diff --git a/vna_system/api/endpoints/health.py b/vna_system/api/endpoints/health.py
index f7fc5b3..12c11f6 100644
--- a/vna_system/api/endpoints/health.py
+++ b/vna_system/api/endpoints/health.py
@@ -32,12 +32,7 @@ async def health_check():
 async def device_status():
     """Get device connection status and details."""
     acquisition = singletons.vna_data_acquisition_instance
-    device_info = acquisition.get_device_info()
 
     return {
-        "device_info": device_info,
         "acquisition_running": acquisition.is_running,
-        "last_sweep": acquisition.sweep_buffer.get_latest_sweep_number(),
-        "total_sweeps": len(acquisition.sweep_buffer.get_all_sweeps()),
-        "buffer_stats": acquisition.sweep_buffer.get_stats(),
     }
\ No newline at end of file
diff --git a/vna_system/api/main.py b/vna_system/api/main.py
index 914f0e7..fda7b9c 100644
--- a/vna_system/api/main.py
+++ b/vna_system/api/main.py
@@ -13,7 +13,7 @@ from pathlib import Path
 
 import vna_system.core.singletons as singletons
 from vna_system.core.processing.sweep_processor import SweepProcessingManager
-from vna_system.api.websockets.websocket_handler import WebSocketManager
+from vna_system.core.processing.websocket_handler import WebSocketManager
 from vna_system.api.endpoints import health, processing, web_ui
 from vna_system.api.websockets import processing as ws_processing
 
@@ -66,10 +66,10 @@ async def lifespan(app: FastAPI):
 
         # Start acquisition 
         logger.info("Starting data acquisition...")
-        singletons.vna_data_acquisition_instance.start()
-
         # Connect processing to acquisition
         singletons.processing_manager.set_sweep_buffer(singletons.vna_data_acquisition_instance.sweep_buffer)
+        singletons.vna_data_acquisition_instance.start()
+
         singletons.processing_manager.start()
         logger.info("Sweep processing started")
 
diff --git a/vna_system/config/config.py b/vna_system/config/config.py
index 5800627..b8bfb31 100644
--- a/vna_system/config/config.py
+++ b/vna_system/config/config.py
@@ -5,8 +5,12 @@ Configuration file for VNA data acquisition system
 
 import glob
 import logging
+from pathlib import Path
 import serial.tools.list_ports
 
+# Base directory for VNA system
+BASE_DIR = Path(__file__).parent.parent
+
 # Serial communication settings
 DEFAULT_BAUD_RATE = 115200
 DEFAULT_PORT = "/dev/ttyACM0"
@@ -46,7 +50,7 @@ SERIAL_PEEK_SIZE = 32
 SERIAL_IDLE_TIMEOUT = 0.5
 SERIAL_DRAIN_DELAY = 0.05
 SERIAL_DRAIN_CHECK_DELAY = 0.01
-SERIAL_CONNECT_DELAY = 0.5
+SERIAL_CONNECT_DELAY = 0.01
 
 
 def find_vna_port():
@@ -61,21 +65,21 @@ def find_vna_port():
     # Method 1: Use pyserial port detection by VID/PID
     try:
         ports = list(serial.tools.list_ports.comports())
+
         logger.debug(f"Found {len(ports)} serial ports")
 
         for port in ports:
-            logger.debug(f"Checking port {port.device}: VID={port.vid:04X} PID={port.pid:04X} "
-                        f"Manufacturer='{port.manufacturer}' Product='{port.description}'")
-
+            logger.debug(f"Checking port {port.device}")
+            
             # Check by VID/PID
             if port.vid == VNA_VID and port.pid == VNA_PID:
-                logger.info(f"Found VNA device by VID/PID at {port.device}")
+                logger.debug(f"Found VNA device by VID/PID at {port.device}")
                 return port.device
 
             # Fallback: Check by manufacturer/product strings
             if (port.manufacturer and VNA_MANUFACTURER.lower() in port.manufacturer.lower() and
                 port.description and VNA_PRODUCT.lower() in port.description.lower()):
-                logger.info(f"Found VNA device by description at {port.device}")
+                logger.debug(f"Found VNA device by description at {port.device}")
                 return port.device
 
     except Exception as e:
diff --git a/vna_system/core/acquisition/data_acquisition.py b/vna_system/core/acquisition/data_acquisition.py
index cc49bd8..6e4bd11 100644
--- a/vna_system/core/acquisition/data_acquisition.py
+++ b/vna_system/core/acquisition/data_acquisition.py
@@ -6,11 +6,10 @@ import os
 import struct
 import threading
 import time
-from typing import BinaryIO, List, Optional, Tuple
+from typing import BinaryIO, List, Tuple
 
 import serial
 
-# Avoid wildcard imports: make config access explicit and discoverable.
 from vna_system.config import config as cfg
 from vna_system.core.acquisition.sweep_buffer import SweepBuffer
 
@@ -21,25 +20,16 @@ logger = logging.getLogger(__name__)
 class VNADataAcquisition:
     """Main data acquisition class with asynchronous sweep collection."""
 
