diff --git a/scripts/gnbx.yaml b/scripts/gnbx.yaml
index 28895e7..5799ac7 100644
--- a/scripts/gnbx.yaml
+++ b/scripts/gnbx.yaml
@@ -21,7 +21,7 @@ cu_cp:
 
 
 cell_cfg:
-  dl_arfcn: 628334 # 629668 # 651668 # 500400 # 628334                    # ARFCN of the downlink carrier (center frequency).
+  dl_arfcn: 627000 # 3405 # 629668 # 651668 # 500400 # 628334 # 3425                   # ARFCN of the downlink carrier (center frequency).
   band: 78                            # The NR band.
   channel_bandwidth_MHz: 10           # Bandwith in MHz. Number of PRBs will be automatically derived.
   common_scs: 30                      # Subcarrier spacing in kHz used for data.
@@ -113,6 +113,8 @@ ru_sdr:
   tx_gain: 70
   rx_gain: 50
   lo_offset: 0
+  sync: external
+  clock: external
   expert_cfg:
     low_phy_dl_throttling: 0                # Optional FLOAT (0). Throttles the lower PHY DL baseband generation. Setting to 0 disables throttling. Supported: any value in the range [0 - 1].
     tx_mode: discontinuous                  # Optional TEXT (continuous). Selects a radio transmission mode. Discontinuous modes are not supported by all radios. Supported: [continuous, discontinuous, same-port]