Merge pull request 'Merge v1.4.1 from dev' (#2) from dev into main

## [1.4.1] - 2026-03-17

### Fixed
- `config.ini` now saves to `AppData\Local\Series3Watcher\` instead of `Program Files` — fixes permission denied error on first-run wizard save.
- Config path resolution in both `series3_tray.py` and `series3_watcher.py` updated to use `sys.frozen` + `LOCALAPPDATA` when running as a PyInstaller `.exe`.
- Status menu item now uses a callable so it updates every time the menu opens — was showing stale "Starting..." while tooltip correctly showed current status.
- Settings dialog now opens in its own thread — fixes unresponsive tabs and text fields while the watcher loop is running.
- Tray icon reverted to plain colored dot — custom icon graphic was unreadable at 16px tray size. `.ico` file is still used for the `.exe` file icon.

### Changed
- Terra-View URL field in settings wizard now accepts base URL only (e.g. `http://192.168.x.x:8000`) — `/api/series3/heartbeat` endpoint appended automatically.
- Test Connection button now hits `/health` endpoint instead of posting a fake heartbeat — no database side effects.
- "terra-view URL" label capitalized to "Terra-View URL".
- Default log path updated to `AppData\Local\Series3Watcher\agent_logs\series3_watcher.log`.
- Installer now creates `agent_logs\` folder on install.
- `BUILDING.md` added — step-by-step guide for building, releasing, and updating.

## [1.4.0] - 2026-03-12

### Added
- `series3_tray.py` — system tray launcher using `pystray` + `Pillow`. Color-coded icon (green=OK, amber=Pending, red=Missing, purple=Error, grey=Starting). Right-click menu shows live status, unit count, last scan age, Open Log Folder, and Exit.
- `run_watcher(state, stop_event)` in `series3_watcher.py` for background thread use by the tray. Shared `state` dict updated on every scan cycle with status, unit list, last scan time, and last error.
- Interruptible sleep in watcher loop — tray exit is immediate, no waiting out the full scan interval.

### Changed
- `main()` now calls `run_watcher()` — standalone behavior unchanged.
- `requirements.txt` updated to document tray dependencies (`pystray`, `Pillow`); watcher itself remains stdlib-only.

.gitignore

@@ -22,7 +22,9 @@ env/
 # Distribution / packaging
 build/
 dist/
+Output/
 *.egg-info/
+*.spec
 
