diff --git a/tabs/auxiliary_configuration.js b/tabs/auxiliary_configuration.js
index fa73fced..eeea8f2d 100755
--- a/tabs/auxiliary_configuration.js
+++ b/tabs/auxiliary_configuration.js
@@ -1,3 +1,5 @@
+'use strict';
+
 // TODO: rework box_highlight & update_ui to accept flexible amount of aux channels
 tabs.auxiliary_configuration = {};
 tabs.auxiliary_configuration.initialize = function(callback) {
diff --git a/tabs/cli.js b/tabs/cli.js
index 73d9b680..cdaff5e7 100644
--- a/tabs/cli.js
+++ b/tabs/cli.js
@@ -1,3 +1,5 @@
+'use strict';
+
 var CLI_active = false;
 var CLI_valid = false;
 
diff --git a/tabs/default.js b/tabs/default.js
index 941f67f5..125ebd1c 100644
--- a/tabs/default.js
+++ b/tabs/default.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.default = {};
 tabs.default.initialize = function(callback) {
     GUI.active_tab_ref = this;
diff --git a/tabs/gps.js b/tabs/gps.js
index c4ec546c..777d3579 100644
--- a/tabs/gps.js
+++ b/tabs/gps.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.gps = {};
 tabs.gps.initialize = function(callback) {
     GUI.active_tab_ref = this;
diff --git a/tabs/initial_setup.js b/tabs/initial_setup.js
index b9eb129b..2ef932f3 100644
--- a/tabs/initial_setup.js
+++ b/tabs/initial_setup.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.initial_setup = {
     yaw_fix: 0.0
 };
diff --git a/tabs/motor_outputs.js b/tabs/motor_outputs.js
index 8438df31..37af7738 100644
--- a/tabs/motor_outputs.js
+++ b/tabs/motor_outputs.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.motor_outputs = {};
 tabs.motor_outputs.initialize = function(callback) {
     GUI.active_tab_ref = this;
@@ -99,7 +101,7 @@ tabs.motor_outputs.initialize = function(callback) {
     }
 
     function drawGraph(graphHelpers, data, sampleNumber) {
-        svg = d3.select(graphHelpers.selector);
+        var svg = d3.select(graphHelpers.selector);
 
         if (graphHelpers.dynamicHeightDomain) {
             var limits = [];
diff --git a/tabs/pid_tuning.js b/tabs/pid_tuning.js
index f839f729..d641d134 100644
--- a/tabs/pid_tuning.js
+++ b/tabs/pid_tuning.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.pid_tuning = {};
 tabs.pid_tuning.initialize = function(callback) {
     GUI.active_tab_ref = this;
diff --git a/tabs/receiver.js b/tabs/receiver.js
index 125f81d1..9bfa8541 100644
--- a/tabs/receiver.js
+++ b/tabs/receiver.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.receiver = {};
 tabs.receiver.initialize = function(callback) {
     GUI.active_tab_ref = this;
diff --git a/tabs/sensors.js b/tabs/sensors.js
index 47ebe7b4..3f4e526b 100644
--- a/tabs/sensors.js
+++ b/tabs/sensors.js
@@ -1,3 +1,5 @@
+'use strict';
+
 tabs.sensors = {};
 tabs.sensors.initialize = function(callback) {
     GUI.active_tab_ref = this;
@@ -102,7 +104,7 @@ tabs.sensors.initialize = function(callback) {
     }
 
     function drawGraph(graphHelpers, data, sampleNumber) {
-        svg = d3.select(graphHelpers.selector);
+        var svg = d3.select(graphHelpers.selector);
 
         if (graphHelpers.dynamicHeightDomain) {
             var limits = [];
diff --git a/tabs/servos.js b/tabs/servos.js
index f7d4ccf4..d794459f 100644
--- a/tabs/servos.js
+++ b/tabs/servos.js
@@ -4,6 +4,7 @@
     from multiwii is so horrible, obstructive and non dynamic, not to mention it doesn't make any sense
     that there was just no other way around this then hardcoding/implementing each model separately.
 */
+'use strict';
 
 tabs.servos = {};
 tabs.servos.initialize = function(callback) {