This chamber's radio is underneath the third moving platform. You can only grab it when you've activated all three.
Where do I take it?
The light will turn green when the radio is next to the incinerator.
To reach it, you'll need to carry the radio as you jump across the three platforms and jump down into the incinerator room.
Guide help
This is the low-spoiler guide for "Transmission Received (Radio 19/26)" puzzle in Portal. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.
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