diff --git a/peak_det_eval.grc b/peak_det_eval.grc
index 986a55c..213e8bb 100644
--- a/peak_det_eval.grc
+++ b/peak_det_eval.grc
@@ -205,7 +205,7 @@
     </param>
     <param>
       <key>value</key>
-      <value>samp_rate/4</value>
+      <value>0</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -241,7 +241,7 @@
     </param>
     <param>
       <key>start</key>
-      <value>samp_rate/32</value>
+      <value>-samp_rate/2</value>
     </param>
     <param>
       <key>step</key>
@@ -249,7 +249,7 @@
     </param>
     <param>
       <key>stop</key>
-      <value>samp_rate/1</value>
+      <value>samp_rate/2</value>
     </param>
     <param>
       <key>rangeType</key>
@@ -394,7 +394,7 @@
     </param>
     <param>
       <key>freq</key>
-      <value>samp_rate/2</value>
+      <value>-samp_rate/4</value>
     </param>
     <param>
       <key>_coordinate</key>
@@ -437,7 +437,7 @@
     <key>analog_sig_source_x</key>
     <param>
       <key>amp</key>
-      <value>0.1</value>
+      <value>0</value>
     </param>
     <param>
       <key>alias</key>
@@ -520,7 +520,7 @@
     </param>
     <param>
       <key>freq</key>
-      <value>samp_rate/8</value>
+      <value>samp_rate/4</value>
     </param>
     <param>
       <key>_coordinate</key>
@@ -1093,7 +1093,7 @@
     </param>
     <param>
       <key>alpha_s</key>
-      <value>0.99</value>
+      <value>0.2</value>
     </param>
     <param>
       <key>alias</key>
@@ -1137,7 +1137,7 @@
     </param>
     <param>
       <key>peak_height_min</key>
-      <value>20</value>
+      <value>18</value>
     </param>
     <param>
       <key>peak_width_max</key>
@@ -1145,7 +1145,7 @@
     </param>
     <param>
       <key>peak_width_min</key>
-      <value>25</value>
+      <value>5</value>
     </param>
     <param>
       <key>vlen</key>