diff --git a/routes/listening_post.py b/routes/listening_post.py
index ac7b0cb..19725a2 100644
--- a/routes/listening_post.py
+++ b/routes/listening_post.py
@@ -168,14 +168,16 @@ def scanner_loop():
             scanner_current_freq = current_freq
 
             # Notify clients of frequency change
-            try:
-                scanner_queue.put_nowait({
-                    'type': 'freq_change',
-                    'frequency': current_freq,
-                    'scanning': not signal_detected
-                })
-            except queue.Full:
-                pass
+            try:
+                scanner_queue.put_nowait({
+                    'type': 'freq_change',
+                    'frequency': current_freq,
+                    'scanning': not signal_detected,
+                    'range_start': scanner_config['start_freq'],
+                    'range_end': scanner_config['end_freq']
+                })
+            except queue.Full:
+                pass
 
             # Start rtl_fm at this frequency
             freq_hz = int(current_freq * 1e6)
@@ -259,16 +261,18 @@ def scanner_loop():
                     audio_detected = rms > effective_threshold
 
                 # Send level info to clients
-                try:
-                    scanner_queue.put_nowait({
-                        'type': 'scan_update',
-                        'frequency': current_freq,
-                        'level': int(rms),
+                try:
+                    scanner_queue.put_nowait({
+                        'type': 'scan_update',
+                        'frequency': current_freq,
+                        'level': int(rms),
                         'threshold': int(effective_threshold) if 'effective_threshold' in dir() else 0,
-                        'detected': audio_detected
+                        'detected': audio_detected,
+                        'range_start': scanner_config['start_freq'],
+                        'range_end': scanner_config['end_freq']
                     })
-                except queue.Full:
-                    pass
+                except queue.Full:
+                    pass
 
                 if audio_detected and scanner_running:
                     if not signal_detected:
@@ -282,17 +286,19 @@ def scanner_loop():
                         # Start audio streaming for user
                         _start_audio_stream(current_freq, mod)
 
-                        try:
-                            scanner_queue.put_nowait({
-                                'type': 'signal_found',
-                                'frequency': current_freq,
-                                'modulation': mod,
-                                'audio_streaming': True,
-                                'level': int(rms),
-                                'threshold': int(effective_threshold)
-                            })
-                        except queue.Full:
-                            pass
+                    try:
+                        scanner_queue.put_nowait({
+                            'type': 'signal_found',
+                            'frequency': current_freq,
+                            'modulation': mod,
+                            'audio_streaming': True,
+                            'level': int(rms),
+                            'threshold': int(effective_threshold),
+                            'range_start': scanner_config['start_freq'],
+                            'range_end': scanner_config['end_freq']
+                        })
+                    except queue.Full:
+                        pass
 
                     # Check for skip signal
                     if scanner_skip_signal:
@@ -328,7 +334,9 @@ def scanner_loop():
                         try:
                             scanner_queue.put_nowait({
                                 'type': 'signal_lost',
-                                'frequency': current_freq
+                                'frequency': current_freq,
+                                'range_start': scanner_config['start_freq'],
+                                'range_end': scanner_config['end_freq']
                             })
                         except queue.Full:
                             pass
@@ -446,7 +454,9 @@ def scanner_loop_power():
                         'frequency': end_mhz,
                         'level': 0,
                         'threshold': int(float(scanner_config.get('snr_threshold', 12)) * 100),
-                        'detected': False
+                        'detected': False,
+                        'range_start': scanner_config['start_freq'],
+                        'range_end': scanner_config['end_freq']
                     })
                 except queue.Full:
                     pass
@@ -503,7 +513,9 @@ def scanner_loop_power():
                         'frequency': end_mhz,
                         'level': 0,
                         'threshold': int(float(scanner_config.get('snr_threshold', 12)) * 100),
-                        'detected': False
+                        'detected': False,
+                        'range_start': scanner_config['start_freq'],
+                        'range_end': scanner_config['end_freq']
                     })
                 except queue.Full:
                     pass
@@ -545,7 +557,9 @@ def scanner_loop_power():
                             'level': level,
                             'threshold': threshold,
                             'detected': snr >= snr_threshold,
-                            'progress': progress
+                            'progress': progress,
+                            'range_start': scanner_config['start_freq'],
+                            'range_end': scanner_config['end_freq']
                         })
                     except queue.Full:
                         pass
@@ -591,7 +605,9 @@ def scanner_loop_power():
                             'modulation': mod,
                             'audio_streaming': False,
                             'level': level,
-                            'threshold': threshold
+                            'threshold': threshold,
+                            'range_start': scanner_config['start_freq'],
+                            'range_end': scanner_config['end_freq']
                         })
                     except queue.Full:
                         pass
diff --git a/static/js/modes/listening-post.js b/static/js/modes/listening-post.js
index 3a2a626..bc64675 100644
--- a/static/js/modes/listening-post.js
+++ b/static/js/modes/listening-post.js
@@ -616,11 +616,44 @@ function handleScannerEvent(data) {
 }
 