-    def __init__(self, port: str = None, baud: int = cfg.DEFAULT_BAUD_RATE) -> None:
+    def __init__(self) -> None:
         self.bin_log_path: str = cfg.BIN_LOG_FILE_PATH
 
-        # Auto-detect port if not specified
-        if port is None:
-            self.port: str = cfg.get_vna_port()
-            logger.info(f"Using auto-detected port: {self.port}")
-        else:
-            self.port: str = port
-            logger.info(f"Using specified port: {self.port}")
-
-        self.baud: int = baud
+        self.baud: int = cfg.DEFAULT_BAUD_RATE
 
         self._sweep_buffer = SweepBuffer()
-        self.ser: Optional[serial.SerialBase] = None
 
         # Control flags
         self._running: bool = False
-        self._thread: Optional[threading.Thread] = None
+        self._thread: threading.Thread | None = None
         self._stop_event: threading.Event = threading.Event()
 
         # Sweep collection state
@@ -76,7 +66,6 @@ class VNADataAcquisition:
             self._thread.join(timeout=5.0)
             logger.info("Acquisition thread joined.")
 
-        self._close_serial()
 
     @property
     def is_running(self) -> bool:
@@ -88,99 +77,25 @@ class VNADataAcquisition:
         """Return a reference to the sweep buffer."""
         return self._sweep_buffer
 
-    def get_device_info(self) -> dict:
-        """Get information about the connected VNA device."""
-        info = {
-            'port': self.port,
-            'baud_rate': self.baud,
-            'is_connected': self.ser is not None and self.ser.is_open if self.ser else False,
-            'is_running': self.is_running,
-            'device_detected': False,
-            'device_details': None
-        }
-
-        # Try to get device details from port detection
-        try:
-            from serial.tools.list_ports import comports
-            for port in comports():
-                if port.device == self.port:
-                    info['device_detected'] = True
-                    info['device_details'] = {
-                        'vid': f"0x{port.vid:04X}" if port.vid else None,
-                        'pid': f"0x{port.pid:04X}" if port.pid else None,
-                        'manufacturer': port.manufacturer,
-                        'product': port.description,
-                        'serial_number': port.serial_number
-                    }
-                    break
-        except Exception as e:
-            logger.debug(f"Could not get device details: {e}")
-
-        return info
-
     # --------------------------------------------------------------------- #
     # Serial management
     # --------------------------------------------------------------------- #
 
-    def _connect_serial(self) -> bool:
-        """Establish the serial connection."""
-        try:
-            logger.info(f"Attempting to connect to VNA device at {self.port} @ {self.baud} baud")
 
-            # Check if port exists
-            import os
-            if not os.path.exists(self.port):
-                logger.error(f"Port {self.port} does not exist. Device not connected?")
-                return False
-
-            # Check permissions
-            if not os.access(self.port, os.R_OK | os.W_OK):
-                logger.error(f"No read/write permissions for {self.port}. Try: sudo chmod 666 {self.port}")
-                logger.error("Or add your user to the dialout group: sudo usermod -a -G dialout $USER")
-                return False
-
-            self.ser = serial.Serial(self.port, baudrate=self.baud, timeout=0)
-            time.sleep(cfg.SERIAL_CONNECT_DELAY)
-            self._drain_serial_input()
-            logger.info(f"Serial connection established to {self.port}")
-            return True
-        except PermissionError as exc:
-            logger.error(f"Permission denied for {self.port}: {exc}")
-            logger.error("Try: sudo chmod 666 {self.port} or add user to dialout group")
-            return False
-        except serial.SerialException as exc:
-            logger.error(f"Serial connection failed for {self.port}: {exc}")
-            return False
-        except Exception as exc:  # noqa: BLE001 (keep broad to preserve behavior)
-            logger.error(f"Unexpected error connecting to {self.port}: {exc}")
-            return False
-
-    def _close_serial(self) -> None:
-        """Close the serial connection if open."""
-        if self.ser:
-            try:
-                self.ser.close()
-                logger.debug("Serial connection closed.")
-            except Exception:  # noqa: BLE001
-                # Preserve original behavior: swallow any serial close errors.
-                logger.debug("Ignoring error while closing serial.", exc_info=True)
-            finally:
-                self.ser = None
-
-    def _drain_serial_input(self) -> None:
+    def _drain_serial_input(self, ser: serial.Serial) -> None:
         """Drain any pending bytes from the serial input buffer."""
-        if not self.ser:
+        if not ser:
             return
 
         drained = 0
         while True:
-            bytes_waiting = getattr(self.ser, "in_waiting", 0)
+            bytes_waiting = getattr(ser, "in_waiting", 0)
             if bytes_waiting <= 0:
                 break
-            drained += len(self.ser.read(bytes_waiting))
+            drained += len(ser.read(bytes_waiting))
             time.sleep(cfg.SERIAL_DRAIN_CHECK_DELAY)
         if drained:
-            logger.debug("Drained %d pending byte(s) from serial input.", drained)
+            logger.warning("Drained %d pending byte(s) from serial input.", drained)
 
     # --------------------------------------------------------------------- #
     # Acquisition loop
@@ -190,80 +105,78 @@ class VNADataAcquisition:
         """Main acquisition loop executed by the background thread."""
         while self._running and not self._stop_event.is_set():
             try:
-                if not self._connect_serial():
-                    time.sleep(1.0)
-                    continue
+                # Auto-detect port
+                self.port: str = cfg.get_vna_port()
+                logger.info(f"Using auto-detected port: {self.port}")
 
