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 .....
