[GreenKeys] 20 M RTTY

[Dave Horsfall]

On Sat, 19 Sep 2015, John Vendely wrote:

> This is the Russian Navy 7-bit synchronous system known colloquially as 
> "36-50".  It has a 36 baud phasing sequence (sometimes mistaken for RYs) 
> followed by a preamble, then encrypted synchronous data.  50 baud with 
> 250 or 500 shift seems the most common, though others are occasionally 
> heard.  They sometimes send operator chat or ID's using FSK morse for 
> short periods.  These transmissions are all over the HF bands, and the 
> Russians seem to place them more or less wherever they please.  I have a 
> decoder for this mode, but have never observed any traffic in the clear.

Is (was) this the dreaded woodpecker?  The damned thing used to wander all 
over 20m; somewhere, I've got photographs of the thing, with its massive 
curtain arrays.

Oh, and Australia has its own woodpecker (i.e. OTHR) in Jindalee.

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."
To a shark, a swimmer looks very much like an injured seal, but tasting awful.