-                with open(self.bin_log_path, "rb") as raw:
-                    buffered = io.BufferedReader(raw, buffer_size=cfg.SERIAL_BUFFER_SIZE)
-                    self._drain_serial_input()
-                    self._process_sweep_data(buffered)
+                with serial.Serial(self.port, self.baud) as ser:
+                    self._drain_serial_input(ser)
+                    with open(self.bin_log_path, "rb") as raw:
+                        buffered = io.BufferedReader(raw, buffer_size=cfg.SERIAL_BUFFER_SIZE)
+                        self._process_sweep_data(buffered, ser)
 
             except Exception as exc:  # noqa: BLE001
                 logger.error("Acquisition error: %s", exc)
                 time.sleep(1.0)
-            finally:
-                self._close_serial()
 
     # --------------------------------------------------------------------- #
     # Log processing
     # --------------------------------------------------------------------- #
 
-    def _process_sweep_data(self, f: BinaryIO) -> None:
+    def _process_sweep_data(self, f: BinaryIO, ser: serial.Serial) -> None:
         """Process the binary log file and collect sweep data one sweep at a time."""
-        while self._running and not self._stop_event.is_set():
-            try:
-                # Start from beginning of file for each sweep
-                f.seek(0)
+        try:
+            # Start from beginning of file for each sweep
+            f.seek(0)
 
-                # Validate header
-                header = self._read_exact(f, len(cfg.MAGIC))
-                if header != cfg.MAGIC:
-                    raise ValueError("Invalid log format: MAGIC header mismatch.")
+            # Validate header
+            header = self._read_exact(f, len(cfg.MAGIC))
+            if header != cfg.MAGIC:
+                raise ValueError("Invalid log format: MAGIC header mismatch.")
 
-                self._reset_sweep_state()
+            self._reset_sweep_state()
 
-                # Process one complete sweep
-                sweep_completed = False
-                while not sweep_completed and self._running and not self._stop_event.is_set():
-                    # Read record header
-                    dir_byte = f.read(1)
-                    if not dir_byte:
-                        # EOF reached without completing sweep - wait and retry
-                        logger.debug("EOF reached, waiting for more data...")
-                        time.sleep(0.1)
-                        break
+            # Process one complete sweep
+            sweep_completed = False
+            while not sweep_completed and self._running and not self._stop_event.is_set():
+                # Read record header
+                dir_byte = f.read(1)
+                if not dir_byte:
+                    # EOF reached without completing sweep - wait and retry
+                    logger.debug("EOF reached, waiting for more data...")
+                    time.sleep(0.1)
+                    break
 
-                    direction = dir_byte[0]
-                    (length,) = struct.unpack(">I", self._read_exact(f, 4))
+                direction = dir_byte[0]
+                (length,) = struct.unpack(">I", self._read_exact(f, 4))
 
-                    if direction == cfg.DIR_TO_DEV:
-                        # TX path: stream to device and inspect for sweep start
-                        first = self._serial_write_from_file(f, length)
+                if direction == cfg.DIR_TO_DEV:
+                    # TX path: stream to device and inspect for sweep start
+                    first = self._serial_write_from_file(f, length, ser)
 
-                        if not self._collecting and self._is_sweep_start_command(length, first):
-                            self._collecting = True
-                            self._collected_rx_payloads = []
-                            self._meas_cmds_in_sweep = 0
-                            logger.info("Starting sweep data collection from device")
+                    if not self._collecting and self._is_sweep_start_command(length, first):
+                        self._collecting = True
+                        self._collected_rx_payloads = []
+                        self._meas_cmds_in_sweep = 0
+                        logger.info("Starting sweep data collection from device")
 
-                    elif direction == cfg.DIR_FROM_DEV:
-                        # RX path: read exact number of bytes from device
-                        rx_bytes = self._serial_read_exact(length, capture=self._collecting)
-                        self._skip_bytes(f, length)  # Keep log file pointer in sync
+                elif direction == cfg.DIR_FROM_DEV:
+                    # RX path: read exact number of bytes from device
+                    rx_bytes = self._serial_read_exact(length, ser, capture=self._collecting)
+                    self._skip_bytes(f, length)  # Keep log file pointer in sync
 
-                        if self._collecting:
-                            self._collected_rx_payloads.append(rx_bytes)
-                            self._meas_cmds_in_sweep += 1
+                    if self._collecting:
+                        self._collected_rx_payloads.append(rx_bytes)
+                        self._meas_cmds_in_sweep += 1
 
-                            # Check for sweep completion
-                            if self._meas_cmds_in_sweep >= cfg.MEAS_CMDS_PER_SWEEP:
-                                self._finalize_sweep()
-                                sweep_completed = True
+                        # Check for sweep completion
+                        if self._meas_cmds_in_sweep >= cfg.MEAS_CMDS_PER_SWEEP:
+                            self._finalize_sweep()
+                            sweep_completed = True
 
-            except Exception as exc:  # noqa: BLE001
-                logger.error("Processing error: %s", exc)
-                time.sleep(1.0)
+        except Exception as exc:  # noqa: BLE001
+            logger.error("Processing error: %s", exc)
+            time.sleep(1.0)
 
     def _finalize_sweep(self) -> None:
         """Parse collected payloads into points and push to the buffer."""
@@ -320,7 +233,7 @@ class VNADataAcquisition:
                 raise EOFError(f"Unexpected EOF while skipping {n} bytes.")
             remaining -= len(chunk)
 
-    def _serial_write_from_file(self, f: BinaryIO, nbytes: int) -> bytes:
+    def _serial_write_from_file(self, f: BinaryIO, nbytes: int, ser: serial.Serial) -> bytes:
         """
         Stream *nbytes* from a file-like object to the serial port.
 
