000000000000000000000000000
000000000000000000000000000000000000000000000000000123223445420000000000000000000000000000000000000000000000000000000000000000

I'm using the latest library from TMRh20 2014, as near as I can tell. Arduino IDE 1.8.5.

It's not matching the sample output displayed earlier in the thread, and I see nothing that indicates channel numbers.

My goal is to find a low traffic channel to use, of course. Thanks

liuzengqiang

Same here :)

I just fired up my nRF24 module for the first time since I got them some years ago. From what I gathered in the code, the first and second row simply indicates that there are 126 columns, representing 126 nRF24 channels (I guess). Then the rest of the rows are signal strength received in each channel. From your data, signal is strong around channels 0x40 to 0x4A and no signal in other channels.
Serial LCD keypad panel,phi_prompt user interface library,SDI-12 USB Adapter

amdkt7

That output is too hard to read! I have experimented with the code and used it to test single channels. I found that it could barely detect a radio within four feet. I have since abandoned the simple modules and moved all the way to the shielded modules with amplifiers, so revisiting the scanner sketch would be a good idea. I'm sure I could create an easier to understand output.

Thanks for your reply.

liuzengqiang

You need a wider screen size to contain all 126 characters in one line. Then it would be easy to understand. Yeah, I bet the PCB trace antenna is too weak for any realistic situation. I have two modules that have SMA connectors. I attached 2.4GHz WiFi antennas to the modules. There's quite a lot of chatter that my module picked up. The module with the library seems to be able to do half-duplex communication fine. You have to have a way to decide who's talking and who's listening, like using walkie-talkie, I imagine. I'm interested in finding radios that are full-duplex with actual device addresses so the sender can receive from multiple sources while sending simultaneously, so I can do point-to-multi-point with one receiver and multiple senders, like using zigbees but only cheaper, much cheaper ;)
Serial LCD keypad panel,phi_prompt user interface library,SDI-12 USB Adapter

amdkt7

Just now saw this, Yahoo keeps deciding what is spam for me, and I keep finding stuff I missed in there.

A wider screen makes sense. I tend to boost the font size up so that I can see and that probably messed it up for me.

I still have not revisited the scanner app, busy with other parts of my project. I do have a transmitter out in the yard sending in the temperature and the humidity every four seconds reliably. Those $1 cheapies are not good enough for that.


liuzengqiang

I have some modules with external antenna and amplifier. They work alright. I didn't test their ranges. I also have the cheap ones. They tend to have very limited ranges. More tests are needed.
Serial LCD keypad panel,phi_prompt user interface library,SDI-12 USB Adapter

amdkt7

Yeah, the cheap on board antenna's are very limited in range. Maybe a good antenna mod would be workable, but the amplifier helps a lot too. I have not fully tested the range of ones that I have settled on, it has the shield. I can go anywhere on my property while the receiver is in the house, and that is good enough for me. I'm using the lowest power setting. You need a strong power supply to keep stable power for higher power settings. It's not easy, and the cheap switchmode wall warts can be tough to get to work in that situation.

cepics

Hi, I'm quite confuse reading the output....
I did the test, moving the poor men's scanner in my office, searching for a free channel for my project

this is the output:

Code: [Select]
Starting Poor Man's Wireless 2.4GHz Scanner ...

Channel LayStarting Poor Man's Wireless 2.4GHz Scanner ...

