RTTY – great online tutorial from AA5AU
Filed Under (Digital Communications) by Jonathan on 08-01-2010
Don, AA5AU has a great “Getting started with RTTY” page complete with full tutorials to get you started.
If you have ever wanted to give this digital mode a try, you have no excuse not to anymore. Don has written a full tutorial on RTTY using MMTTY software. The screen shot to the right is from MMTTY.
But, what is RTTY? From Don’s site:
RTTY is Baudot code (see http://chem.ch.huji.ac.il/~eugeniik/history/baudot.html for excellent information on Mr. Baudot and his code). More specifically, on the Amateur HF bands, it’s 5 bit baudot meaning that every character consists of five bits, either mark or space (in actuality Baudot is 8 bits because a start bit and two stop bits are added for synchronization see http://www.aa5au.com/gettingstarted/rtty_diddles_technical.htm). In general, a baud rate of 45.45 baud is used on HF. 45.45 baud is the equivalent of 60 wpm. Even though 45.45 is standard, you will occasionally come across a RTTY signal at a different speed. Ed, P5/4L4FN, preferred to run 50 baud rate (66 wpm) when he was active on RTTY from North Korea. 75 baud (100 wpm) can also be used on the Amateur HF bands.
The nice thing about RTTY is you don’t need a whizbang station with everything including a linear to have loads of fun. In fact, in the few times I’ve dabbled with RTTY, low power (50 watts) worked better for me. You can learn more about why on the tutorial.
The page has detailed instructions on installing MMTTY and making your first contacts with RTTY. Pages are printable for offline reading (in PDF) as well. Page topics include:
Page 1 - Downloading MMTTY
Page 2 – Running MMTTY
Page 3 – Receiving RTTY Discussion
Page 4 – Receiving RTTY with MMTTY
Page 5 – Transmitting RTTY Discussion
Page 6 – Transmitting AFSK with MMTTY
Page 7 – Transmitting FSK with MMTTY
Page 8 – Specifics -USB adapters, EXTFSK
Page 9 – Commercial Interfaces
Check out Don’s site at: http://www.aa5au.com/rtty.html
