diff --git a/html/images/icons/greyscale/current.png b/html/images/icons/greyscale/current.png
index 952822c76..5c47df19d 100644
Binary files a/html/images/icons/greyscale/current.png and b/html/images/icons/greyscale/current.png differ
diff --git a/html/images/icons/greyscale/frequencies.png b/html/images/icons/greyscale/frequencies.png
index 15ef7c38b..b7a2c1d31 100644
Binary files a/html/images/icons/greyscale/frequencies.png and b/html/images/icons/greyscale/frequencies.png differ
diff --git a/html/images/icons/greyscale/voltages.png b/html/images/icons/greyscale/voltages.png
index ff8e7338a..8ec29fc77 100644
Binary files a/html/images/icons/greyscale/voltages.png and b/html/images/icons/greyscale/voltages.png differ