Funny that this is top of HN right. Spent a ton of time in this repo lately trying to understand how modems work. Fascinating how we can use waves to send data (audio or rf). So much of the world relies on these modulation/demodulation approaches.
Also, it was only a few days ago I finally learned that modem is short for MOdulator DEModulator. My mind was blown.
You might be interested to know about the Morse keying requirement for Ham radio licenses before the early 90s.
I think ham radio licenses lost popularity between then and approx 2018. Demonstrating fluency with Morse was necessary for a license long ago. Nowadays, there’s a renewal of interest but many new Ham operators can write a Morse codec faster than they can learn fluency by hand. I think the requirement for demonstrating Morse by hand in order to obtain a HF license will be dropped if it isn’t already.
Hah, I had to learn the most basic understanding of Morse for my private pilot certificate. When I finally got to the checkride and had to fly off a VOR radial I asked the examiner if he wanted me to identify the station (by the 3 letter Morse code broadcast) and he said nah.
> I think the requirement for demonstrating Morse by hand in order to obtain a HF license will be dropped if it isn’t already
The Morse requirement was dropped by the FCC for all license classes back in 2006.
But even with SDR making radio experimentation easier and more rewarding than ever ham radio seems to be continuing its slow decline and the average age of operations continues to rise... and we continue to lose spectrum (e.g. we just lost the 9cm band).
Also, it was only a few days ago I finally learned that modem is short for MOdulator DEModulator. My mind was blown.