Dreamcatcher Chat Application


Well could such a software be part of the install image and then update itself over the Outernet network to the latest releases?
So users will be able to install it straight away when connected to the Wi-Fi?
Maybe a menu link on front/index webpage?


Unfortunately it’s not that simple. In order to be useful as a transmitter, it would need higher power levels, so an amplifier would be required. We would also need to add filters. And as an intentional radiator, it would need a very specific type of certification. Right now we sell the device as a receiver that can also be used as LoRa development board. We would like to eventually support the user case you described, but it won’t come along with just an over the air update.


I see, just reading the "User’s Guide to Setting Up and Using Outernet Dreamcatcher v 3.02Q
With Skylark 5.1 (As of March 29, 2018)"

and l like:

  • 2 micro plugs for charging and be
    an uninterruptible power supply if the primary charging source goes away
  • the Dreamcatcher’s WiFi Hotspot, you need to be within 10 feet of the
    device because the Dreamcatcher’s WiFi Hotspot is not very powerful.
    But if connected Dreamcatcher to Your Local Router by WiFi as a Client
    the device could still act as a server and offer users option to install chat
    client for various OS platforms (Android, Windows, Linux etc.) and once
    connected in “Client mode” no need to modify the above you mentioned :slightly_smiling_face:

also looking at the main website

outernet = "Use cases include radio broadcasting, emergency alerts, and educational content delivery."
outernet = slow satellite connection …

so please correct me if I am wrong, the target audience is not people that already have Internet access via Dial up, xDSL, Satelite or mobile GPRS,EDGE,HSDPA, HSxxx,LTE but people that do not have Internet access so remote parts of world, possible in maritime use (I would love to take Lantern with me on the cruise liner :smile: ) or areas that have been hit by and I quote

Disaster - when reliable communication is most important

So this device would only be of use if during the disaster the information is beamed down Outernets network subject to Outernets satellite coverage in the area as well, but having locally running server on the Dreamcatcher/Lantern hardware and being build into Skylark that would allow users communicate with each other that would be a huge bonus and selling point?


@Syed would it be possible to update the normal software for the outernet board to include the chat application?


@jason_matonis Here is as far as I go building the Chat app.
Installed dependency apps —
sudo apt install libtool libtool-bin pkg-config

Got to the part of configuring libsoc and ran into trouble
snip/paste from the readme>
How do I build libsoc?

libsoc uses the autotools build system. A script called autogen.sh is
included to setup the build. Exact steps:

  1. ./autogen.sh
  2. ./configure [–disable-debug] [–enable-board=]
  3. make

–disable-debug : disables the debug code, turn off the debug to get
the fastest operation but at the cost of any debug
print outs. Ommiting this flag will leave debug
–enable-board : install board specific GPIO pin mappings file. This
enables the use of the libsoc_board_gpio_id function
to look up GPIO ID’s based on how the pin is named for
a supported board. Supported board can be found under

This is where I couldn’t figure out which board name to fill in, The list of board_files are
beaglebone, bubblegum, chip, dragonboard,hikey . I tried them all no machine was
example – for the using hikey board

[email protected]:~/Packet-Tester/Packet-Tester/libsoc$ sudo ./configure [–disable-debug] [–enable-board=hikey]
configure: WARNING: you should use --build, --host, --target
configure: WARNING: invalid host type: ]
configure: WARNING: you should use --build, --host, --target
configure: WARNING: invalid host type: ]
checking build system type… Invalid configuration ]': machine]’ not recognized
configure: error: /bin/bash config/autoconf/config.sub ] failed


No, that chat application is not supported by us and requires Armbian.


What is the error when you choose chip as the board?


Assuming the 1240-1300 Ham band, for lower power levels up to 1 watt, MMICs are available.

Chebyshev filters limit harmonics. A filter design program should tell us how many poles we need.

We would have to look into the specs for part 97 certification for a Ham-band transceiver, if it were manufactured. Individual hams are open to roll their own

Tons of LoRaWAN boards are available for the 433 and 915 MHz bands under part 15 regulations. They are very limited due to the very low power levels and lots of other users in the unlicensed bands.

It’s this use case that I’m interested in exploring further. There’s of course more needed to make this whole thing run as a system like T/R switching, possibly an LNA for receive, and some SWR foldback protection in case the antenna fails, etc.

But opening up what is in DreamCatcher to let people develop it as a LoRa receiver and later as a LoRa transceiver is an exiting area to explore, especially in the ham bands where more transmit power is allowed. But you can do an awful lot with 100 mW, considering the link budget.

