diff --git a/app/src/main/java/xdsopl/robot36/Demodulator.java b/app/src/main/java/xdsopl/robot36/Demodulator.java
index e050bcb..3171236 100644
--- a/app/src/main/java/xdsopl/robot36/Demodulator.java
+++ b/app/src/main/java/xdsopl/robot36/Demodulator.java
@@ -18,6 +18,10 @@ public class Demodulator {
 	private final Phasor baseBandOscillator;
 	private final Delay syncPulseDelay;
 	private final Delay scanLineDelay;
+	private final int syncPulseSamples;
+	private float syncPulseMaxLevel;
+	private int syncPulseMaxPosition;
+	private int syncPulseCounter;
 	private Complex baseBand;
 	private Complex syncPulse;
 	private Complex scanLine;
@@ -34,8 +38,8 @@ public class Demodulator {
 		int scanLineFilterSamples = (int) Math.round(0.443 * sampleRate / scanLineCutoff) | 1;
 		scanLineFilter = new ComplexMovingAverage(scanLineFilterSamples);
 		double syncPulseSeconds = 0.009;
-		int syncPulseFilterSamples = (int) Math.round(syncPulseSeconds * sampleRate) | 1;
-		syncPulseFilter = new ComplexMovingAverage(syncPulseFilterSamples);
+		syncPulseSamples = (int) Math.round(syncPulseSeconds * sampleRate) | 1;
+		syncPulseFilter = new ComplexMovingAverage(syncPulseSamples);
 		float lowestFrequency = 1100;
 		float highestFrequency = 2300;
 		float cutoffFrequency = (highestFrequency - lowestFrequency) / 2;
@@ -49,7 +53,7 @@ public class Demodulator {
 		scanLineOscillator = new Phasor(-(grayFrequency - centerFrequency), sampleRate);
 		int syncPulseDelaySamples = (powerWindowSamples - 1) / 2;
 		syncPulseDelay = new Delay(syncPulseDelaySamples);
-		int scanLineDelaySamples = (powerWindowSamples - 1) / 2 + (syncPulseFilterSamples - 1) / 2 - (scanLineFilterSamples - 1) / 2;
+		int scanLineDelaySamples = (powerWindowSamples - 1) / 2 + (syncPulseSamples - 1) / 2 - (scanLineFilterSamples - 1) / 2;
 		scanLineDelay = new Delay(scanLineDelaySamples);
 		syncPulseTrigger = new SchmittTrigger(0.17f, 0.19f);
 		baseBand = new Complex();
@@ -66,10 +70,25 @@ public class Demodulator {
 			float scanLineValue = scanLineDelay.push(scanLineDemod.demod(scanLine));
 			float syncPulseLevel = Math.min(Math.max(syncPulseValue, 0), 1);
 			float scanLineLevel = Math.min(Math.max(0.5f * (scanLineValue + 1), 0), 1);
-			if (syncPulseTrigger.latch(syncPulseLevel))
-				buffer[i] = -syncPulseLevel;
-			else
+			if (syncPulseTrigger.latch(syncPulseLevel)) {
+				if (syncPulseMaxLevel < syncPulseLevel) {
+					syncPulseMaxLevel = syncPulseLevel;
+					syncPulseMaxPosition = syncPulseCounter;
+				}
+				++syncPulseCounter;
+				buffer[i] = syncPulseLevel;
+			} else if (syncPulseCounter > 0 && syncPulseCounter < syncPulseSamples) {
+				int offset = syncPulseCounter - syncPulseMaxPosition;
+				if (offset <= i)
+					buffer[i - offset] = -1;
+				syncPulseCounter = 0;
+				syncPulseMaxLevel = 0;
 				buffer[i] = scanLineLevel;
+			} else {
+				syncPulseCounter = 0;
+				syncPulseMaxLevel = 0;
+				buffer[i] = scanLineLevel;
+			}
 		}
 	}
 }
diff --git a/app/src/main/java/xdsopl/robot36/MainActivity.java b/app/src/main/java/xdsopl/robot36/MainActivity.java
index ff193be..8a4f9e8 100644
--- a/app/src/main/java/xdsopl/robot36/MainActivity.java
+++ b/app/src/main/java/xdsopl/robot36/MainActivity.java
@@ -62,15 +62,11 @@ public class MainActivity extends AppCompatActivity {
 
 	private void visualizeSignal() {
 		for (float v : recordBuffer) {
-			int pixelColor = 0x00010101;
-			float level = v;
-			if (v < 0) {
-				level = -v;
-				pixelColor = 0x00000100;
+			int pixelColor = 0xff00ff00;
+			if (v >= 0) {
+				int intensity = (int) Math.round(255 * Math.sqrt(v));
+				pixelColor = 0xff000000 | 0x00010101 * intensity;
 			}
-			int intensity = (int) Math.round(255 * Math.sqrt(level));
-			pixelColor *= intensity;
-			pixelColor |= 0xff000000;
 			scopePixels[scopeWidth * curLine + curColumn] = pixelColor;
 			if (++curColumn >= scopeWidth) {
 				curColumn = 0;