Channel Layout
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|    .                    RWW        .   .                       | 7
|   :        ::          RWRR*                                   | 5
| . .        aW*  .      ====.            .                      | 10
| .       .  -            +Wa           ..                       | 13
| :::  : :     :  :       Wa            :                        | 4
|    . ..  .             :RWW.       . ..                        | 11
| :          +: :        WW++            ::                      | 4
| . .        ..: .       WRRR            .                       | 8
|         ..   ...       :W-+-:     ..   .                       | 14
| .    .. .....::.  .....=WWWWR       . .                        | 19
|     ...    .:-..       -WR*a+      ..                          | 9
| .           .:-.      .WWWW.      .                            | 8
|   ..      ...  ..      :.=W:      .    .                       | 7
|       :       W        :a:           : +                       | 4
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|     .-        W .       --+                                    | 6
|  .   .     ...W         ::          . .                        | 11
|   .       . ..W.   .    ..                                     | 22
|             ..W .                                              | 20
|               W .                                              | 15
|            ...W                                                | 20
|             ..W                                                | 30
|               W .                                              | 24
|             :.W ..                                             | 31
|              -W...                                             | 24
|           .-.:W.:: .                                           | 19
|          ..==-W ..                                             | 36
|              .W...                                             | 35
|        ..... .W.......    ...  .....                           | 26
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|       .. .....W...    ..... .......                            | 44
|              .W...                                             | 51
|             ..W ..                                             | 50
|           ...-W:..                                             | 60
|            ..:W...                                             | 56
|             ..W...                                             | 57
|            ...W ..                                             | 58
|               W...                                             | 51
|               W...    .. ..                                    | 39
|            -..W --     .... .                                  | 26
|         .... :W......   ... .. . .                             | 43
|       .....  -W...... ...............                          | 34
|   .   . ... .-W:....................                           | 28
|       .....:==W.......  .............                          | 40
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|       .. ...=+W .         ..         .                         | 29
|            .-=W...        ...                                  | 33
|    ....... ...W...                                             | 35
|             ..W.:.                                             | 19
|        .. ....W -:                                             | 22
|           ....W....   ..........   .                           | 38
|       ........W...    .. .   ..    ..                          | 39
|       .. ..=+*W....   .....   ....                             | 55
|       .. ..-+=W.+- .. ..... .......                            | 18
|       .....::-W...... ..............                           | 48
|       ......::W.....................                           | 46
|       ........W...... ..............                           | 46
|       .....-:+W-....... .............                          | 56
|         ...==+W..:..... .............                          | 35
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|            ...W.     .. .. ..   .                              | 49
|            ...W.::....     ... ..   .                          | 27
|            ...W.         .                                     | 24
|        ..   . W--...             .   .                         | 13
|            .. :        -W=..      .    .                       | 11
|           . . *   .    .+W*-  ..      .                        | 6
|             ..W  .      :.             .                       | 11
|           .-==W..                                              | 30
|           ....W...                                             | 41
|           -+*aW-                                               | 101
|          .:*aaW:                                               | 61
|          .=***W-..                                             | 60
|          .-++*W=..                                             | 91
|         ..:=++W-.                                              | 72
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|..   ..  ..-::-W-..                                            .| 54
|.        ..:--+W+..                                             | 67
|           :::aW+..                                             | 53
|          .:==WW*..                                             | 50
|          .:--*Wa..                                             | 48
|         ..--:+W+..                                             | 59
|         ...::-W..                                              | 44
|         ...:::W...                                             | 57
|         .:::--W-.                                              | 50
|         .-=+==W-:.                                             | 48
|         ..:---W:..                                             | 46
|         .:----W...                                             | 40
|         ...=--W: .                                             | 51
|    .    :+aRaRWR+.                                             | 110
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <
|         ..-==RWa..                                             | 78
|         .-aRRWa+.   . .                                        | 101
|         .:=++RWR-.                                             | 94
|          :=+:+W*.                                              | 77
|          ...:*W+..                                             | 63
|            .=aW*..                                             | 68
|            ++RW+.                                              | 80
|           .*+RW+.                                              | 86
|           .+*WW=..                                             | 85
|           .+aRW-..              ..                             | 76
|      ....-=WRaR-.....     .                                    | 70
|         ...R+-W=.                                              | 66
|         .-+Ra*W+.                                              | 77
|         .:RWR=W=...     ....                                   | 80
>      1 2  3 4  5  6 7 8  9 10 11 12 13  14                     <


in my project, I'm using the "RF24.h" library

which channel have I to set in myRadio.setChannel() argument?

tnk a lot

srza

Sorry for this basic question but can someone suggest a "terminal application" that I could use to view this please?
I'm generally not that familiar with using my terminal.
I'm looking at the Arduino IDE serial monitor and it looks like its cascading lines of somethings but all in one big line which I cant seem to change with the "new line" box. In any case I get the feeling I'm not supposed to be using the serial monitor .
Any help much appreciated.. I'm trying to make a rudimentary Wifi scanner to demonstrate something,

Thanks for this code too!

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