Hi.
16805,0 kHz is irritating, as you cauhgt an FSK modulated signal. The central frequency for that is 16804,5 kHz and it is a well known DSC-channel in the maritime mobile service.
There are many stations from Chile listed there but I'd guess it is either
Antofagasta Zonal Radio (CBA) or
Valparaiso Playa Ancha Radio (CBV). A very hot catch could be
Bahia Fildes Radio (CBZ22) from the Antarctic (-62.196342, -58.959383 / GC07MT).
Looking on Argentine there are the following stations on 16804,5:
- Buenos Aires Prefectura Naval Radio L2G
- Mar del Plata Prefectura Naval Radio L2U
- Comodoro Rivadavia Prefectura Naval Radio L3B
- Ushuaia Prefectura Naval Radio L3P
- Argentina Radio LSD836
(Source: Admirality LIst of Radio Signals, ITU, IMO GISIS)
On the other hand there is NAVTEX-traffic on 16806,5 kHz but I have no stations from Chile listed there. But from Argentine there are tow entries in my database:
- Buenos Aires Prefectura Naval Radio L2B / Sending NAVTEX at 1400z
- Buenos Aires Prefectura Naval Radio L2C / Sending NAVTEX at 0030,0300,1000,1400,1530,1900,2100 (all times Zulu)
Just a tipp: ALways use the CF for FSK modulated transmissions - that may help to identify the station you caught much more easier.

Hope this helps.