View source for Frequency hopping


Do you remember actress Hedy Lamarr?

She got a patent on the basis of wifi. (1942)

"frequency hopping, spread-spectrum communication system”

During WWII torpedos were radio controlled 

and could be jammed with  the right frequency.

They were to use a player piano roll 

to change frequency on a predetermined  sequence.

It was never placed in use.

Frequency hopping was used on some aircraft radio.

In my early ham radio days, 

surplus military radioes were available. 

The ART13 had motors to drive the tuning controls. 

It had a channel selector A,B,C etc 

so that all controls were preset and  the  channel could be changed on an arranged schedule.

That was the good old days.

Change channel, hear the motors whir, 

and you are tuned up on a new frequency.

No one wants that now.

Not enough room for the power supply.

Now, connect your ham radio to the rpi and talk over the internet.

Why, you do not  even have to know code anymore.

Who wants  to run CW

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