Recording of ground communications during <a href="https://en.wikipedia.org/wiki/Mercury-Redstone_4" class="extiw" title="en:Mercury-Redstone 4">Mercury-Redstone 4</a>. Includes commentary and communications in the <a href="https://en.wikipedia.org/wiki/Mercury_Control_Center" class="extiw" title="en:Mercury Control Center">Mercury Control Center</a>, with radio transmissions audible in the background. NASA historical audio archive reel 371-AAI.
NASA
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