Rack Mounting RTL-SDR

KIMG0533

This post talks about rack mounting a RTL-SDR reciever attached to a raspberry pi into a 1U case. The donor case used was a used kramer broadcast 1110 balanced audio distributor, but any 1U case should work.

Parts Needed:

    • 1U Case
    • 5V 3A power supply (Mean Well RS-15-5)
    • Raspberry Pi
    • Class 10 SD Card
    • rtl-sdr receiver with antenna
    • Short 6″ ethernet patch cable
    • panel mount ethernet jack (“search ebay for “ip68 ethernet”)
    • Screws, wire, fuses, switches, etc…

 

Configuring the Raspberry PI:

    1. Get the Raspbian “lite” image from  https://www.raspberrypi.org/downloads/raspbian/
    2. Install the image based on this guide: https://www.raspberrypi.org/documentation/installation/installing-images/README.md
    3. Find the SD card on the computer and add an empty file to it with the file name “ssh” (no extension). This will enable ssh on boot
    4. Power up the raspberry pi with ethernet connected.
    5. Find the address of the pi by port scanning with a tool like Nmap or looking at your routers DHCP allocation table.
    6. Use a tool like Putty to ssh into the pi on port 23. User name “pi” Password: “raspberry”
    7. Its a good idea to change the password when you log in using the passwd utility
    8. Optional: since this is going to be a headless install it would be a good idea to lower the video memory using  raspi-config.
    9. Now run these commands to get Osmocom rtl-sdr up and running on the pi:
      sudo apt-get update
      sudo apt-get install git cmake build-essential libusb-1.0 libpulse-dev libx11-dev
      git clone git://git.osmocom.org/rtl-sdr.git
      cd rtl-sdr
      mkdir build
      cd build
      cmake ../ -DINSTALL_UDEV_RULES=ON
      make
      sudo make install
      sudo ldconfig
  1. Now you should be able to run rtl_tcp -a IpAddressOfPiGoesHere If an error pop up like Failed to open rtlsdr device #0. run sudo rmmod dvb_usb_rtl28xxu rtl2832 This will prevent the pi from loading the stock drivers for the dongle.
  2. The pi now can be used as a remote rtl-sdr server

Mason Jar Hydroponics

The bucket system from a previous post was difficult to maintain. This was due to the fact that a 5 gallon bucket full of water weighs roughly forty pounds. Hauling that up my basement stairs to change out the water was not a fun task. This lead to trying to find a system that used smaller modular components to grow plants.

Parts Needed:

  • Wide mouth half gallon ball jars
  • Wide mouth plastic ball jar lids
  • 2″ net cups
  • 2″ hole saw
  • Tetra 77851 Whisper Air Pump, 10-Gallon
  • Tubing 1/4″ OD 3/16″ ID. This might be thicker than typical aquarium tubing.
  • Backflow valve
  • T valve
  • Small air stone
  • Rain Bird TS25/10PS Drip Irrigation 1/4″ Tubing Stake with Bug Cap Diffuser
  • rockwool cubes
  • fertilizer
  • 2″ hole saw
  • drill
  • drill bits

Assembly of the ball jar lids is pretty simple. Clamp the lid loosely in a vice and drill a 2″ hole with the hole saw for the net cup. Next drill a smaller hole so you are able to press fit the bug guard from the drip irrigation stakes. This part allows for the air tubing to be press fit into the jars for easy removal. After that plumb up the air pump add some water and the system is ready to grow plants.