Portal 1: all radios and signals for the "Transmission Received" achievement

The location of every single radio and signal, in a compact and handy video, to help you with the achievement. It starts counting at 0 instead of 1, sorry about that. Here’s an article about this, too: https://strategywiki.org/wiki/Portal/Transmission_Received

Take the opportunity to connect and share this video with your friends and family if you find it useful.