Very Low Frequency (VLF) radio transmitter <a href="https://en.wikipedia.org/wiki/Control_panel_(engineering)" class="extiw" title="w:Control panel (engineering)">control panel</a>. Now on display at the <a href="https://en.wikipedia.org/wiki/Hack_Green_Secret_Nuclear_Bunker" class="extiw" title="w:Hack Green Secret Nuclear Bunker">Hack Green Secret Nuclear Bunker</a> museum, this equipment was used to control the transmitters located at <a href="https://en.wikipedia.org/wiki/Rugby_Radio_Station" class="extiw" title="w:Rugby Radio Station">Rugby (GBR)</a> for secure radio communications to ships and nuclear submarines.
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/davidcjones/">David Jones</a>
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