 # -------------------------
 # Logs + runtime artifacts

BUILDING.md

@@ -0,0 +1,117 @@
+# Building & Releasing Series 3 Watcher
+
+## Prerequisites (Win7 VM — do this once)
+
+- Python 3.7.2 (or 3.8.10 if SP1 is installed)
+- Inno Setup 6 — installed at `C:\Program Files (x86)\Inno Setup 6\`
+- PyInstaller, pystray, Pillow — installed automatically by `build.bat`
+
+The Win7 VM is the build machine. All builds must happen there to ensure
+compatibility with the production DL2 computer.
+
+---
+
+## First-Time Install on a New Machine
+
+Do this when setting up a brand new machine that has never had the watcher before.
+
+**Step 1 — Build the .exe (on the Win7 VM)**
+
+1. Copy the `series3-watcher/` folder to the VM (shared folder, USB, etc.)
+2. Double-click `build.bat`
+3. Wait for it to finish — output: `dist\series3-watcher.exe`
+
+**Step 2 — Build the installer (on the Win7 VM)**
+
+1. Open `installer.iss` in Inno Setup Compiler
+2. Click **Build → Compile**
+3. Output: `Output\series3-watcher-setup.exe`
+
+**Step 3 — Create a Gitea release**
+
+1. On your main machine, go to `https://gitea.serversdown.net/serversdown/series3-watcher`
+2. Click **Releases → New Release**
+3. Set the tag to match the version in `series3_watcher.py` (e.g. `v1.4.1`)
+4. Upload **both** files as release assets:
+   - `dist\series3-watcher.exe` — used by the auto-updater on existing installs
+   - `Output\series3-watcher-setup.exe` — used for fresh installs
+
+**Step 4 — Install on the target machine**
+
+1. Download `series3-watcher-setup.exe` from the Gitea release
+2. Run it on the target machine — installs to `C:\Program Files\Series3Watcher\`
+3. The watcher launches automatically after install (or on next login)
+4. The Setup Wizard appears on first run — fill in the Terra-View URL and Blastware path
+
+---
+
+## Releasing an Update (existing machines auto-update)
+
+Do this for any code change — bug fix, new feature, etc.
+
+**Step 1 — Bump the version**
+
+In `series3_watcher.py`, update the `VERSION` string:
+```python
+VERSION = "1.4.2"   # increment appropriately
+```
+Also update `installer.iss`:
+```
+AppVersion=1.4.2
+```
+
+**Step 2 — Build the .exe (on the Win7 VM)**
+
+1. Pull the latest code to the VM
+2. Double-click `build.bat`
+3. Output: `dist\series3-watcher.exe`
+
+> For hotfixes you can skip Inno Setup — existing machines only need the `.exe`.
+> Only rebuild the installer if you need a fresh install package for a new machine.
+
+**Step 3 — Create a Gitea release**
+
+1. Go to `https://gitea.serversdown.net/serversdown/series3-watcher`
+2. Click **Releases → New Release**
+3. Tag must match the new version exactly (e.g. `v1.4.2`) — the auto-updater
+   compares this tag against its own version to decide whether to update
+4. Upload `dist\series3-watcher.exe` as a release asset
+5. Optionally upload `Output\series3-watcher-setup.exe` if you rebuilt the installer
+
+**Step 4 — Done**
+
+Existing installs check Gitea every ~5 minutes. When they see the new tag they
+will download `series3-watcher.exe`, swap it in place, and relaunch silently.
+No user action required on the target machine.
+
+---
+
+## Version Numbering
+
+Follows Semantic Versioning: `MAJOR.MINOR.PATCH`
+
+| Change type | Example |
+|-------------|---------|
+| Bug fix / text change | `1.4.1 → 1.4.2` |
+| New feature | `1.4.x → 1.5.0` |
+| Breaking change | `1.x.x → 2.0.0` |
+
+---
+
+## Files That Go in the Gitea Release
+
+| File | Required for | Notes |
+|------|-------------|-------|
+| `dist\series3-watcher.exe` | Auto-updates on existing machines | Always upload this |
+| `Output\series3-watcher-setup.exe` | Fresh installs on new machines | Only needed for new deployments |
+
+---
+
+## Files That Are NOT Committed to Git
+
+- `dist/` — PyInstaller output
+- `Output/` — Inno Setup output
+- `build/` — PyInstaller temp files
+- `*.spec` — PyInstaller spec file
+- `config.ini` — machine-specific, never commit
+- `agent_logs/` — log files

CHANGELOG.md

@@ -6,6 +6,23 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ---
 
+## [1.4.1] - 2026-03-17
+
+### Fixed
+- `config.ini` now saves to `AppData\Local\Series3Watcher\` instead of `Program Files` — fixes permission denied error on first-run wizard save.
+- Config path resolution in both `series3_tray.py` and `series3_watcher.py` updated to use `sys.frozen` + `LOCALAPPDATA` when running as a PyInstaller `.exe`.
+- Status menu item now uses a callable so it updates every time the menu opens — was showing stale "Starting..." while tooltip correctly showed current status.
+- Settings dialog now opens in its own thread — fixes unresponsive tabs and text fields while the watcher loop is running.
+- Tray icon reverted to plain colored dot — custom icon graphic was unreadable at 16px tray size. `.ico` file is still used for the `.exe` file icon.
+
+### Changed
+- Terra-View URL field in settings wizard now accepts base URL only (e.g. `http://192.168.x.x:8000`) — `/api/series3/heartbeat` endpoint appended automatically.
+- Test Connection button now hits `/health` endpoint instead of posting a fake heartbeat — no database side effects.
+- "terra-view URL" label capitalized to "Terra-View URL".
+- Default log path updated to `AppData\Local\Series3Watcher\agent_logs\series3_watcher.log`.
+- Installer now creates `agent_logs\` folder on install.
+- `BUILDING.md` added — step-by-step guide for building, releasing, and updating.
+
 ## [1.4.0] - 2026-03-12
 
