diff --git a/src/algorithms/PVT/adapters/rtklib_pvt.h b/src/algorithms/PVT/adapters/rtklib_pvt.h
index 0f1be1a69..3e44c3f36 100644
--- a/src/algorithms/PVT/adapters/rtklib_pvt.h
+++ b/src/algorithms/PVT/adapters/rtklib_pvt.h
@@ -21,6 +21,7 @@
 #ifndef GNSS_SDR_RTKLIB_PVT_H
 #define GNSS_SDR_RTKLIB_PVT_H
 
+#include "gnss_synchro.h"
 #include "pvt_interface.h"           // for PvtInterface
 #include "rtklib.h"                  // for rtk_t
 #include "rtklib_pvt_gs.h"           // for rtklib_pvt_gs_sptr
@@ -77,10 +78,10 @@ public:
         return;
     }
 
-    //! All blocks must have an item_size() function implementation. Returns sizeof(gr_complex)
+    //! All blocks must have an item_size() function implementation
     inline size_t item_size() override
     {
-        return sizeof(gr_complex);
+        return sizeof(Gnss_Synchro);
     }
 
     bool get_latest_PVT(double* longitude_deg,
diff --git a/src/algorithms/observables/adapters/CMakeLists.txt b/src/algorithms/observables/adapters/CMakeLists.txt
index 41323820d..917ef5782 100644
--- a/src/algorithms/observables/adapters/CMakeLists.txt
+++ b/src/algorithms/observables/adapters/CMakeLists.txt
@@ -28,6 +28,7 @@ target_include_directories(obs_adapters
 target_link_libraries(obs_adapters
     PUBLIC
         obs_gr_blocks
+        core_system_parameters
     PRIVATE
         gnss_sdr_flags
         Glog::glog
diff --git a/src/algorithms/observables/adapters/hybrid_observables.h b/src/algorithms/observables/adapters/hybrid_observables.h
index da491131a..9839f0a07 100644
--- a/src/algorithms/observables/adapters/hybrid_observables.h
+++ b/src/algorithms/observables/adapters/hybrid_observables.h
@@ -23,6 +23,7 @@
 #ifndef GNSS_SDR_HYBRID_OBSERVABLES_H
 #define GNSS_SDR_HYBRID_OBSERVABLES_H
 
+#include "gnss_synchro.h"
 #include "hybrid_observables_gs.h"
 #include "observables_interface.h"
 #include <gnuradio/gr_complex.h>     // for gr_complex
@@ -69,7 +70,7 @@ public:
     //! All blocks must have an item_size() function implementation
     inline size_t item_size() override
     {
-        return sizeof(gr_complex);
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/beidou_b1i_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/beidou_b1i_telemetry_decoder.h
index 1ed9b2914..23aeae9d8 100644
--- a/src/algorithms/telemetry_decoder/adapters/beidou_b1i_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/beidou_b1i_telemetry_decoder.h
@@ -25,6 +25,7 @@
 
 #include "beidou_b1i_telemetry_decoder_gs.h"
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
 #include <cstddef>                   // for size_t
@@ -72,7 +73,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/beidou_b3i_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/beidou_b3i_telemetry_decoder.h
index 14860cd67..33c33bebf 100644
--- a/src/algorithms/telemetry_decoder/adapters/beidou_b3i_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/beidou_b3i_telemetry_decoder.h
@@ -23,6 +23,7 @@
 
 #include "beidou_b3i_telemetry_decoder_gs.h"
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
 #include <cstddef>                   // for size_t
@@ -67,7 +68,7 @@ public:
         telemetry_decoder_->reset();
     }
 
-    inline size_t item_size() override { return 0; }
+    inline size_t item_size() override { return sizeof(Gnss_Synchro); }
 
 private:
     beidou_b3i_telemetry_decoder_gs_sptr telemetry_decoder_;
diff --git a/src/algorithms/telemetry_decoder/adapters/galileo_e1b_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/galileo_e1b_telemetry_decoder.h
index c4575fd7d..03b5ce357 100644
--- a/src/algorithms/telemetry_decoder/adapters/galileo_e1b_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/galileo_e1b_telemetry_decoder.h
@@ -26,6 +26,7 @@
 
 #include "galileo_telemetry_decoder_gs.h"
 #include "gnss_satellite.h"
+#include "gnss_synchro.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
 #include <cstddef>                   // for size_t
@@ -76,7 +77,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/galileo_e5a_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/galileo_e5a_telemetry_decoder.h
index 15ea2a905..511863b44 100644
--- a/src/algorithms/telemetry_decoder/adapters/galileo_e5a_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/galileo_e5a_telemetry_decoder.h
@@ -28,6 +28,7 @@
 
