Science Operations
 
 

SOHO Telemetry Subformat Definitions

There are currently five telemetry subformats:

Submode 2
LASCO/EIT high rate
Submode 3
CDS high rate
Submode 4
SUMER high rate
Submode 5
Nominal Submode
Submode 6
Same as Submode 5 except LASCO/EIT acquires all SUMER telemetry

There have been several modifications to the telemetry subformats after launch. A history of changes is outlined below starting with the current submode definitions. By clicking on the anchors below, tables of telemetry allocations can be obtained:

PRESENT
After SOHO recovery and ESRs during early 1999, it was decided to only Patch Submode #1 to the current Submode #6, and upload programmable Submode #5. No submode #2 and #3 patches will be reloaded until needed.
Jun 25 - Aug 8, 1998
No telemetry, see SOHO Recovery pages.
Mar 3 - Jun 25, 1998
On Mar 3, a spacecraft warm startup occurred and submodes went back to original launch configurations. On Mar 5, all submodes went back to the previous subformat definitions.
Mar 2 - 3, 1998
Submode 3 was altered as follows: LASCO/EIT gained 3 packets (32 —> 35 packets) in Submode 3. CDS lost 7 packets (144 —> 137 packets) in Submode 3. However, after spending some time in this submode, it was determined that a LASCO/EIT on-board software load will be needed in order for their instruments to respond optimally to the patch. Decided to go back to previous configuration.
Sep 25/26, 1997 - Mar 2, 1998
Submodes 3 and 2 were upgraded respectively. LASCO/EIT gained 8 additional packets (24 —> 32 packets) in Submode 3. CDS gained 8 additional packets (12 —> 20 packets) in Submode 2
Feb 10/11 - Sep 25/26 1997
Submodes 5 and 6 were added respectively. Submode 5 was added into the programmable submode. Submode 5 added 12 extra packets to LASCO/EIT (24 —> 36 packets) and became the new "nominal" operating submode replacing Submode 1. Submode 1 was patched, to give all SUMER science telemetry to LASCO/EIT and renamed as Submode 6.
Launch - Feb 10/11, 1997
Original configuration of Submodes 1, 2, 3, 4 were used