 function handleFrequencyUpdate(data) {
+    if (data.range_start !== undefined && data.range_end !== undefined) {
+        const newStart = parseFloat(data.range_start);
+        const newEnd = parseFloat(data.range_end);
+        if (Number.isFinite(newStart) && Number.isFinite(newEnd) && newEnd > newStart) {
+            scannerStartFreq = newStart;
+            scannerEndFreq = newEnd;
+            scannerTotalSteps = Math.max(1, Math.round(((scannerEndFreq - scannerStartFreq) * 1000) / (scannerStepKhz || 1)));
+
+            const rangeStart = document.getElementById('scannerRangeStart');
+            if (rangeStart) rangeStart.textContent = newStart.toFixed(1);
+            const rangeEnd = document.getElementById('scannerRangeEnd');
+            if (rangeEnd) rangeEnd.textContent = newEnd.toFixed(1);
+            const mainRangeStart = document.getElementById('mainRangeStart');
+            if (mainRangeStart) mainRangeStart.textContent = newStart.toFixed(1) + ' MHz';
+            const mainRangeEnd = document.getElementById('mainRangeEnd');
+            if (mainRangeEnd) mainRangeEnd.textContent = newEnd.toFixed(1) + ' MHz';
+
+            const startInput = document.getElementById('radioScanStart');
+            if (startInput && document.activeElement !== startInput) {
+                startInput.value = newStart.toFixed(3);
+            }
+            const endInput = document.getElementById('radioScanEnd');
+            if (endInput && document.activeElement !== endInput) {
+                endInput.value = newEnd.toFixed(3);
+            }
+        }
+    }
+
     const range = scannerEndFreq - scannerStartFreq;
     if (range <= 0) {
         return;
     }
 
+    const effectiveRange = scannerEndFreq - scannerStartFreq;
+    if (effectiveRange <= 0) {
+        return;
+    }
+
     const hasProgress = data.progress !== undefined && Number.isFinite(data.progress);
     const freqValue = (typeof data.frequency === 'number' && Number.isFinite(data.frequency))
         ? data.frequency
@@ -648,7 +681,7 @@ function handleFrequencyUpdate(data) {
             }
         }
         lastScanFreq = freqValue;
-        progressValue = (freqValue - scannerStartFreq) / range;
+        progressValue = (freqValue - scannerStartFreq) / effectiveRange;
         lastScanProgress = Math.max(0, Math.min(1, progressValue));
     } else {
         if (scannerMethod === 'power') {
@@ -664,7 +697,7 @@ function handleFrequencyUpdate(data) {
         && freqValue >= (scannerStartFreq - freqTolerance)
         && freqValue <= (scannerEndFreq + freqTolerance))
         ? freqValue
-        : scannerStartFreq + (clampedProgress * range);
+        : scannerStartFreq + (clampedProgress * effectiveRange);
     const freqStr = displayFreq.toFixed(3);
 
     const currentFreq = document.getElementById('scannerCurrentFreq');