That’s understandable. Understanding that the market is there and that DreamCatcher is not that far away is basically what I’m pointing out.

–Konrad, WA4OSH


I didn’t realize I couldn’t do anything in Skylark. It wasn’t until I found this page that it made it clear. http://rxos.readthedocs.io/en/develop/getting_started/what_is_rxos.html

I don’t want to take the DC offline to test, perhaps I can run Armbian in virtualbox and see what it looks like.


I now have two DC’s (v3.03) working. Has anyone got the Chat app installed using armbian and configured?

I don’t mind having to turn off my Skylark and swap in different operating system SD. Looking others that are trying this new app.


I have a DC 3.02Q and a DC 3.03. I’ve not tried it yet. I’m still brainstorming.

Once Chat is up and running, the next steps are to build a gateway to local 9600 Baud packet / APRS network on 440.800 MHz (or on 1200 Baud on 2M). I can then chat with other people and get them interested in LoRa on 1.2 GHz.

On the client side, a small wireless keyboard/mouse pad would work nicely for sending the chat text.

With a GPS chip/dongle, it could send APRS location sentences back to the APRS i-Gateway. This way, I can do range testing.

I have yet to connect to WetNet or understand what is required to build a Gateway.

–Konrad, WA4OSH


My initial goal would be to send a sms type message between the DC’s then have the DC’s act as a wifi access point to somehow?? have a real time message system or allow a keyboard to keyboard style client interface. — lot’s work to be done…

But like you… I have yet got DreamcatcherChat up and running.


@ac8dg @Konrad_Roeder @unixpunk @clavo @Gavin_Groce

So, there were some problems with compiling on the chat app on the 4.14 kernel. That’s been resolved now, but no need to even bother since you can just run the executable in the directory where the file is located.

sudo ./chat

The only variable you can change is the output frequency. We’ll have a later version that will allow all parameters to be adjusted, such as bandwidth, coding rate, spreading factor, packet size, and mixer current.

Running the chat application literally takes 10 seconds now. If you only have one Dreamcatcher, you can still see the LoRa packets with an RTL-SDR.


What is the proper wget command to download the chat program into the DC once it’s connected to Wi-Fi? I tried variations of this. It’s connecting to the FTP server, but my path is not correct.

wget https://raw.githubusercontent.com/Outernet-Project/Dreamcatcher-Packet-Tester/DreamcatcherChat/chat

–Konrad, WA4OSH


git clone instead of wget

git clone https://github.com/Outernet-Project/Dreamcatcher-Packet-Tester


Good so far
$ sudo ./chat
This what got the first time I ran it.
(note to others you must chmod +x chat after the git clone)

 Dreamcatcher Chat (v.0.0 alpha)

Pin was declared as input
Pin was declared as input
Pin was declared as input
Pin was declared as input
Select operating frequency (MHz):

second time I ran it >>> went straight to the Select frequency.

now I am just waiting some signals.

@Syed which sma radio connector should be used for Chat ? I see the lnb-on led is not lit, the rf_tx led2 flashed, the led5 busy flashes, and led6 packet flashes… and direct led1 is on (probably answered my question)


Yep! It works. The signals you are waiting on must be generating from another Dreamcatcher running the application at the same frequency.


@ac8dg Since the application leverages the mixer, you’ll need to use the LNB-SMA. The Direct-SMA outputs directly from the SX1281 and bypasses the mixer.


One more question for today, I have several other lora modulated esp32/sx1276 boards, but I would like to know the “default” SF and C/R that the DC is using. I guess I also need to know if the lnb-sma is filtered before the mixer section. (ie what freq range is it sensitive to)


There is no filtering on Dreamcatcher.

The default on chat application found in main.cpp appear to be:

modulationParams.PacketType                  = PACKET_TYPE_LORA;
modulationParams.Params.LoRa.SpreadingFactor = LORA_SF7;
modulationParams.Params.LoRa.Bandwidth       = LORA_BW_0400;
modulationParams.Params.LoRa.CodingRate      = LORA_CR_4_5;

PacketParams.PacketType                 = PACKET_TYPE_LORA;
PacketParams.Params.LoRa.PreambleLength = 0x08;
PacketParams.Params.LoRa.HeaderType     = LORA_PACKET_VARIABLE_LENGTH;
PacketParams.Params.LoRa.PayloadLength  = 50;
PacketParams.Params.LoRa.Crc            = LORA_CRC_ON;
PacketParams.Params.LoRa.InvertIQ       = LORA_IQ_INVERTED;