@@ -343,9 +256,7 @@ class VNADataAcquisition:
             # Write to serial
             written = 0
             while written < len(chunk):
-                if not self.ser:
-                    break
-                n = self.ser.write(chunk[written:])
+                n = ser.write(chunk[written:])
                 if n is None:
                     n = 0
                 written += n
@@ -354,29 +265,27 @@ class VNADataAcquisition:
 
         return bytes(first)
 
-    def _serial_read_exact(self, nbytes: int, capture: bool = False) -> bytes:
+    def _serial_read_exact(self, nbytes: int, ser: serial.Serial, capture: bool = False) -> bytes:
         """Read exactly *nbytes* from the serial port; optionally capture and return them."""
-        if not self.ser:
-            return b""
 
         deadline = time.monotonic() + cfg.RX_TIMEOUT
         total = 0
         out = bytearray() if capture else None
-        old_timeout = self.ser.timeout
-        self.ser.timeout = min(cfg.SERIAL_IDLE_TIMEOUT, cfg.RX_TIMEOUT)
+        old_timeout = ser.timeout
+        ser.timeout = min(cfg.SERIAL_IDLE_TIMEOUT, cfg.RX_TIMEOUT)
 
         try:
             while total < nbytes:
                 if time.monotonic() >= deadline:
                     raise TimeoutError(f"Timeout while waiting for {nbytes} bytes.")
-                chunk = self.ser.read(nbytes - total)
+                chunk = ser.read(nbytes - total)
                 if chunk:
                     total += len(chunk)
                     if capture and out is not None:
                         out.extend(chunk)
             return bytes(out) if (capture and out is not None) else b""
         finally:
-            self.ser.timeout = old_timeout
+            ser.timeout = old_timeout
 
     # --------------------------------------------------------------------- #
     # Parsing & detection
diff --git a/vna_system/core/acquisition/sweep_buffer.py b/vna_system/core/acquisition/sweep_buffer.py
index 9f45ae8..c37519f 100644
--- a/vna_system/core/acquisition/sweep_buffer.py
+++ b/vna_system/core/acquisition/sweep_buffer.py
@@ -1,16 +1,9 @@
-#!/usr/bin/env python3
-"""
-Sweep data structures and buffer management for VNA data acquisition.
-
-This module contains classes for storing and managing sweep data in a thread-safe manner.
-"""
-
 import math
 import threading
 import time
 from collections import deque
 from dataclasses import dataclass
-from typing import List, Tuple, Optional, Dict, Any
+from typing import List, Tuple
 
 from vna_system.config.config import SWEEP_BUFFER_MAX_SIZE
 
@@ -55,35 +48,11 @@ class SweepBuffer:
             self._buffer.append(sweep)
             return self._sweep_counter
 
-    def get_latest_sweep(self) -> Optional[SweepData]:
+    def get_latest_sweep(self) -> SweepData | None:
         """Get the most recent sweep"""
         with self._lock:
             return self._buffer[-1] if self._buffer else None
 
-    def get_sweep_by_number(self, sweep_number: int) -> Optional[SweepData]:
-        """Get a specific sweep by its number"""
-        with self._lock:
-            for sweep in reversed(self._buffer):
-                if sweep.sweep_number == sweep_number:
-                    return sweep
-            return None
-
-    def get_all_sweeps(self) -> List[SweepData]:
-        """Get all sweeps currently in buffer"""
-        with self._lock:
-            return list(self._buffer)
-
-    def get_buffer_info(self) -> Dict[str, Any]:
-        """Get buffer status information"""
-        with self._lock:
-            return {
-                'current_size': len(self._buffer),
-                'max_size': self._buffer.maxlen,
-                'total_sweeps_processed': self._sweep_counter,
-                'latest_sweep_number': self._buffer[-1].sweep_number if self._buffer else None,
-                'oldest_sweep_number': self._buffer[0].sweep_number if self._buffer else None,
-                'next_sweep_number': self._sweep_counter + 1
-            }
 
     def set_sweep_counter(self, sweep_number: int) -> None:
         """Set the sweep counter to continue from a specific number."""
diff --git a/vna_system/core/processing/base_processor.py b/vna_system/core/processing/base_processor.py
index 14900c0..d5f27ec 100644
--- a/vna_system/core/processing/base_processor.py
+++ b/vna_system/core/processing/base_processor.py
@@ -6,7 +6,7 @@ Base sweep processor interface and utilities.
 from __future__ import annotations
 
 import abc
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict
 
 from vna_system.core.acquisition.sweep_buffer import SweepData
 
@@ -26,7 +26,7 @@ class BaseSweepProcessor(abc.ABC):
         pass
 
     @abc.abstractmethod
-    def process(self, sweep: SweepData) -> Optional[ProcessingResult]:
+    def process(self, sweep: SweepData) -> ProcessingResult | None:
         """Process a sweep and return results."""
         pass
 