 ### Added

README.md

@@ -1,4 +1,4 @@
-# Series 3 Watcher v1.4
+# Series 3 Watcher v1.4.1
 
 Monitors Instantel **Series 3 (Minimate)** call-in activity on a Blastware server. Runs as a **system tray app** that starts automatically on login, reports heartbeats to terra-view, and self-updates from Gitea.
 
@@ -23,21 +23,12 @@ Updates can also be pushed remotely from terra-view → **Settings → Developer
 
 ---
 
-## Building from Source
+## Building & Releasing
 
-Prerequisites (on a **Python 3.8** machine — required for Win7 compatibility):
+See [BUILDING.md](BUILDING.md) for the full step-by-step process covering:
-
+- First-time build and installer creation
-```
+- Publishing a release to Gitea
-pip install pystray Pillow pyinstaller
+- Releasing hotfix updates (auto-updater picks them up automatically)
-```
-
-Then run:
-
-```
-build.bat
-```
-
-This produces `dist\series3-watcher.exe`. To build the installer, open `installer.iss` in [Inno Setup](https://jrsoftware.org/isinfo.php) and click Build.
 
 ---
 
@@ -62,7 +53,7 @@ All settings live in `config.ini`. The Setup Wizard covers every field, but here
 | Key | Description |
 |-----|-------------|
 | `API_ENABLED` | `true` to send heartbeats to terra-view |
-| `API_URL` | terra-view heartbeat endpoint, e.g. `http://192.168.1.10:8000/api/series3/heartbeat` |
+| `API_URL` | Terra-View base URL, e.g. `http://192.168.1.10:8000` — the `/api/series3/heartbeat` endpoint is appended automatically |
 | `API_INTERVAL_SECONDS` | How often to POST (default `300`) |
 | `SOURCE_ID` | Identifier for this machine (defaults to hostname) |
 | `SOURCE_TYPE` | Always `series3_watcher` |
@@ -126,7 +117,7 @@ To view connected watchers: **Settings → Developer → Watcher Manager**.
 
 ## Versioning
 
-Follows **Semantic Versioning**. Current release: **v1.4.0**.
+Follows **Semantic Versioning**. Current release: **v1.4.1**.
 See `CHANGELOG.md` for full history.
 
 ---

README_DL2.md

@@ -1,26 +0,0 @@
-# Series 3 Watcher — v1_0(py38-safe) for DL2
-
-**Target**: Windows 7 + Python 3.8.10  
-**Baseline**: v5_4 (no logic changes)
-
-## Files
-- series3_agent_v1_0_py38.py — main script (py38-safe)
-- config.ini — your config (already included)
-- series3_roster.csv — your roster (already included, this auto updates from a URL to a dropbox file)
-- requirements.txt — none beyond stdlib
-
-## Install
-1) Create `C:\SeismoEmitter\` on DL2
-2) Extract this ZIP into that folder
-3) Open CMD:
-   ```cmd
-   cd C:\SeismoEmitter
-   python series3_agent_v1_0_py38.py
-   ```
-(If the console shows escape codes on Win7, set `COLORIZE = False` in `config.ini`.)
-
-## Quick validation
-- Heartbeat prints Local/UTC timestamps
-- One line per active roster unit with OK/Pending/Missing, Age, Last, File
-- Unexpected units block shows .MLG not in roster
-- agent.log rotates per LOG_RETENTION_DAYS

build.bat

@@ -3,9 +3,13 @@ echo Building series3-watcher.exe...
 pip install pyinstaller pystray Pillow
 
