diff --git a/src/ars_wireworks/ui/main_window.py b/src/ars_wireworks/ui/main_window.py
index efb5de4..8faba7a 100644
--- a/src/ars_wireworks/ui/main_window.py
+++ b/src/ars_wireworks/ui/main_window.py
@@ -149,6 +149,13 @@
     {"dipole", "inverted_v", "ocfd", "random_wire", "vertical"}
 )
 
+#: Shown in the Sweep tab in Basic Mode, where the sweep controls are hidden —
+#: the frequency sweep is an Advanced-Mode feature (spec §8).
+_SWEEP_BASIC_PROMPT = (
+    "The frequency sweep is an Advanced-Mode feature.\n"
+    "Use View → Promote to Advanced Mode to run one."
+)
+
 #: QSettings key for the persisted window geometry (spec §10).
 _GEOMETRY_KEY = "window/geometry"
 
@@ -539,6 +546,8 @@ def _promote_to_advanced(self) -> None:
         self._advanced_radials_box.setVisible(True)
         self._advanced_yagi_box.setVisible(True)
         self._advanced_path_box.setVisible(True)
+        # The sweep controls are now available — drop the Basic-Mode hint.
+        self._sweep_view.clear()
         centre = self._frequency.value()
         self._sweep_start.setValue(centre * 0.95)
         self._sweep_stop.setValue(centre * 1.05)
@@ -1435,6 +1444,10 @@ def _build_central_widget(self) -> QWidget:
         self._buildsheet_view = BuildSheetView()
         self._path_view = PathView()
         self._sweep_view = SweepView()
+        if not self._advanced:
+            # The sweep controls are Advanced-only, so point Basic-Mode users
+            # to them instead of an empty "run a sweep" prompt with no button.
+            self._sweep_view.clear(_SWEEP_BASIC_PROMPT)
         results_tabs = QTabWidget()
         results_tabs.addTab(self._output, "Summary")
         results_tabs.addTab(self._pattern_view, "Radiation pattern")
@@ -1772,6 +1785,8 @@ def _silently_promote_to_advanced(self) -> None:
         self._advanced_radials_box.setVisible(True)
         self._advanced_yagi_box.setVisible(True)
         self._advanced_path_box.setVisible(True)
+        # The sweep controls are now available — drop the Basic-Mode hint.
+        self._sweep_view.clear()
 
     def _reset_loaded_components(
         self,
diff --git a/src/ars_wireworks/ui/sweep_view.py b/src/ars_wireworks/ui/sweep_view.py
index 37a784a..2fe5757 100644
--- a/src/ars_wireworks/ui/sweep_view.py
+++ b/src/ars_wireworks/ui/sweep_view.py
@@ -34,7 +34,7 @@ def show_sweep(self, sweep: SweepResults) -> None:
         draw_sweep_plot(self._figure, sweep)
         self._canvas.draw_idle()
 
-    def clear(self) -> None:
-        """Show the placeholder — no sweep has run yet."""
-        draw_placeholder(self._figure, _PROMPT)
+    def clear(self, message: str = _PROMPT) -> None:
+        """Show a placeholder message — the pre-run (or unavailable) state."""
+        draw_placeholder(self._figure, message)
         self._canvas.draw_idle()
diff --git a/tests/test_sweep.py b/tests/test_sweep.py
index 134f048..64fa764 100644
--- a/tests/test_sweep.py
+++ b/tests/test_sweep.py
@@ -47,3 +47,27 @@ def test_main_window_runs_a_sweep(qapp) -> None:
     window._sweep_steps.setValue(3)
     window._on_run_sweep()
     assert window._sweep_view._figure.axes[0].lines
+
+
+def _placeholder_text(window) -> str:
+    texts = window._sweep_view._figure.axes[0].texts
+    return texts[0].get_text() if texts else ""
+
+
+def test_basic_mode_sweep_tab_points_to_advanced(qapp) -> None:
+    from ars_wireworks.ui.main_window import MainWindow
+
+    window = MainWindow()
+    # Basic Mode by default: the Sweep tab explains the controls are Advanced.
+    assert not window._advanced
+    assert "Advanced Mode" in _placeholder_text(window)
+
+
+def test_promoting_drops_the_basic_sweep_hint(qapp) -> None:
+    from ars_wireworks.ui.main_window import MainWindow
+
+    window = MainWindow()
+    window._silently_promote_to_advanced()
+    # After promotion the hint is gone — the ready-to-run prompt shows instead.
+    assert "Advanced Mode" not in _placeholder_text(window)
+    assert "sweep" in _placeholder_text(window).lower()