diff --git a/html/doalles.js b/html/doalles.js
index b989314..c6d991e 100644
--- a/html/doalles.js
+++ b/html/doalles.js
@@ -288,6 +288,8 @@ function updateSats()
             let wantIt = false;
             if(d3.select("#GalE1").property("checked") && arr[n].gnssid==2 && arr[n].sigid == 1)
                 wantIt = true;
+            if(d3.select("#GalE5a").property("checked") && arr[n].gnssid==2 && arr[n].sigid == 6)
+                wantIt = true;
             if(d3.select("#GalE5b").property("checked") && arr[n].gnssid==2 && arr[n].sigid == 5)
                 wantIt = true;
             if(d3.select("#GPSL1CA").property("checked") && arr[n].gnssid==0 && arr[n].sigid == 0)
diff --git a/html/index.html b/html/index.html
index 0bd36cb..8f2bb48 100644
--- a/html/index.html
+++ b/html/index.html
@@ -10,6 +10,7 @@
   <div class="centered">
     <hr/>
     <input type="checkbox"  id="GalE1" onclick="updateSats();">  <label for="GalE1">Galileo E1</label> &nbsp;&nbsp;
+    <input type="checkbox"  id="GalE5a" onclick="updateSats();">  <label for="GalE5a">Galileo E5a</label> &nbsp;&nbsp;
     <input type="checkbox"  id="GalE5b" onclick="updateSats();">  <label for="GalE5b">Galileo E5b</label> &nbsp;&nbsp;
     <input type="checkbox"  id="BeiDouB1I" onclick="updateSats();">  <label for="BeiDouB1I">BeiDou B1I</label> &nbsp;&nbsp;
     <input type="checkbox"  id="BeiDouB2I" onclick="updateSats();">  <label for="BeiDouB2I">BeiDou B2I</label> &nbsp;&nbsp;