Stabilize sweep progress updates

routes/listening_post.py

@@ -525,6 +525,11 @@ def scanner_loop_power():
 
             # Process segments in ascending frequency order to avoid backtracking in UI
             segments.sort(key=lambda s: s[0])
+            total_bins = sum(len(seg[3]) for seg in segments)
+            if total_bins <= 0:
+                time.sleep(0.2)
+                continue
+            global_index = 0
 
             for sweep_start, sweep_end, sweep_bin, bin_values in segments:
                 # Noise floor (median)
@@ -545,16 +550,19 @@ def scanner_loop_power():
                     snr = val - noise_floor
                     level = int(max(0, snr) * 100)
                     threshold = int(snr_threshold * 100)
+                    progress = min(1.0, global_index / max(1, total_bins - 1))
                     try:
                         scanner_queue.put_nowait({
                             'type': 'scan_update',
                             'frequency': scanner_current_freq,
                             'level': level,
                             'threshold': threshold,
-                            'detected': snr >= snr_threshold
+                            'detected': snr >= snr_threshold,
+                            'progress': progress
                         })
                     except queue.Full:
                         pass
+                    global_index += emit_stride
 
                 # Detect peaks (clusters above threshold)
                 peaks = []

static/js/modes/listening-post.js

@@ -15,7 +15,6 @@ let scannerCycles = 0;
 let scannerStartFreq = 118;
 let scannerEndFreq = 137;
 let scannerSignalActive = false;
-let lastScanFreq = null;
 
 // Audio state
 let isAudioPlaying = false;
@@ -182,7 +181,6 @@ function startScanner() {
     scannerEndFreq = endFreq;
     scannerFreqsScanned = 0;
     scannerCycles = 0;
-    lastScanFreq = null;
 
     // Update sidebar display
     updateScannerDisplay('STARTING...', 'var(--accent-orange)');
@@ -296,7 +294,6 @@ function stopScanner() {
             isScannerPaused = false;
             scannerSignalActive = false;
             currentSignalLevel = 0;
-            lastScanFreq = null;
 
             // Re-enable listen button (will be in local mode after stop)
             updateListenButtonState(false);
@@ -575,18 +572,6 @@ function handleScannerEvent(data) {
 function handleFrequencyUpdate(data) {
     const freqStr = data.frequency.toFixed(3);
 
-    // Prevent jitter from out-of-order sweep segments
-    if (lastScanFreq !== null) {
-        const range = scannerEndFreq - scannerStartFreq;
-        if (range > 0 && data.frequency < lastScanFreq) {
-            const drop = lastScanFreq - data.frequency;
-            if (drop < range * 0.5) {
-                return; // ignore backward blip within sweep
-            }
-        }
-    }
-    lastScanFreq = data.frequency;
-
     const currentFreq = document.getElementById('scannerCurrentFreq');
     if (currentFreq) currentFreq.textContent = freqStr + ' MHz';
 
@@ -594,7 +579,9 @@ function handleFrequencyUpdate(data) {
     if (mainFreq) mainFreq.textContent = freqStr;
 
     // Update progress bar
-    const progress = ((data.frequency - scannerStartFreq) / (scannerEndFreq - scannerStartFreq)) * 100;
+    const progress = (data.progress !== undefined)
+        ? (data.progress * 100)
+        : ((data.frequency - scannerStartFreq) / (scannerEndFreq - scannerStartFreq)) * 100;
     const progressBar = document.getElementById('scannerProgressBar');
     if (progressBar) progressBar.style.width = Math.max(0, Math.min(100, progress)) + '%';