====== Operating instructions ======
original source(([[https://docs.google.com/document/d/1KzPZJW0ErInFtfTCmhNhSZTOpg6N2bgZDyIxkh_DRVs/pub?1532944531#h.iubpod4vxyrx|Documentation System BLUE]], chapter 3))

If the boards are built up, the first test should proceed as follows.

  - Do not connect any preamplifier, do not connect a GPS antenna, and do not connect the network cable. Connect only the 5 volt USB power supply to the mainboard.
  - On the mainboard some LEDs should flicker and the buzzer should make some noise. If no LED is lit and no sound is heard, then something is wrong with the voltage supply. Check whether a switch is installed and whether it must be turned on, and check Jumper S1. Pin 5 and 6 have to be connected. This Jumper is only available on the boards up to Version 19.3c. At board 19.4 the power jumper has to be closed, see Section 2.2.
  - After switching on, the red GPS LED should flash. Now connect the GPS antenna and wait until the red GPS LED turns off. If the LED is not blinking after some time, or slightly later, the blue LED should blink. If this is the case, the GPS module works well.
  - Next connect the network cable to your DHCP. The network connectors has two LEDs, a green one and a yellow one. The green LED should light continuously. The yellow LED should flicker. If this is the case, then the network connection can be tested. Try to connect with the webserver of the board. Go to the web page of the router and look for the IP address of the board. The hostname of the board is "blitzortung". Enter the IP address of the board in the address line of your browser. Then the firmware webpage should be shown.