 REM Check whether icon.ico exists alongside this script.
-REM If it does, include it; otherwise build without a custom icon.
+REM If it does, embed it as the .exe icon AND bundle it as a data file
+REM so the tray overlay can load it at runtime.
 if exist "%~dp0icon.ico" (
-    pyinstaller --onefile --windowed --name series3-watcher --icon="%~dp0icon.ico" series3_tray.py
+    pyinstaller --onefile --windowed --name series3-watcher ^
+        --icon="%~dp0icon.ico" ^
+        --add-data "%~dp0icon.ico;." ^
+        series3_tray.py
 ) else (
     echo [INFO] icon.ico not found -- building without custom icon.
     pyinstaller --onefile --windowed --name series3-watcher series3_tray.py

config-template.ini

@@ -19,7 +19,7 @@ MISSING_HOURS = 24
 
 # Logging
 ENABLE_LOGGING     = True
-LOG_FILE           = C:\SeismoEmitter\agent_logs\series3_watcher.log
+LOG_FILE           = C:\Users\%USERNAME%\AppData\Local\Series3Watcher\agent_logs\series3_watcher.log
 LOG_RETENTION_DAYS = 30
 
 # Console colors - (Doesn't work on windows 7)

installer.iss

@@ -3,7 +3,7 @@
 
 [Setup]
 AppName=Series 3 Watcher
-AppVersion=1.4.0
+AppVersion=1.4.1
 AppPublisher=Terra-Mechanics Inc.
 DefaultDirName={pf}\Series3Watcher
 DefaultGroupName=Series 3 Watcher
@@ -16,6 +16,10 @@ PrivilegesRequired=admin
 [Tasks]
 Name: "desktopicon"; Description: "Create a &desktop icon"; GroupDescription: "Additional icons:"; Flags: unchecked
 
+[Dirs]
+; Create the agent_logs folder so the watcher can write logs on first run
+Name: "{app}\agent_logs"
+
 [Files]
 ; Main executable — built by build.bat / PyInstaller
 Source: "dist\series3-watcher.exe"; DestDir: "{app}"; Flags: ignoreversion

series3_tray.py

@@ -1,5 +1,5 @@
 """
-Series 3 Watcher — System Tray Launcher  v1.4.0
+Series 3 Watcher — System Tray Launcher  v1.4.1
 Requires: pystray, Pillow, tkinter (stdlib)
 
 Run with:  pythonw series3_tray.py   (no console window)
@@ -126,8 +126,21 @@ def apply_update(download_url):
 
 # --------------- Paths ---------------
 
-HERE = os.path.dirname(os.path.abspath(__file__))
+# Executable location — used for bundled assets (icon.ico etc.)
-CONFIG_PATH = os.path.join(HERE, "config.ini")
+if getattr(sys, "frozen", False):
+    HERE = os.path.dirname(os.path.abspath(sys.executable))
+else:
+    HERE = os.path.dirname(os.path.abspath(__file__))
+
+# config.ini lives in AppData so normal users can write it without UAC issues.
+# Fall back to the exe directory when running from source (dev mode).
+if getattr(sys, "frozen", False):
+    _appdata = os.environ.get("LOCALAPPDATA") or os.environ.get("APPDATA") or HERE
+    CONFIG_DIR = os.path.join(_appdata, "Series3Watcher")
+    os.makedirs(CONFIG_DIR, exist_ok=True)
+else:
+    CONFIG_DIR = HERE
+CONFIG_PATH = os.path.join(CONFIG_DIR, "config.ini")
 
