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Author Topic: Unknown Ship in Distress 12577 khz USB/DSC, 22:01 11 April 2020  (Read 487 times)

Offline jasmine

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having really gotten into decoding digital signals thanks to help from Josh i've been routinely decoding HFDL from air and ground stations. today i tried something different and begun decoding GMDSS DSC on 12577khz. this afternoon was my first time doing this and i think i may have picked up a ship in distress. at least that's what the software/message told me:



TIME: 2020-04-11 22:01:23 FREQ: 12577.0 DIST: -- Km
SYMB: 112 ~~~ ~~~ ~~~ 088 ~~~ 067 112 ~~~ ~~~ 043 020 ~~~ ~~~ ~~~ ~~~ 000 000 000 000
 FMT: DIS
 CAT: DIS
FROM: SHIP,~~~~88~~6,???
 TC1: --
 TC2: --
FREQ: --
 POS: ????
 EOS: UNK/ERR
cECC: 36 ERR
DATA: TIME -1:-1, POSITION ????, NATURE: EPIRB
 
RAW FEC: 125 108 125 107 125 ~~~ 120 ~~~ 120 ~~~ 089 ~~~ ~~~ ~~~ ~~~ ~~~ 007 ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ 104 009 ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ 112 ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ 067 088 112 ~~~ ~~~ ~~~ ~~~ ~~~ 043 ~~~ 020 ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~

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Offline Josh

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Re: Unknown Ship in Distress 12577 khz USB/DSC, 22:01 11 April 2020
« Reply #1 on: April 12, 2020, 2103 UTC »
Nice, dunno if I ever caught an emergency dsc sig before. Will have to fire up a decoder for dsc, what with nothing on hfdl these days.
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Offline jasmine

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Re: Unknown Ship in Distress 12577 khz USB/DSC, 22:01 11 April 2020
« Reply #2 on: April 14, 2020, 1759 UTC »
Nice, dunno if I ever caught an emergency dsc sig before. Will have to fire up a decoder for dsc, what with nothing on hfdl these days.

having so little HFDL traffic is what led me to looking to decode DSC, that plus i had never done it before and since we're all locked down why not? :)
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Offline Josh

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Re: Unknown Ship in Distress 12577 khz USB/DSC, 22:01 11 April 2020
« Reply #3 on: April 14, 2020, 1953 UTC »
Along with 12577 for day dx, I found 6312 best for nites.
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Offline Pigmeat

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Re: Unknown Ship in Distress 12577 khz USB/DSC, 22:01 11 April 2020
« Reply #4 on: April 14, 2020, 2029 UTC »
I haven't heard one of those in decades. Nice catch. I wouldn't want to be on ship or in the air.
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Offline jasmine

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Re: Unknown Ship in Distress 12577 khz USB/DSC, 22:01 11 April 2020
« Reply #5 on: April 14, 2020, 2350 UTC »
Along with 12577 for day dx, I found 6312 best for nites.

thanks i'll sit on 6312 tonight. usually i put it on 4207.5 and get a lot of activity. 12577 is good for me when there isn't interference but something on my block often puts out some bad interference there so i opt for either 16804.5 mid day or 8414.5
« Last Edit: April 14, 2020, 2354 UTC by jasmine »
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