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One day in the summer of 1940 a shipload of children was torpedoed, all hands lost, including 83 children At the time the German U-boats were on the verge of winning the war They seemed to be unsinkable because they easily outmaneuvered the outdated British torpedoes In times of crisis most of us feel powerless But a few discover in themselves unexpected strength and Hedy being Hedy, she said I'm gonna do something about that So in this article Hedy he says, 'I got the idea for my invention when I tried to think of some way to even the balance for the British' 'A radio-controlled torpedo I thought would do it.'

A torpedo launched on a given trajectory might need to be changed... redirected You want ideally you're launching boat or your submarine to communicate with the torpedo.

The problem is you can't control radio communications.

They're not secure.

Your enemy, if they are smart, finds the frequency with which you're talking to the torpedo and jams it.

Jamming. The Germans fill the air with radio interference.

She came up with the idea of a secret way of guiding that torpedo to the target that couldn't be interrupted.

That couldn't be jammed, that couldn't be messed with. It was secret.

Instead of just one transmit frequency communicating she said what have we change those frequencies constantly in sync Frequency hopping.

You couldn't jam it because you'd only jam a split second of it in a single frequency.

So frequency changed, frequency hop, frequency hop, frequency hop, that concept secured radio communications was brilliant.


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