 
 # --------------- Icon drawing ---------------
@@ -144,7 +157,7 @@ ICON_SIZE = 64
 
 
 def make_icon(status):
-    """Draw a solid filled circle on a transparent background."""
+    """Draw a plain colored circle for the system tray — clean and readable at 16px."""
     color = COLORS.get(status, COLORS["starting"])
     img = Image.new("RGBA", (ICON_SIZE, ICON_SIZE), (0, 0, 0, 0))
     draw = ImageDraw.Draw(img)
@@ -233,15 +246,13 @@ class WatcherTray:
     # --- Menu item callbacks ---
 
     def _open_settings(self, icon, item):
-        """Open the settings dialog. On save, restart watcher thread."""
+        """Open the settings dialog in its own thread so the tray stays responsive."""
-        from settings_dialog import show_dialog
+        def _run():
-        saved = show_dialog(CONFIG_PATH, wizard=False)
+            from settings_dialog import show_dialog
-        if saved:
+            saved = show_dialog(CONFIG_PATH, wizard=False)
-            self._restart_watcher()
+            if saved:
-            # Rebuild menu so status label refreshes
+                self._restart_watcher()
-            if self._icon is not None:
+        threading.Thread(target=_run, daemon=True, name="settings-dialog").start()
-                with self._menu_lock:
-                    self._icon.menu = self._build_menu()
 
     def _open_logs(self, icon, item):
         log_dir = self.state.get("log_dir")
@@ -299,17 +310,12 @@ class WatcherTray:
         return pystray.Menu(*items)
 
     def _build_menu(self):
-        # Capture current text/submenu at build time; pystray will call
+        # Use a callable for the status item so pystray re-evaluates it
-        # callables each render, but static strings are fine for infrequent
+        # every time the menu is opened — keeps it in sync with the tooltip.
-        # menu rebuilds. We use callables for the dynamic items so that the
-        # text shown on hover/open is current.
-        status_text = self._status_text()
-        units_submenu = self._build_units_submenu()
-
         return pystray.Menu(
-            pystray.MenuItem(status_text, None, enabled=False),
+            pystray.MenuItem(lambda item: self._status_text(), None, enabled=False),
             pystray.Menu.SEPARATOR,
-            pystray.MenuItem("Units", units_submenu),
+            pystray.MenuItem("Units", lambda item: self._build_units_submenu()),
             pystray.Menu.SEPARATOR,
             pystray.MenuItem("Settings...", self._open_settings),
             pystray.MenuItem("Open Log Folder", self._open_logs),

series3_watcher.py

@@ -1,5 +1,5 @@
 """
-Series 3 Watcher — v1.4.0
+Series 3 Watcher — v1.4.1
 
 Environment:
 - Python 3.8 (Windows 7 compatible)
@@ -17,6 +17,7 @@ Key Features:
 
 import os
 import re
+import sys
 import time
 import json
 import threading
@@ -62,7 +63,10 @@ def load_config(path: str) -> Dict[str, Any]:
         "OK_HOURS": float(get_int("OK_HOURS", 12)),
         "MISSING_HOURS": float(get_int("MISSING_HOURS", 24)),
         "ENABLE_LOGGING": get_bool("ENABLE_LOGGING", True),
-        "LOG_FILE": get_str("LOG_FILE", r"C:\SeismoEmitter\agent_logs\series3_watcher.log"),
+        "LOG_FILE": get_str("LOG_FILE", os.path.join(
+            os.environ.get("LOCALAPPDATA") or os.environ.get("APPDATA") or "C:\\",
+            "Series3Watcher", "agent_logs", "series3_watcher.log"
+        )),
         "LOG_RETENTION_DAYS": get_int("LOG_RETENTION_DAYS", 30),
         "COLORIZE": get_bool("COLORIZE", False),  # Win7 default off
         "MLG_HEADER_BYTES": max(256, min(get_int("MLG_HEADER_BYTES", 2048), 65536)),
@@ -216,7 +220,19 @@ def scan_latest(
 
