Contestia is a digital mode directly derived from Olivia that is not quite as robust - but more of a compromise between speed and performance.
It was developed by Nick Fedoseev, UT2UZ, in 2005. It sounds almost identical to Olivia, can be configured in as many ways, but has essentially twice the speed.
Contestia has 40 formats just like Olivia - some of which are considered standard and they all have different characteristics. The formats vary in bandwidth (125,250,500,1000, and 2000hz) and number of tones used (2,4,8,16,32,64,128, or 256).
The standard Contestia formats (bandwidth/tones) are 125/4, 250/8, 500/16, 1000/32, and 2000/64.
The most commonly used formats right now seem to be 250/8, 500/16, and 1000/32.
How well does Contestia perform?
Contestia performs very well under weak signal conditions. It handles QRM, QRN, and QSB very well also. It decodes below the noise level but Olivia still outperforms it in this area by about 1.5 - 3db depending on configuration.
It is twice as fast as Olivia per configuration. It is an excellent weak signal, ragchew, QRP, and DX digital mode. When ragchewing under fair or better conditions it can be more preferable to many hams than Olivia because of the faster speed. For contests it might also be a good mode IF the even faster configurations such as 1000/8 or 500/4 are used.
Contestia get it's increased speed by using a smaller symbol block size (32) than Olivia (64) and by a using 6bit decimal character set rather than 7bit ASCII set that Olivia does.
Therefore, it has a reduced character set and does not print out in both upper and lower case (like RTTY). Some traffic nets might not want to use this mode because it does not support upper and lower case characters and extended characters found in many documents and messages. For normal digital chats and ham communications that does not pose any problem.
=========== Editorial commentary ===============
In my personal on the air tests and QSO's, Contestia has done real well and has already become my 2nd favorite mode - Olivia being my favorite. When the current sunspot cycle heats up and progresses Contestia may become my staple on the higher bands as they get more crowded and the signals get consistently stronger. 250/8 contestia, which runs at approx. 30wpm, is a great space saver over using 500/8 Olivia to achieve the same speed (About 30wpm) - AND Contestia 250/8 seems to have about the same S/N ratio (as far as reading into the noise) as Olivia 500/8 does.
Contestia 125/4 may become my favorite mode of ALL. So far - on the air tests and QSO's have shown it to be the SAME speed as Olivia 500/16 (about 20wpm) AND the same S/N ratio. The obvious advantage is that it is 4 times more narrow! Olivia 500/16 is more hardy - in as far as decoding through QRM (as most wider FEC modes do) but Contestia 125/4 does just as well with QRN and QSB - and with only a 125hz footprint it can duck between the QRM! IF you aren't obsessed with speed 125/4 makes an excellent relaxed chat mode, DX mode, and QRP mode (I had several LONG ragchews with my Flex 1500 running 4 watts with it).
The ONLY problem with 125/4 is that it is NOT obvious in ALL the major digital programs. It is NOT in MultiPSK unless it's been added lately - it certainly is not in any older versions.
It IS in Fldigi BUT not that obvious since there is NO menu item for it in the older versions - HOWEVER in the latest version there has NOW been a menu item added for it! It could always be set for 125/4 in the modem settings for Contestia BUT many casual (and some NOT so casual) operators thought the MENU choices were the ONLY choices for Contestia and Olivia.
It is also in MixW (if you get the DLL for extra modes and load them) BUT again it is NOT so obvious.
The latest version of DM780 (HRD) does support Contestia 125/4 and has a menu item for it.
AND ... until recently Contestia was NOT supported by the RSID. Patrick, creator of MultiPSK, has JUST recently added a RSID number for this mode and some others that were sorely needed.
So, Contestia 125/4 may just become a VERY popular mode when a lot more hams "discover" it - and find it when their RSID shows it on the screen! I, for one, will actively promote the use 125/4 (as well as 250/8) and hope others will too.
On the lower bands with higher noise levels Olivia will still be very important to me, though - since it can decode slightly farther into the noise. And when band conditions really stink - Olivia shines .....
Contestia is available in the same programs that support Olivia though a few have only recently added them in their latest BETA versions.
Ham Radio Deluxe (Beta ver. 5 has Contestia) - DM780 : The Ham Radio Deluxe suite consists of Ham Radio Deluxe which is a general rig control program that can be used by itself OR in conjunction with DM780. DM780 is a digital mode soundcard program that has quite a few modes and can be used by itself and/or with the Ham Radio Deluxe program. It is availabe ONLY on the Windows operating system and was made for Windows XP. Some people have ran it on earlier versions of Windows and Vista also but it is NOT supported fully except of Windows XP by the programmers. It is FREE and donations are encouraged. It currently is available ONLY in the BETA versions of Ham Radio Deluxe. The Ham Radio Deluxe home page is at : http://hrdsoftwarellc.com/
FLDigi: The FLDigi (beta ver. 3.20.ba has Contestia) program is available for the Linux, Windows (XP, Vista), and Macintosh operating systems and is FREE and open source. It also has multiple modes and built-in rig control capability. A deceptively simple and elegant user interface and works well with most any modern Linux distribution, Windows XP or Vista, or Macintosh OSX. It is available at : http://www.w1hkj.com
MultiPSK : The MultiPSK program is also FREE except for a few "Professional modes" included in it and is available only for Windows. It has a huge number of digital modes in it - some of which are ONLY currently available in this program. It works well with many older and newer computers and is worth having on the computer of any digital operator. The only caveat is that the user interface looks tremendously messy and daunting. It can discourage a user at first glance and looks very difficult but it's basic operation is fairly simple after you get used to the awful looking user interface. Contestia is in at least versions 4.0 and later. The program can be downloaded at : http://f6cte.free.fr/index_anglais.htm
MixW : The MixW program is NOT FREE and costs $50 to register online. It can be downloaded and used for 15 days before it must be registered. It is available only on Windows computers and has a large number of digital modes and has a DLL support file that can be downloaded to allow it to work with the Contestia mode. It can be found at : http://mixw.net/