Happy World Amateur Radio Day

An anonymous reader writes "There are over 700,000 ham radio licensees in the USA and about 2 ½ million worldwide. Today, this international community of wireless communications devotees are celebrating World Amateur Radio Day, recalling the advances Amateur Radio Service has made for modern man. Their theme for 2012 is Amateur Radio Satellites: Celebrating 50 Years in Space in remembrance of the launch of the first Amateur Radio satellites OSCAR 1 on December 12, 1961 and the launch of OSCAR 2 on June 2, 1962. Their ranks have included people like Steve Wozniak of Apple and Jack Kilby who invented the integrated circuit, Dr. Karl William Edmark who invented the heart defibrillator, Scott Durchslag, the Chief Operating Officer at Skype, and Dr. John Grunsfeld of NASA and the Hubble Space Telescope. This is the 87th anniversary of the foundation."

Amateur Radio keeps getting better!

[r_pattonII]

Amateur Radio has evolved greatly since the early days of having huge receivers and transmitters. Today we have so many different modes - CW, PSK31, APRS, SSB, etc on many different bands with just a transceiver. We can even do satellites and even low power (QRP) operations with a transmitter as small as a tuna can! The best part is meeting people all over the world who share this great hobby. I am excited to see where it goes from here and the technologies it will bring for the future from the individual who has a "homebrew" project to the commercial radio manufacturers and other companies who provide us the "candy" we love to play with!

Re:Amateur Radio keeps getting better!

[StatureOfLiberty]

Software defined radios digitally sample incoming signals. They then process those signals via software algorithms rather than electronic circuitry. Some radios can actually sample huge regions of the radio frequency spectrum (one amateur radio receiver I am aware of can watch a 60 MHz spectrum). They can actually decode many signals at the same time. So, for example, you could be decoding and watching hundreds of CW conversations (morse code) happening across the spectrum at the same time.

All the hardware has to do is digitize the radio spectrum being sampled. All of the remaining processing can be changed by replacing software. Previously, changing the processing of the signals meant replacing or adding electronic circuits.

The algorithms are quite sophisticated. Signals can be isolated for better reception or fairly easily excluded in the case of interference. This has resulted in a tremendous improvement in radio receivers especially in recent years. Neat stuff.