 
 # --- API heartbeat / SFM telemetry helpers ---
-VERSION = "1.4.0"
+VERSION = "1.4.1"
+
+
+def _read_log_tail(log_file: str, n: int = 25) -> Optional[list]:
+    """Return the last n lines of the log file as a list of strings, or None on failure."""
+    if not log_file:
+        return None
+    try:
+        with open(log_file, "r", errors="replace") as f:
+            lines = f.readlines()
+        return [l.rstrip("\n") for l in lines[-n:]]
+    except Exception:
+        return None
 
 
 def send_api_payload(payload: dict, api_url: str) -> Optional[dict]:
@@ -301,8 +317,14 @@ def run_watcher(state: Dict[str, Any], stop_event: threading.Event) -> None:
       state["log_dir"]       — directory containing the log file
       state["cfg"]           — loaded config dict
     """
-    here = os.path.dirname(__file__) or "."
+    if getattr(sys, "frozen", False):
-    config_path = os.path.join(here, "config.ini")
+        here = os.path.dirname(os.path.abspath(sys.executable))
+        _appdata = os.environ.get("LOCALAPPDATA") or os.environ.get("APPDATA") or here
+        config_dir = os.path.join(_appdata, "Series3Watcher")
+    else:
+        here = os.path.dirname(os.path.abspath(__file__)) or "."
+        config_dir = here
+    config_path = os.path.join(config_dir, "config.ini")
 
     state["status"] = "starting"
     state["units"] = []
@@ -441,6 +463,7 @@ def run_watcher(state: Dict[str, Any], stop_event: threading.Event) -> None:
                 if now_ts - last_api_ts >= interval:
                     hb_payload = build_sfm_payload(latest, cfg)
                     hb_payload["version"] = VERSION
+                    hb_payload["log_tail"] = _read_log_tail(cfg.get("LOG_FILE", ""), 25)
                     response = send_api_payload(hb_payload, cfg.get("API_URL", ""))
                     last_api_ts = now_ts
                     # Surface update signal to tray

settings_dialog.py

@@ -34,7 +34,10 @@ DEFAULTS = {
     "MISSING_HOURS":        "24",
     "MLG_HEADER_BYTES":     "2048",
     "ENABLE_LOGGING":       "true",
-    "LOG_FILE":             r"C:\SeismoEmitter\agent_logs\series3_watcher.log",
+    "LOG_FILE":             os.path.join(
+                                os.environ.get("LOCALAPPDATA") or os.environ.get("APPDATA") or "C:\\",
+                                "Series3Watcher", "agent_logs", "series3_watcher.log"
+                            ),
     "LOG_RETENTION_DAYS":   "30",
     "COLORIZE":             "false",
 }
@@ -206,7 +209,12 @@ class SettingsDialog:
 
         # Connection
         self.var_api_enabled        = tk.BooleanVar(value=v["API_ENABLED"].lower() in ("1","true","yes","on"))
-        self.var_api_url            = tk.StringVar(value=v["API_URL"])
+        # Strip the fixed endpoint suffix so the dialog shows just the base URL
+        _raw_url = v["API_URL"]
+        _suffix = "/api/series3/heartbeat"
+        if _raw_url.endswith(_suffix):
+            _raw_url = _raw_url[:-len(_suffix)]
+        self.var_api_url            = tk.StringVar(value=_raw_url)
         self.var_api_interval       = tk.StringVar(value=v["API_INTERVAL_SECONDS"])
         self.var_source_id          = tk.StringVar(value=v["SOURCE_ID"])
         self.var_source_type        = tk.StringVar(value=v["SOURCE_TYPE"])
@@ -277,10 +285,40 @@ class SettingsDialog:
 
         _add_label_check(f, 0, "API Enabled", self.var_api_enabled)
 