@@ -43,8 +43,8 @@ class ProcessingResult:
         processor_name: str,
         sweep_number: int,
         data: Dict[str, Any],
-        plotly_figure: Optional[Dict[str, Any]] = None,
-        file_path: Optional[str] = None,
+        plotly_figure: Dict[str, Any] | None = None,
+        file_path: str | None = None,
     ) -> None:
         self.processor_name = processor_name
         self.sweep_number = sweep_number
diff --git a/vna_system/core/processing/processors/magnitude_plot.py b/vna_system/core/processing/processors/magnitude_plot.py
index 86f4f45..c7868ab 100644
--- a/vna_system/core/processing/processors/magnitude_plot.py
+++ b/vna_system/core/processing/processors/magnitude_plot.py
@@ -7,7 +7,7 @@ from __future__ import annotations
 
 import os
 from pathlib import Path
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Any, Dict, List, Tuple
 
 import numpy as np
 import matplotlib.pyplot as plt
@@ -38,7 +38,7 @@ class MagnitudePlotProcessor(BaseSweepProcessor):
     def name(self) -> str:
         return "magnitude_plot"
 
-    def process(self, sweep: SweepData) -> Optional[ProcessingResult]:
+    def process(self, sweep: SweepData) -> ProcessingResult | None:
         """Process sweep data and create magnitude plot."""
         if not self.should_process(sweep):
             return None
@@ -107,7 +107,7 @@ class MagnitudePlotProcessor(BaseSweepProcessor):
 
         return fig
 
-    def _save_matplotlib_image(self, sweep: SweepData, magnitude_data: List[Tuple[float, float]]) -> Optional[Path]:
+    def _save_matplotlib_image(self, sweep: SweepData, magnitude_data: List[Tuple[float, float]]) -> Path | None:
         """Save plot as image file using matplotlib."""
         try:
             filename = f"magnitude_sweep_{sweep.sweep_number:06d}.{self.image_format}"
diff --git a/vna_system/core/processing/results_storage.py b/vna_system/core/processing/results_storage.py
index aa125ef..a5636ff 100644
--- a/vna_system/core/processing/results_storage.py
+++ b/vna_system/core/processing/results_storage.py
@@ -4,7 +4,7 @@ import json
 import logging
 import threading
 from pathlib import Path
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List
 
 from vna_system.core.processing.base_processor import ProcessingResult
 
@@ -169,7 +169,7 @@ class ResultsStorage:
                 except Exception as e:
                     logger.error(f"Failed to remove sweep {sweep_number}: {e}")
 
-    def get_latest_results(self, processor_name: Optional[str] = None, limit: int = 10) -> List[ProcessingResult]:
+    def get_latest_results(self, processor_name: str | None = None, limit: int = 10) -> List[ProcessingResult]:
         """Get latest processing results."""
         with self._lock:
             results = []
@@ -186,7 +186,7 @@ class ResultsStorage:
 
             return results[:limit]
 
-    def get_result_by_sweep(self, sweep_number: int, processor_name: Optional[str] = None) -> List[ProcessingResult]:
+    def get_result_by_sweep(self, sweep_number: int, processor_name: str | None = None) -> List[ProcessingResult]:
         """Get processing results for specific sweep number."""
         with self._lock:
             results = []
@@ -227,7 +227,7 @@ class ResultsStorage:
 
             return results
 
-    def get_sweep_metadata(self, sweep_number: int) -> Optional[Dict[str, Any]]:
+    def get_sweep_metadata(self, sweep_number: int) -> Dict[str, Any] | None:
         """Get metadata for specific sweep."""
         with self._lock:
             if sweep_number not in self._cache:
@@ -243,7 +243,7 @@ class ResultsStorage:
 
             return None
 
-    def get_available_sweeps(self, limit: Optional[int] = None) -> List[int]:
+    def get_available_sweeps(self, limit: int | None = None) -> List[int]:
         """Get list of available sweep numbers."""
         with self._lock:
             sorted_sweeps = sorted(self._cache.keys(), reverse=True)
diff --git a/vna_system/core/processing/sweep_processor.py b/vna_system/core/processing/sweep_processor.py
index 026db98..03be78a 100644
--- a/vna_system/core/processing/sweep_processor.py
+++ b/vna_system/core/processing/sweep_processor.py
@@ -5,7 +5,7 @@ import logging
 import queue
 import threading
 import time
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List
 
 from vna_system.core.acquisition.sweep_buffer import SweepBuffer, SweepData
 from vna_system.core.processing.base_processor import BaseSweepProcessor, ProcessingResult
@@ -22,11 +22,11 @@ class SweepProcessingManager:
     def __init__(self, config_path: str = "vna_system/core/processing/config.json") -> None:
         self.processors: List[BaseSweepProcessor] = []
         self.config: Dict[str, Any] = {}
-        self.sweep_buffer: Optional[SweepBuffer] = None
+        self.sweep_buffer: SweepBuffer | None = None
 
         # Processing control
         self._running = False
-        self._thread: Optional[threading.Thread] = None
+        self._thread: threading.Thread | None = None
         self._stop_event = threading.Event()
         self._last_processed_sweep = 0
 
@@ -174,7 +174,7 @@ class SweepProcessingManager:
             except queue.Empty:
                 pass
 
-    def get_next_result(self, timeout: Optional[float] = None) -> Optional[ProcessingResult]:
+    def get_next_result(self, timeout: float | None = None) -> ProcessingResult | None:
         """Get next processing result from queue. Used by websocket handler."""
         try:
             return self.results_queue.get(timeout=timeout)
@@ -196,11 +196,11 @@ class SweepProcessingManager:
                 break
         return results
 
-    def get_latest_results(self, processor_name: Optional[str] = None, limit: int = 10) -> List[ProcessingResult]:
+    def get_latest_results(self, processor_name: str | None = None, limit: int = 10) -> List[ProcessingResult]:
         """Get latest processing results from storage, optionally filtered by processor name."""
         return self.results_storage.get_latest_results(processor_name, limit)
 
