Bob,
Thanks for the info.
They are not plain text.like other ACARS-type messages. Even the standard log-on "Welcome" message cannot be seen as plain text over the air.
Any idea what the format is ? Hexadecimal ? I'm wondering if there is some way to decode it ? Maybe they use some sort of encryption protocol and I'm just wasting my time ?
I'm located close to a 136.975 transmitter and can hear the databursts, now I just have to figure out how to get multiPSK to work.
Do you have any examples handy you can paste here just so I can see what the multiPSK output is supposed to look like ? Or hints on receiving it ?
Thanks for any info.
DJ
FYI related NOTAMS from Toronto Center ....
A2772/14 NOTAMN
Q) CZYZ/QCDXX/IV/NBO/E /000/999/4729N08055W999
A) CZYZ
B) 1404121200
C) PERM
E) WEF 2014 APR 12 1300
CPDLC WELCOME MESSAGE WILL BE IMPLEMENTED IN TORONTO ACC.
TORONTO ACC WILL COMMENCE USE OF THE CPDLC WELCOME MESSAGE WITHIN
HIGH LEVEL AIRSPACE FL290 AND ABOVE. FOLLOWING A SUCCESSFUL CPDLC
CONNECTION WITH TORONTO THE FOLLOWING MESSAGE WILL BE SENT TO ACFT
VIA CPDLC:
UM169 - FREE TEXT 'THIS IS AN AUTOMATED MESSAGE TO CONFIRM CPDLC
CONTACT WITH TORONTO CENTRE'.
THE ATSU GROUND SYSTEM IN TORONTO IS EXPECTING A RESPONSE TO THE
WELCOME MESSAGE. UPON RECEIPT OF THE WELCOME MESSAGE AIRCREW ARE
REMINDED TO RESPOND WITH DM003 - ROGER
A4471/14 NOTAMR A2776/14
Q) CZYZ/QCDXX/IV/NBO/E /000/999/4729N08055W999
A) CZYZ
B) 1406091318
C) PERM
E) CZYZ WEF 2014 APR 12 1300
CPDLC PHASE 1, 2, AND 3 FOR TORONTO ACC IMPLEMENTED WITHIN HIGH
LEVEL AIRSPACE FL290 AND ABOVE AS PER AIC 15/14.
ONLY THE FOLLOWING DOWNLINK MESSAGES WILL BE SUPPORTED BY TORONTO
ACC:
DM0 - WILCO
DM1 - UNABLE
DM2 - STANDBY
DM3 - ROGER
DM4 - AFFIRM
DM5 - NEGATIVE
DM6 - REQUEST (ALT)
DM9 - REQUEST CLIMB TO (ALT)
DM10 - REQUEST DESCENT TO (ALT)
DM18 - REQUEST (SPEED)
DM20 - REQUEST VOICE CONTACT
DM21 - REQUEST VOICE CONTACT (FREQ)
DM22 - REQUEST DIRECT TO (POS)
DM28 - LEAVING (ALT)
DM29 - CLIMBING TO (ALT)
DM30 - DESCENDING TO (ALT)
DM32 - PRESENT ALTITUDE (ALT)
DM34 - PRESENT SPEED (SPEED)
DM37 - LEVEL (ALT)
DM38 - ASSIGNED LEVEL (LEVEL)
DM39 - ASSIGNED SPEED (SPEED)
DM47 - SQUAWKING (CODE)
DM55 - PAN PAN PAN
DM56 - MAYDAY MAYDAY MAYDAY
DM57 - (FUEL) (FUEL2) FUEL REMAINING (SOULS) SOULS ON BOARD
DM58 - CANCEL EMERGENCY
DM60 - OFFSETTING (DOFF) (DIR) OF ROUTE
DM61 - DESCENDING TO (ALT)
DM62 - ERROR (ERROR INFORMATION)
DM63 - NOT CURRENT DATA AUTHORITY
DM64 - (ICAO FACILITY DESIGNATION)
DM65 - DUE WEATHER
DM66 - DUE AIRCRAFT PERFORMANCE
DM67 - FREE TEXT
DM80 - DEVIATING (DOFF) (DIR) OF ROUTE
ANY DOWNLINK MESSAGE OTHER THAN THE ABOVE WILL GENERATE A 'MESSAGE
NOT SUPPORTED BY THIS FACILITY' RESPONSE FROM THE GROUND SYSTEM.