-        _add_label_entry(
+        # URL row — entry + Test button in an inner frame
-            f, 1, "terra-view URL", self.var_api_url,
+        tk.Label(f, text="Terra-View URL", anchor="w").grid(
-            hint="http://192.168.x.x:8000/api/heartbeat",
+            row=1, column=0, sticky="w", padx=(8, 4), pady=4
         )
+        url_frame = tk.Frame(f)
+        url_frame.grid(row=1, column=1, sticky="ew", padx=(0, 8), pady=4)
+        url_frame.columnconfigure(0, weight=1)
+
+        url_entry = ttk.Entry(url_frame, textvariable=self.var_api_url, width=32)
+        url_entry.grid(row=0, column=0, sticky="ew")
+
+        # Placeholder hint behaviour
+        _hint = "http://192.168.x.x:8000"
+        if not self.var_api_url.get():
+            url_entry.config(foreground="grey")
+            url_entry.insert(0, _hint)
+            def _on_focus_in(e):
+                if url_entry.get() == _hint:
+                    url_entry.delete(0, tk.END)
+                    url_entry.config(foreground="black")
+            def _on_focus_out(e):
+                if not url_entry.get():
+                    url_entry.config(foreground="grey")
+                    url_entry.insert(0, _hint)
+                    self.var_api_url.set("")
+            url_entry.bind("<FocusIn>", _on_focus_in)
+            url_entry.bind("<FocusOut>", _on_focus_out)
+
+        self._test_btn = ttk.Button(url_frame, text="Test", width=6,
+                                    command=self._test_connection)
+        self._test_btn.grid(row=0, column=1, padx=(4, 0))
+
+        self._test_status = tk.Label(url_frame, text="", anchor="w", width=20)
+        self._test_status.grid(row=0, column=2, padx=(6, 0))
 
         _add_label_spinbox(f, 2, "API Interval (sec)", self.var_api_interval, 30, 3600)
 
@@ -289,6 +327,40 @@ class SettingsDialog:
 
         _add_label_entry(f, 4, "Source Type", self.var_source_type, readonly=True)
 
+    def _test_connection(self):
+        """POST a minimal ping to the Terra-View heartbeat endpoint and show result."""
+        import urllib.request
+        import urllib.error
+
+        self._test_status.config(text="Testing...", foreground="grey")
+        self._test_btn.config(state="disabled")
+        self.root.update_idletasks()
+
+        raw = self.var_api_url.get().strip()
+        if not raw or raw == "http://192.168.x.x:8000":
+            self._test_status.config(text="Enter a URL first", foreground="orange")
+            self._test_btn.config(state="normal")
+            return
+
+        url = raw.rstrip("/") + "/health"
+
+        try:
+            req = urllib.request.Request(url)
+            with urllib.request.urlopen(req, timeout=5) as resp:
+                if resp.status == 200:
+                    self._test_status.config(text="Connected!", foreground="green")
+                else:
+                    self._test_status.config(
+                        text="HTTP {}".format(resp.status), foreground="orange"
+                    )
+        except urllib.error.URLError as e:
+            reason = str(e.reason) if hasattr(e, "reason") else str(e)
+            self._test_status.config(text="Failed: {}".format(reason[:30]), foreground="red")
+        except Exception as e:
+            self._test_status.config(text="Error: {}".format(str(e)[:30]), foreground="red")
+        finally:
+            self._test_btn.config(state="normal")
+
     def _build_tab_paths(self, nb):
         f = self._tab_frame(nb, "Paths")
 
@@ -376,13 +448,12 @@ class SettingsDialog:
         if source_id.startswith("Defaults to hostname"):
             source_id = ""
 
-        # Resolve api_url placeholder
+        # Resolve api_url — append the fixed endpoint, strip placeholder
         api_url = self.var_api_url.get().strip()
-        if api_url.startswith("http://192.168"):
+        if api_url == "http://192.168.x.x:8000" or not api_url:
-            # This is the hint — only keep it if it looks like a real URL
-            pass  # leave as-is; user may have typed it intentionally
-        if api_url == "http://192.168.x.x:8000/api/heartbeat":
             api_url = ""
+        else:
+            api_url = api_url.rstrip("/") + "/api/series3/heartbeat"
 
         values = {
             "API_ENABLED":          "true" if self.var_api_enabled.get() else "false",