-    def get_result_by_sweep(self, sweep_number: int, processor_name: Optional[str] = None) -> List[ProcessingResult]:
+    def get_result_by_sweep(self, sweep_number: int, processor_name: str | None = None) -> List[ProcessingResult]:
         """Get processing results for a specific sweep number from storage."""
         return self.results_storage.get_result_by_sweep(sweep_number, processor_name)
 
diff --git a/vna_system/api/websockets/websocket_handler.py b/vna_system/core/processing/websocket_handler.py
similarity index 100%
rename from vna_system/api/websockets/websocket_handler.py
rename to vna_system/core/processing/websocket_handler.py
diff --git a/vna_system/core/settings/settings_manager.py b/vna_system/core/settings/settings_manager.py
new file mode 100644
index 0000000..261c290
--- /dev/null
+++ b/vna_system/core/settings/settings_manager.py
@@ -0,0 +1,352 @@
+from __future__ import annotations
+
+import json
+import logging
+import re
+from dataclasses import dataclass
+from datetime import datetime
+from enum import Enum
+from pathlib import Path
+from typing import Dict, List, Tuple
+
+from vna_system.config import config as cfg
+from vna_system.core.processing.results_storage import ResultsStorage
+
+logger = logging.getLogger(__name__)
+
+
+# ----------------------- Minimal enums & dataclass -----------------------
+
+class VNAMode(Enum):
+    S11 = "S11"
+    S21 = "S21"
+
+
+class CalibrationStandard(Enum):
+    OPEN = "open"
+    SHORT = "short"
+    LOAD = "load"
+    THROUGH = "through"
+
+
+@dataclass(frozen=True)
+class LogConfig:
+    """Parsed configuration from a selected config file."""
+    mode: VNAMode
+    file_path: Path
+    stem: str
+    start_hz: float | None
+    stop_hz: float | None
+    points: int | None
+    bw_hz: float | None
+
+
+# ----------------------- Filename parsing helpers --------------------------
+
+_UNIT_MULT = {
+    "hz": 1.0,
+    "khz": 1e3,
+    "mhz": 1e6,
+    "ghz": 1e9,
+}
+_PARAM_RE = re.compile(r"^(str|stp|pnts|bw)(?P<val>[0-9]+(?:\.[0-9]+)?)(?P<unit>[a-zA-Z]+)?$")
+
+
+def _to_hz(val: float, unit: str | None, default_hz: float) -> float:
+    if unit:
+        m = _UNIT_MULT.get(unit.lower())
+        if m:
+            return float(val) * m
+    return float(val) * default_hz
+
+
+def parse_config_filename(name: str, assume_mhz_for_freq: bool = True) -> Tuple[float | None, float | None, int | None, float] | None:
+    """
+    Parse tokens like: str100_stp8800_pnts1000_bw1khz.[bin]
+    - str/stp default to MHz if no unit (configurable)
+    - bw defaults to Hz if no unit
+    """
+    base = Path(name).stem
+    tokens = base.split("_")
+
+    start_hz = stop_hz = bw_hz = None
+    points: int | None = None
+
+    for t in tokens:
+        m = _PARAM_RE.match(t)
+        if not m:
+            continue
+        key = t[:3]
+        val = float(m.group("val"))
+        unit = m.group("unit")
+
+        if key == "str":
+            start_hz = _to_hz(val, unit, 1e6 if assume_mhz_for_freq else 1.0)
+        elif key == "stp":
+            stop_hz = _to_hz(val, unit, 1e6 if assume_mhz_for_freq else 1.0)
+        elif key == "pnt":  # token 'pnts'
+            points = int(val)
+        elif key == "bw":
+            bw_hz = _to_hz(val, unit, 1.0)
+
+    return start_hz, stop_hz, points, bw_hz
+
+
+# ----------------------- VNA Settings Manager ------------------------------
+
+class VNASettingsManager:
+    """
+    - Scans config_logs/{S11,S21}/ for available configs
+    - Controls current_log.bin symlink (must be a real symlink)
+    - Parses config params from filename
+    - Stores per-config calibration in:
+        calibration/<MODE>/<STEM>/<STANDARD>/<timestamp>_sweepNNNNNN/
+            - copies ALL processor result JSON files for that sweep (and metadata.json if present)
+    - UI helpers: select S11/S21, calibrate (through/open/short/load) by sweep number
+    """
+
+    def __init__(
+        self,
+        base_dir: Path | None = None,
+        config_logs_subdir: str = "binary_logs/config_logs",
+        current_log_name: str = "current_log.bin",
+        calibration_subdir: str = "calibration",
+        assume_mhz_for_freq: bool = True,
+        results_storage: ResultsStorage | None = None,
+    ):
+        self.base_dir = Path(base_dir or cfg.BASE_DIR)
+        self.cfg_logs_dir = self.base_dir / config_logs_subdir
+        self.current_log = self.cfg_logs_dir / current_log_name
+        self.calib_root = self.base_dir / calibration_subdir
+        self.assume_mhz_for_freq = assume_mhz_for_freq
+
+        # Ensure directory structure exists
+        (self.cfg_logs_dir / "S11").mkdir(parents=True, exist_ok=True)
+        (self.cfg_logs_dir / "S21").mkdir(parents=True, exist_ok=True)
+        self.calib_root.mkdir(parents=True, exist_ok=True)
+
+        # Results storage
+        self.results = results_storage or ResultsStorage(
+            storage_dir=str(self.base_dir / "processing_results")
+        )
+
+    # ---------- configuration selection & discovery ----------
+
+    def list_configs(self, mode: VNAMode | None = None) -> List[LogConfig]:
+        modes = [mode] if mode else [VNAMode.S11, VNAMode.S21]
