If you have just purchased a new BS-11, this guide will give you some basic instructions on how to proceed.

Check Package contents

Please check the Packing List and see if you can find all the items in your two boxes.
If there is any doubt, please contact the openbsc mailing list and ask for help.

Unpacking the BS-11

You can now unpack the BS-11 (the heavier box). Make sure you do this with two people handling the unit, 36-48kg of weight
are not meant to be lifted by a single person.

We recommend you mount the wall-mount (from the lighter of the two boxes, packaged in a small brown parcel) to the back of the BS-11,
since this gives it a flat surface. without the wall mount you have a single metal ridge poking out at the back, scratching your floor/table
or other surface.

NOTE: If you want to operate the BS-11 for more than just a bit of testing, especially with an enabled 2nd TRX, you definitely should mount
it vertically to a pole or wall, since this enables airflow through through the cooling fins

Build a power cable

Please follow the instructions at BS11Configuration to manufacture the power cable

Build E1 cable

Please follow the instructions at BS11Configuration to manufacture the E1 cable
from RJ45 to the strange RADIALL twinax connectors

Configure the BS-11 Jumpers

If you remove the connector cover (loosen three Philips screws), you will uncover the four E1 connectors,
as well as the RS232 ports. There are also four green jumpers at the side of the connector panel. The
factory default of those connectors is 75Ohms. You need to remove all of the four jumpers to switch to
120Ohms termination.

Note: The image shows the panel of a working BS11. As you can see, all jumers are removed.

Mount and connect the BS-11 Antenna

The Antenna needs to be attached to the BS11 main unit by the means of four screws. Screws are included in
a small plastic bag.

Connect the four RF antenna cables to the connectors of the BS-11. Their order is 1:1, i.e. leftmost plug into leftmost socket, etc.

Be aware of the fact that the panel antenna adds some gain to the transmission path. So even if you configure the BTS to transmit with the lowest power possible, the effective radiated power (ERP) may exceed permitted limits.

Note: The antenna connectors are formaly known as "N-Connectors"

Test the BS-11 status and configuration

  • connect the power plug to the BS-11
  • connect the RS232 cable to J2 of the BS-11 (see photograph)
  • connect the RS232 cable to your PC
  • switch on the power switch of the BS-11 (the LED should light up green in 2-3 seconds)
  • start the bs11_config program to observe the boot process (see bs11_config for details)
    • you should observe the boot process like it is indicated at the bs11_config page
    • at the end of the process (10 minutes or so), you should have Phase 3 Normal and MBCCU0 Load and Abis-Link Restoring
    • MBCCU1 might be Load or No Load, depending on whether TRX1 is activated or not
      PHASE: 3 Normal               MBCCU0: Load        MBCCU1: No Load     Abis-link: Restoring
  • Once you are in "Phase 3 Normal", use bs11_config query to query the configuration
    • OML TEI must be 25
    • OML E1 Timeslot must be 1 and the full 64kbps timeslot (Full Slot)
              E1 Channel: Port=0 Timeslot=1 (Full Slot)
              TEI: 25
    • It is normal if you see a GET ATTRIBUTE NACK at the end of the output, as the query mode tries to
      query the PA RF Power setting of TRX1 (which by default is not enabled at all).

TEI / E1 timeslot

If your TEI or E1 Timeslot is configured to a wrong value, you can use the following sequence of commands to fix it:

$ ./bs11_config disconnect # you should now be in _State 2 Maintenance_
$ ./bs11_config oml-tei    # you will see a SET ATTRIBUTE ACK and can then terminate the program
$ ./bs11_config reconnect  # brings you back to _State 3 Normal_.
$ ./bs11_config query      # to verify that the setting of E1 Timeslot and TEI is now correct

If you see any other difference (i.e. not reaching Phase 3 Normal or no MBCCU0 Load) please
contact the mailinglist with the full details.