 #include "galileo_telemetry_decoder_gs.h"
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
 #include <cstddef>                   // for size_t
@@ -77,7 +78,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/glonass_l1_ca_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/glonass_l1_ca_telemetry_decoder.h
index 7cd8c6cf1..9165fbd94 100644
--- a/src/algorithms/telemetry_decoder/adapters/glonass_l1_ca_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/glonass_l1_ca_telemetry_decoder.h
@@ -25,6 +25,7 @@
 
 #include "glonass_l1_ca_telemetry_decoder_gs.h"
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
 #include <cstddef>                   // for size_t
@@ -71,7 +72,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/glonass_l2_ca_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/glonass_l2_ca_telemetry_decoder.h
index 22c653041..ea318eab3 100644
--- a/src/algorithms/telemetry_decoder/adapters/glonass_l2_ca_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/glonass_l2_ca_telemetry_decoder.h
@@ -24,6 +24,7 @@
 
 #include "glonass_l2_ca_telemetry_decoder_gs.h"
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
 #include <cstddef>                   // for size_t
@@ -70,7 +71,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/gps_l1_ca_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/gps_l1_ca_telemetry_decoder.h
index 462a90c08..047012ab1 100644
--- a/src/algorithms/telemetry_decoder/adapters/gps_l1_ca_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/gps_l1_ca_telemetry_decoder.h
@@ -23,6 +23,7 @@
 #define GNSS_SDR_GPS_L1_CA_TELEMETRY_DECODER_H
 
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "gps_l1_ca_telemetry_decoder_gs.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
@@ -71,7 +72,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/gps_l2c_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/gps_l2c_telemetry_decoder.h
index 411ca2207..7dd549cc4 100644
--- a/src/algorithms/telemetry_decoder/adapters/gps_l2c_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/gps_l2c_telemetry_decoder.h
@@ -23,6 +23,7 @@
 #define GNSS_SDR_GPS_L2C_TELEMETRY_DECODER_H
 
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "gps_l2c_telemetry_decoder_gs.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
@@ -71,7 +72,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/gps_l5_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/gps_l5_telemetry_decoder.h
index 6c5bd5681..8d7d4c433 100644
--- a/src/algorithms/telemetry_decoder/adapters/gps_l5_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/gps_l5_telemetry_decoder.h
@@ -24,6 +24,7 @@
 
 
 #include "gnss_satellite.h"
+#include "gnss_synchro.h"
 #include "gps_l5_telemetry_decoder_gs.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
@@ -73,7 +74,7 @@ public:
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
diff --git a/src/algorithms/telemetry_decoder/adapters/sbas_l1_telemetry_decoder.h b/src/algorithms/telemetry_decoder/adapters/sbas_l1_telemetry_decoder.h
index f7eec1def..45e383f3a 100644
--- a/src/algorithms/telemetry_decoder/adapters/sbas_l1_telemetry_decoder.h
+++ b/src/algorithms/telemetry_decoder/adapters/sbas_l1_telemetry_decoder.h
@@ -24,6 +24,7 @@
 
 
 #include "gnss_satellite.h"  // for Gnss_Satellite
+#include "gnss_synchro.h"
 #include "sbas_l1_telemetry_decoder_gs.h"
 #include "telemetry_decoder_interface.h"
 #include <gnuradio/runtime_types.h>  // for basic_block_sptr, top_block_sptr
@@ -65,27 +66,28 @@ public:
     gr::basic_block_sptr get_right_block() override;
 
     void set_satellite(const Gnss_Satellite& satellite) override;
+
     inline void set_channel(int channel) override { telemetry_decoder_->set_channel(channel); }
+
     inline void reset() override
     {
         telemetry_decoder_->reset();
-        return;
     }
 
     inline size_t item_size() override
     {
-        return 0;
+        return sizeof(Gnss_Synchro);
     }
 
 private:
     sbas_l1_telemetry_decoder_gs_sptr telemetry_decoder_;
     Gnss_Satellite satellite_;
-    int channel_;
-    bool dump_;
     std::string dump_filename_;
     std::string role_;
+    int channel_;
     unsigned int in_streams_;
     unsigned int out_streams_;
+    bool dump_;
 };
 
 #endif