+        out: List[LogConfig] = []
+        for m in modes:
+            d = self.cfg_logs_dir / m.value
+            if not d.exists():
+                continue
+            for fp in sorted(d.glob("*.bin")):
+                s, e, n, bw = parse_config_filename(fp.name, self.assume_mhz_for_freq)
+                out.append(LogConfig(
+                    mode=m,
+                    file_path=fp.resolve(),
+                    stem=fp.stem,
+                    start_hz=s,
+                    stop_hz=e,
+                    points=n,
+                    bw_hz=bw,
+                ))
+        return out
+
+    def set_current_config(self, mode: VNAMode, filename: str) -> LogConfig:
+        """
+        Update current_log.bin symlink to point to config_logs/<MODE>/<filename>.
+        Real symlink only; will raise if not supported.
+        """
+        target = (self.cfg_logs_dir / mode.value / filename).resolve()
+        if not target.exists():
+            raise FileNotFoundError(f"Config not found: {target}")
+
+        if self.current_log.exists() or self.current_log.is_symlink():
+            self.current_log.unlink()
+
+        # relative link if possible, else absolute (still a symlink)
+        try:
+            rel = target.relative_to(self.current_log.parent)
+        except ValueError:
+            rel = target
+
+        self.current_log.symlink_to(rel)
+        return self.get_current_config()
+
+    def get_current_config(self) -> LogConfig:
+        if not self.current_log.exists():
+            raise FileNotFoundError(f"{self.current_log} does not exist")
+
+        tgt = self.current_log.resolve()
+        mode = VNAMode(tgt.parent.name)  # expects .../config_logs/<MODE>/<file>
+        s, e, n, bw = parse_config_filename(tgt.name, self.assume_mhz_for_freq)
+        return LogConfig(
+            mode=mode,
+            file_path=tgt,
+            stem=tgt.stem,
+            start_hz=s, stop_hz=e, points=n, bw_hz=bw
+        )
+
+    # ---------- calibration capture (ALL processors) ----------
+
+    @staticmethod
+    def required_standards(mode: VNAMode) -> List[CalibrationStandard]:
+        return (
+            [CalibrationStandard.OPEN, CalibrationStandard.SHORT, CalibrationStandard.LOAD]
+            if mode == VNAMode.S11
+            else [CalibrationStandard.THROUGH]
+        )
+
+    def _calib_dir(self, cfg: LogConfig, standard: CalibrationStandard | None = None) -> Path:
+        base = self.calib_root / cfg.mode.value / cfg.stem
+        return base / standard.value if standard else base
+
+    def _calib_sweep_dir(self, cfg: LogConfig, standard: CalibrationStandard, sweep_number: int, ts: str | None = None) -> Path:
+        """
+        calibration/<MODE>/<STEM>/<STANDARD>/<timestamp>_sweepNNNNNN/
+        """
+        ts = ts or datetime.now().strftime("%Y%m%d_%H%M%S")
+        d = self._calib_dir(cfg, standard) / f"{ts}_sweep{sweep_number:06d}"
+        d.mkdir(parents=True, exist_ok=True)
+        return d
+
+    def record_calibration_from_sweep(
+        self,
+        standard: CalibrationStandard,
+        sweep_number: int,
+        *,
+        cfg: LogConfig | None = None
+    ) -> Path:
+        """
+        Capture ALL processor JSON results for the given sweep and save under:
+            calibration/<MODE>/<STEM>/<STANDARD>/<timestamp>_sweepNNNNNN/
+        Also copy metadata.json if available.
+        Returns the created sweep calibration directory.
+        """
+        cfg = cfg or self.get_current_config()
+
+        # Get ALL results for the sweep
+        results = self.results.get_result_by_sweep(sweep_number, processor_name=None)
+        if not results:
+            raise FileNotFoundError(f"No processor results found for sweep {sweep_number}")
+
+        # Determine destination dir
+        dst_dir = self._calib_sweep_dir(cfg, standard, sweep_number)
+
+        # Save processor files (re-serialize what ResultsStorage returns)
+        count = 0
+        for r in results:
+            try:
+                dst_file = dst_dir / f"{r.processor_name}.json"
+                payload = {
+                    "processor_name": r.processor_name,
+                    "sweep_number": r.sweep_number,
+                    "data": r.data,
+                }
+                # keep optional fields if present
+                if getattr(r, "plotly_figure", None) is not None:
+                    payload["plotly_figure"] = r.plotly_figure
+                if getattr(r, "file_path", None) is not None:
+                    payload["file_path"] = r.file_path
+
+                with open(dst_file, "w") as f:
+                    json.dump(payload, f, indent=2)
+                count += 1
+            except Exception as e:
+                logger.error(f"Failed to store processor '{r.processor_name}' for sweep {sweep_number}: {e}")
+
+        # Save metadata if available
+        try:
+            meta = self.results.get_sweep_metadata(sweep_number)
+            if meta:
+                with open(dst_dir / "metadata.json", "w") as f:
+                    json.dump(meta, f, indent=2)
+        except Exception as e:
+            logger.warning(f"Failed to write metadata for sweep {sweep_number}: {e}")