If everything is correct, you can proceed as follows:

PLL Mode

The PLL of the BS-11 can be set to two different modes: # Locked to the E1 clock that is received from the HFC-E1 card # A built-in standalone oscillator

Unless you have some accurate E1 clock source (like a physical ISDN line to a telephone network), we recommend you
configure the PLL Mode to Standalone


$ ./bs11_config disconnect
bs11_config (C) 2009 by Harald Welte and Dieter Spaar


PHASE: 3 Normal               MBCCU0: Load        MBCCU1: Load        Abis-link: Restoring 
PHASE: 2 Maintenance          MBCCU0: Load        MBCCU1: Load        Abis-link: Down      

$ ./bs11_config pll-standalone
bs11_config (C) 2009 by Harald Welte and Dieter Spaar


PHASE: 2 Maintenance          MBCCU0: Load        MBCCU1: Load        Abis-link: Down      
SET ATTRIBUTE [[ObjClass]]=0xa5 [[ObjInst]]=(7,0,0) ACK

E1 Locked

Like above, but using

$ ./bs11_config pll-e1-locked


Preparing the E1 card

HFC-E1 Evaluation Board

  • make sure you configure the jumpers for NT Mode and Termination to 120 Ohms, reference HFC-E1

Note: The image shows a Junghanns HFC-E1 card configured to work with openBSC/BS11

Note: In the picture the JP3 Jumper, which configures the power supply is configured to use the 3,3V power source from the PCI-BUS. If your mainboard does not have a 3,3V power surce your card will refuse to work. If you are unsure, do not touch JP3

Preparing your PC

  • Install a current (>= 2.6.31) Linux kernel source
    • if you have to use an older kernel, Apply the patch from svn trunk/linux-kernel to your kernel
  • Configure the kernel as usual, make sure you enable the mISDN core and driver for HFC-E1 (hfcmulti)
  • Install and boot the kernel, load hfcmulti with dslot=1 module load parameter
  • Check out the latest git version of OpenBSC
  • Compile it
    • You need the following build dependencies: autoconf, automake, gcc, libc6-dev, libdbi-dev, libdbd-sqlite3
      git clone
      cd openbsc/openbsc
      autoreconf -i
    • You may experience compilation problems when you use the latest and greatest trunk version. This is a normal behavior, since OpenBSC is under heavy development. Please contact the mailing list and ask for help in that case.

Getting started under Debian: Building_OpenBSC

Testing the E1 Link

  • connect the RJ45 plug of the E1 cable with your E1 card in the PC
  • connect the two twinax connectors of your E1 cable (correctly!) to the BS-11 connector board, use the two leftmost connectors
  • keep the LMT / RS232 cable connected
  • power-on the BS-11 if it is not already powered-up
  • Start bs11_config and wait until you enter Phase 3 Normal, Abis-Link: Restoring
  • run the "osmo-nitb" program, pass it the '-f ' paramenter for the ARFCN you want to use. Make sure you use a frequency that you have permission to use, and/or limit your output power to a level that you are allowed to transmit. The default ARFCN is 123.
  • Verify that bs11_config now prints Phase 3 Normal, Abis-Link: Up
  • osmo-nitb should print you a lot of yellow lines about setting channel attributes and event state changes
  • at some point you should see 'Bootstrapping RSL'
  • congratulations, your BS-11 should be running and you should see the BCCH (network ID 01-001) from a GSM phone.
Files (4)
TX1.PNG View TX1.PNG 8.34 KB TX1 Antenna Standing Wave Ratio , 04/27/2009 07:56 PM
TX2.PNG View TX2.PNG 8.15 KB , 04/27/2009 07:57 PM
jughanns_E1_openBSC_settings.jpg View jughanns_E1_openBSC_settings.jpg 320 KB dexter, 10/09/2009 01:56 PM
bs-11_panel.jpg View bs-11_panel.jpg 290 KB dexter, 10/09/2009 02:03 PM

Updated by laforge 4 months ago · 24 revisions

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