RTL-SDR + SDR Radio + Funcube Sat = Fun!

Nov 23

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With the recent record number of cubesat launches this month most  Amateur Radio enthusiasts been busy, myself included. There hasn’t been a better time to get into receiving these satellites. With the inexpensive hardware,  free software,  a ton of information and an active community it is “easy” and quite a thrill to get into this hobby.

I will focus on one satellite and one method of receiving and decoding in this post. There are so many ways to do this but I think this method is the least expensive and provides really good results.

You will need:

  1. RTL-SDR Dongle – E4000 or R820T model (I prefer the R820T model and they are the easiest to find now)
  2. SO-239 Pigtail adapter for the Dongle – This is great if you don’t want to cut and solder on a connector like I did!
  3. Zadig Drivers – For the RTL-SDR USB
  4. RTL-SDR Libraries for SDR-Radio.com V2 software – Choose SDR-Radio.com.RTLUSB-20130209.zip
  5. SDR-Radio.com V2 Software – I used the November 15th, 2013. Version 2.1 build 1571
  6. Good receiving antenna – 2m Yagi, Quadrifilar Helicoidal (QFH), Ground Plane,etc
  7. VB-Cable Driver – Virtual Audio cable (Center Column)- NOTE: Please Donate if you use it. As a bonus once you donate you get to download A and B Channels.  I am glad I did, the extra channels are nice to have!
  8. Funcube Dashboard Software
  9. Time to put it all together!

The total cost depending on what antenna you have or choose to build can be between $11 to whatever. Very minimum investment is required to receive and decode the funcube telemetry. This is fantastic for everyone, especially those on a budget that would like to experience this hobby first hand. If there are any educators reading this please take the time to show your students how much fun this can be. After all, it is part of the funcube mission!

I must say this as well: if you can afford to buy a Funcube Dongle, please do! It has better performance than the RTL-SDR and the money goes back to funding the funcube initiatives, like the Funcube satellites.

On to the setup:

I won’t go into detail on each and every install. Please read the pages I linked above for further instructions.

  1. Install SDR-Radio.com V2 Beta
  2. Plug RTL-SDR USB Dongle into computer
  3. Install ZaDig Drivers – NOTE: You may need to click Options and then List All devices. Select Bulk-in, (Interface 0) then click the replace Driver button.
  4. Extract and Copy the three  RTL-SDR DLL’s for SDR-Radio.com V2. NOTE: Overwrite existing files in the SDR-Radio.com’s directory and use the correct architecture!
  5. Install VB-Cable Virtual Audio Interface
  6. Install the Funcube Dashboard

Configuration:

 SDR-Radio.com V2:

  1. Launch SDRConsole (V2)
  2. On the Home Tab click the Select button from the Radio Group
  3. Click Definitions
  4. Click Search and Select the RTL SDR (USB) Option. If that option does not exist please check to make sure you copied the correct DLL’s into the SDR-Radio.com Program Folder
  5. Click Yes on the 1 Entry Found alert and Click OK
  6. Highlight the new entry (ezcap USB2.0 DVB-T/DAB/FM Dongle)
  7. Click Start
  8. Tune into a known frequency like the National Weather Service, this is required to adjust the PPM
  9. On the Home tab again, click the Radio Configuration button
  10. Click the + or – buttons to adjust the PPM. For example one of my dongles is +82 and the other is -133 so they vary widely.
  11. Click the more options selection and click the Internal AGC box. (You can experiment with this, mine worked better with it on)
  12. Select the frequency to 145.927 Mhz and set the Mode to SSB Data-U OR Wide-U, it doesn’t seem to matter
  13. Drag the bandwidth bar out to 24000 Hz to get full coverage. Note: This is required so you don’t have to “chase” the satellite because of the doppler effect, Funcube will always be in the bandwidth coverage. The Funcube Dashboard will Autotune on the transmission. (See screenshots)
  14. On the VFO-A box Click the Audio dropdown (next to the little audio speaker)
  15. Click the Playback device and Select VB-Cable for the output – Took me a while to find this one!!!
  16. For satellite data you can use whatever you are used to but the SDR-Radio’s works great. The current satellite number is 2013-066B and is likely to change to AO-73 in future TLE’s

Funcube Dashboard

NOTE: Be sure to register at the Funcube Data Warehouse to be able to submit your decoded packets automatically. If you ONLY want to decode and not send you can still use the software but not contribute. The more contributors the better though!

  1. Click File; then Settings
  2. Select the Audio Tab and select the Input Device as the Cable Output VB-Audio
  3. Click the Warehouse Tab and fill in your Site ID, Auth Code and click the Stream data to warehouse and Click Save
  4. Click Capture from the Menu and select Capture from Soundcard
  5. On the tuning panel change the High Value to 24000 and make sure the Auto Tune check box is checked
  6. You should see a sudden drop off in the tuning window around 24000 hz (See screenshots)

Final Thoughts:

This should get you started on receiving and sending the telemetry back to the funcube data warehouse. There are other great options out there like Analog receive to Souncard, Funcube Dongle but this seems to be the most inexpensive to get started. Now that you have your station setup for the Funcube you can go chase other sat’s as well!  There are other folks doing much more that I am and have great resources available. Please visit the links sections for more information.

I hope this helps you get started and most importantly have FUN!

 Other Links:

I/Q Data and Audio files:

  • Audio from 21 Nov 2013 0352 UTC Pass – Telemetry Only:

Download: 21-Nov-2013-3052UTC-Pass-Telemetry

  • Audio From the 24 Nov 2013 0436 UTC Pass during Active Transponder:

Download: 23-Nov-2013-232647 145.958300 MHz

Screen Shots:

All Working together
Real-time Telemetry Decoding
Data Warehouse contribution shoutout
Funcube Doppler
FunCube AO-73 with Active Transponder – I/Q file available in Post

Posted on November 23, 2013, in Digital, Satellites, SDR, Software. Bookmark the permalink. 2 Comments.

  1. Drew | February 23, 2014 at 10:10 pm

    Would you consider letting AMSAT reprint this in the Journal?

    Reply

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