Re: Error With GPSDO USRP x300

[Marcus D. Leech]

On 22/02/2023 18:14, Jones, James (jtjones49) wrote:

Hello, I have a USRP x300 and I am trying to use the GPS module for clock sync. I am running Ubuntu 20 and am using external GPS antennas and am using GNUradio version 3.10.5.1 . I have the following arguments for the USRP source block:

Sync: Unknown PPS

Time Source: Default

Clock Source: O/B GPSDO

However, when running this block I get the following error:

Traceback (most recent call last):

  File "/home/.../Documents/test.py", line 290, in <module>

    main()

  File "/home/.../Documents/test.py", line 268, in main

    tb = top_block_cls()

  File "/home/.../Documents/test.py", line 92, in __init__

    self.uhd_usrp_source_0_0.set_clock_source('gpsdo', 0)

RuntimeError: RuntimeError: Reference Clock PLL failed to lock to gpsdo source.

Any help is appreciated and thank you to Marcus Müller for helping me resolve the incompatibility with the USRPs.

James Jones

    Oh, also, if there's a source connected to the external REF IN
    connector, try disconnecting it.  On at least *some* hardware
      versions the external clock input can interfere with the on-board
    GPSDO clock.