+
+        if count == 0:
+            raise RuntimeError(f"Nothing was written for sweep {sweep_number}")
+
+        logger.info(f"Stored calibration (standard={standard.value}) from sweep {sweep_number} into {dst_dir}")
+        return dst_dir
+
+    def latest_calibration(self, cfg: LogConfig | None = None) -> Dict[CalibrationStandard, Path] | None:
+        """
+        Returns the latest sweep directory per required standard for the current (or provided) config.
+        """
+        cfg = cfg or self.get_current_config()
+        out: Dict[CalibrationStandard, Path] | None = {}
+        for std in self.required_standards(cfg.mode):
+            d = self._calib_dir(cfg, std)
+            if not d.exists():
+                out[std] = None
+                continue
+            subdirs = sorted([p for p in d.iterdir() if p.is_dir()])
+            out[std] = subdirs[-1] if subdirs else None
+        return out
+
+    def calibration_status(self, cfg: LogConfig | None = None) -> Dict[str, bool]:
+        cfg = cfg or self.get_current_config()
+        latest = self.latest_calibration(cfg)
+        return {std.value: (p is not None and p.exists()) for std, p in latest.items()}
+
+    def is_fully_calibrated(self, cfg: LogConfig | None = None) -> bool:
+        return all(self.calibration_status(cfg).values())
+
+    # ---------- UI helpers ----------
+
+    def summary(self) -> Dict[str, object]:
+        cfg = self.get_current_config()
+        latest = self.latest_calibration(cfg)
+        return {
+            "mode": cfg.mode.value,
+            "current_log": str(self.current_log),
+            "selected_file": str(cfg.file_path),
+            "stem": cfg.stem,
+            "params": {
+                "start_hz": cfg.start_hz,
+                "stop_hz": cfg.stop_hz,
+                "points": cfg.points,
+                "bw_hz": cfg.bw_hz,
+            },
+            "required_standards": [s.value for s in self.required_standards(cfg.mode)],
+            "calibration_latest": {k.value: (str(v) if v else None) for k, v in latest.items()},
+            "is_fully_calibrated": self.is_fully_calibrated(cfg),
+        }
+
+    def ui_select_S11(self, filename: str) -> Dict[str, object]:
+        self.set_current_config(VNAMode.S11, filename)
+        return self.summary()
+
+    def ui_select_S21(self, filename: str) -> Dict[str, object]:
+        self.set_current_config(VNAMode.S21, filename)
+        return self.summary()
+
+    # Calibration triggers (buttons)
+    def ui_calibrate_through(self, sweep_number: int) -> Dict[str, object]:
+        cfg = self.get_current_config()
+        if cfg.mode != VNAMode.S21:
+            raise RuntimeError("THROUGH is only valid in S21 mode")
+        self.record_calibration_from_sweep(CalibrationStandard.THROUGH, sweep_number)
+        return self.summary()
+
+    def ui_calibrate_open(self, sweep_number: int) -> Dict[str, object]:
+        cfg = self.get_current_config()
+        if cfg.mode != VNAMode.S11:
+            raise RuntimeError("OPEN is only valid in S11 mode")
+        self.record_calibration_from_sweep(CalibrationStandard.OPEN, sweep_number)
+        return self.summary()
+
+    def ui_calibrate_short(self, sweep_number: int) -> Dict[str, object]:
+        cfg = self.get_current_config()
+        if cfg.mode != VNAMode.S11:
+            raise RuntimeError("SHORT is only valid in S11 mode")
+        self.record_calibration_from_sweep(CalibrationStandard.SHORT, sweep_number)
+        return self.summary()
+
+    def ui_calibrate_load(self, sweep_number: int) -> Dict[str, object]:
+        cfg = self.get_current_config()
+        if cfg.mode != VNAMode.S11:
+            raise RuntimeError("LOAD is only valid in S11 mode")
+        self.record_calibration_from_sweep(CalibrationStandard.LOAD, sweep_number)
+        return self.summary()
diff --git a/vna_system/core/singletons.py b/vna_system/core/singletons.py
index a5393e6..b0957f6 100644
--- a/vna_system/core/singletons.py
+++ b/vna_system/core/singletons.py
@@ -7,9 +7,11 @@ scattered throughout the codebase.
 """
 from vna_system.core.acquisition.data_acquisition import VNADataAcquisition
 from vna_system.core.processing.sweep_processor import SweepProcessingManager
-from vna_system.api.websockets.websocket_handler import WebSocketManager
+from vna_system.core.processing.websocket_handler import WebSocketManager
+from vna_system.core.settings.settings_manager import VNASettingsManager
 
 # Global singleton instances
 vna_data_acquisition_instance: VNADataAcquisition = VNADataAcquisition()
 processing_manager: SweepProcessingManager = SweepProcessingManager()
-websocket_manager: WebSocketManager = WebSocketManager(processing_manager)
\ No newline at end of file
+websocket_manager: WebSocketManager = WebSocketManager(processing_manager)
+settings_manager: VNASettingsManager = VNASettingsManager()
\ No newline at end of file
diff --git a/vna_system/scripts/__init__.py b/vna_system/scripts/__init__.py
deleted file mode 100644
index 55dbf87..0000000
--- a/vna_system/scripts/__init__.py
+++ /dev/null
@@ -1 +0,0 @@
-"""VNA System scripts module."""
\ No newline at end of file