Voyager In Space

 

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VOYAGER

Voyager LECP Data Analysis Handbook

 

Data File Descriptions

 

Master Rate (Tape) File Descriptions

 

Table 1. List of Header Block Contents

 

Item

Index

Name

Type

Description

1

1

SCID

I*1

Spacecraft Identification; 1=Voyager 1; 0=Voyager 2

2

 

MODE

I*1

Spacecraft telemetry mode 01(H)=CR2; 02(H)=CR3; 03(H)=CR4 04(H)=CR5; 05(H)=CR6; 07(H)=CR1 0A(H)=FE; 08(H)=NE; 18(H) or 1D(H) CR5A

Spacecraft Event Time-contains the Greenwich Mean of the first bit of the first spacecraft minor frame used in this LECP major frame

3

2

SCETH

I*2

Spacecraft Event Time, Hour-number of hours since the beginning of the current year plus 24. For the one hour interval Jan 1, 0000-0059 UT, SCET=24.  The Day of Year may be computed using DAY=(SCETH/24)

4

3

SCETS

I*2

Spacecraft Event Time (sec.) number of seconds since the beginning of the current hour

5

4

SCETMS

I*2

Spacecraft Event Time, (millisec) no. of milliseconds since the beginning of the current second.

6

5

SCETY

I*2

Spacecraft Event Time, Year-contains the last two digits of the current year (i.e., 77, 78)

7

6

G18ID

I*1

Group 18 Identification-contains the number of the LECP data group being readout at the end of the current LECP major frame

8

7

SCETF

I*1

Spacecraft Event Time Flag-indicates that the spacecraft clock has been corrected in some manner in the JPL processing.  Bit 0 indicates correction to the line count (0=none, 1=corrected) bit 1 the MOD60 counter and bit 2 the MOD2**16 counter.

9

7

MOD216

I*2

Mod2**16 Spacecraft Clock Word-contains the spacecraft Mod2**16 word for the first minor frame of the current record. This word is incremented every 48 minutes on the overflow of the Mod60 counter

10

8

M60

I*2

Mod60 Spacecraft Clock Word-contains the spacecraft Mod60 word for the first minor frame of the current record.  It  has a range of 0 to 59 and is incremented every 48 seconds at the overflow of the line counter

11

9

LC

I*2

Spacecraft Line Counter-contains the line count for the first minor frame in the current record LC ranges from 1 to 800(D) and is incremented every 0.06 seconds

12

10

S1

I*2

LECP Status Word 1, 10 bits, right justified

13

11

S2

I*2

LECP Status Word 2, 10 bits, right justified

14

12

S3

I*2

LECP Status Word 3, 10 bits, right justified

15

13

S4

I*2

LECP Status Word 4, 10 bits, right justified

16

14

S5

I*2

LECP Status Word 5, 10 bits, right Justified

17

15

S6

I*2

LECP Status Word 6, 10 bits, right justified

18

16

MP

I*2

LECP Motor Position-contains the motor position at the end of the current record.  Bit 0 is set if the status word indicates motor centering, it is zero otherwise.  Bits 1-3 contain the motor position with 0-7 corresponding to sector 1 thru 8 respectively.  MP=-1 if motor position is unknown

19

17

NMS

I*2

Number of Motor Steps-indicates the number of motor steps within the current LECP Major Frame.  Turn arounds in Sectors 8 and 1 or 2 are considered to be two steps. If = -1, datum is unknown.

20

18

LATEMP

I*2

LECP Log. Amp. Temperature-contains the log. amp. temp. (degrees C) x 128. LATEMP= -9999 if the temperature is unknown

21

19

TTEMP

I*2

LECP Telescope Temperature-contains the telescope temperature (degrees C) x 128. TTEMP= -9999 if the temperature is unknown

22

20

BAI

I*2

Basic Accumulation Interval-contains the number of milliseconds of accumulation times for the group 1 and 2 logics (Exception—for CR5A units are 0,01 sec.!!)

23

21

NG

I*2

Number of Groups-indicates the number of rate groups included in the current major frame

24

22

MRT/MPT

I*2

01=Master Rate Record, 02=Master Pulse Record, 4 SEDR, 10 ENG, 11 Cal

25

23

VN

I*2

Version Number-indicates the version of S1P used to process the current data

26

24

LEPT/LEMPA

I*2

Indicates data type in record: -1=Don't know; 0=LEPT; 1=LEMPA "Normal" NE Logics in GS3

27

25

RED A/B

I*2

Redundancy A or B logic flag, -1 Unknown, 0 = A; 1 = B

28

26

PROC. STAT

I*2

Check SW4 for 50/50.  If 50/50 then Item 26 0=LEPT Norm F.E. 1=LEMPA

Also check DQW 14-15=11 (in CR5A 0 = S1P; 1=S2P)

29

27

STEPPING RATE

I*2

Motor period in seconds: -1 = Unknown; 0 = not decoded; 9000 = encounter stow (V2 Jupiter) 10000 Stowed or commanded to position; otherwise one of 5,6,24,48,192,360 or 384 sec.

30

28

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

31

30

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

32

31

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

33

32

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

34

33

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

35

34

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

36

35

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

37

36

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

38

37

 

I*2

Status Word 5 (Near Encounter only) otherwise unused.

39

38

 

I*2

Spare

 

 

Return to MRT main page.

Return to Data File Descriptions main page. 

Return to Voyager LECP Data Analysis Handbook Table of Contents.
Return to Fundamental Technologies Home Page.


Updated 8/9/19, Cameron Crane

VOYAGER 1 ELAPSED TIME

--:--:--:--
Days: Hours: Minutes: Seconds

*Since official launch
September 5, 1977, 12:56:00:00 UTC

VOYAGER 2 ELAPSED TIME

--:--:--:--
Days: Hours: Minutes: Seconds

*Since official launch
August 20, 1977, 14:29:00:00 UTC

QUICK FACTS

Manufacturer: Voyagers 1 and 2 were built in the Jet Propulsion Laboratory in Southern California.

Mission Duration: 40+ years have elapsed for both Voyager 1 and Voyager 2 (both are ongoing).

Destination: Their original destinations were Saturn and Jupiter. Their current destination is interstellar space.