Notes for RD0406 NRV 040728 ====================================================================== SPECIAL NOTES ====================================================================== This is the 6th geodetic session recording at 1 Gbit/s in 2004. Only two stations participate in this session: Wettzell and Westford. The purpose of the session is to provide information on whether there are unmodeled effects that depend on elevation, and whether more low elevation observations are needed per unit time than are currently scheduled in regular sessions. The schedule samples low (3-25), medium (25-55), and high (55-85) elevations with minimal azimuth motion. By fixing the antenna and source positions and EOP only clocks and atmospheres will be estimated. The other effects are slowly varying and the goal is to see whether 20-minute intervals, as currently used in analysis, is sufficiently short for estimating elevation-dependent parameters. In addition, by deleting some fraction of the low elevation observations, the sensitivity to the number of low elevation observations can be evaluated. Stations must select Mark 5 in drudg Option 11 and record on Mark 5 modules. Due to the high data rate, this session will record on multiple disk modules. Please see the DISK MODULE CHANGES section below. This schedule was made with a minimum SNR of 50/40 at X/S. The achieved SNRs are shown in the SNR MINIMUM AND ACTUAL section below. Stations MUST RUN the giga-bit test procedures to ensure you are ready to observe. Please see the TESTING AND SETUP section below. The S-band frequency sequence is different from the standard one because the channels would otherwise overlap due to the 16 MHz channel bandwidths. Please see the RECORDING MODE section below. ====================================================================== SESSION INFO ====================================================================== Parameter values for experiment RD0406 Experiment description: R&D Scheduler: NRV Correlator: HAYSTACK Nominal start: 2004-224-18:00:00 Nominal end: 2004-225-18:00:00 Current yyyyddd: 2004224 (2004.61)( 13229 MJD, WED. 11AUG.) Greenwich sidereal time: 15:22: 8.00 (18: 0: 0 UT) Sun's RA and DEC: 9h 27.2m 15d .3 ====================================================================== STATIONS ====================================================================== ID STATION Band SEFD Band SEFD DAT name ID Rack Recorder E Wf WESTFORD X 1500. S 1400. WESTFORD 07 Mark4 Mark4 V Wz WETTZELL X 750. S 1115. WETTZELL 33 Mark4 Mark4 ====================================================================== OBSERVATION SUMMARY ====================================================================== Key: Wf=WESTFORD Wz=WETTZELL Wf Wz Avg % obs. time: 41 41 41 % cal. time: 8 8 8 % slew time: 39 28 33 % idle time: 10 21 15 total # scans: 716 716 716 # scans/hour : 29 29 29 Avg scan (sec): 50 50 50 Total GB(M5): 4627 4627 4628 ====================================================================== RECORDING MODE ====================================================================== Recording mode setup for: WESTFORD WETTZELL Mode Tot.Rate Tot.BandW #chan #bits Barrel Mk341:2 1024.000 Mbits 512.000 MHz 14 2 NONE Chan.BW #Subpasses Tracks(*fan) Tot.tracks Speed 16.00 MHz 1 16(*2) 32 3.20 X-band spanned bw= 720.0 MHz rms spanned bw= 280.4 MHz S-band spanned bw= 125.0 MHz rms spanned bw= 50.7 MHz Effective number of channels recorded per sub-pass X S Total 19.780 11.868 32.000 Chan# Skyfreq BBC# 1 8212.99 1 2 8252.99 2 3 8352.99 3 4 8512.99 4 5 8732.99 5 6 8852.99 6 7 8912.99 7 8 8932.99 8 9 2227.99 9 10 2237.99 10 11 2257.99 11 12 2312.99 12 13 2347.99 13 14 2352.99 14 ====================================================================== SNR MINIMUM AND ACTUAL ====================================================================== Minimum SNR by baseline X-band (margin 0) S-band (margin 0) Wf Wf Wz 50 Wz 40 SNR histogram Distribution of X-band SNRs, for each baseline SNR: 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 >> Wf-Wz: 0 0 0 0 0 0 0 0 0 10 43 9 2 9 15 29 61 538 Total 0 0 0 0 0 0 0 0 0 10 43 9 2 9 15 29 61 538 Total number of obs: 716 Average SNR: 136.4 Median SNR bin: 90 Distribution of S-band SNRs, for each baseline SNR: 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 >> Wf-Wz: 0 0 0 0 0 0 0 0 266 57 86 113 61 13 4 13 7 96 Total 0 0 0 0 0 0 0 0 266 57 86 113 61 13 4 13 7 96 Total number of obs: 716 Average SNR: 58.2 Median SNR bin: 55 ====================================================================== TESTING AND SETUP ====================================================================== This session requires 4 ribbon cables between the Formatter and the Mark 5 Recorder. If one of these cables is missing, the correlator will not be able to read any of the data. Mark 4 stations must run ftp://web.haystack.edu/pub/mark5/SNAP/chk1024.snp with ftp://web.haystack.edu/pub/mark5/SNAP/chk1024.prc Send a copy of the log to dsmythe@haystack.mit.edu, or put a copy in the misc directory on cddisa, with a follow-up e-mail to dsmythe. DO NOT TOUCH any of the cables between the Formatter and the Mark 5 recorder after this test has been run without any errors. ====================================================================== DISK MODULE CHANGES ====================================================================== This session will require 3 or 4 disk modules, depending on the sizes that you have available at your station. DRUDG does not know the sizes, so it shows an ever-increasing GByte count. Please be aware that you will have to change modules several times during this session, and plan accordingly. There are several things to consider: 1) Mark module change times. Select the modules you will use for this session, note their sizes, and then mark by hand the places in the schedule where a module change will be necessary, and which bank will need to be changed. You can use the drudg Option 5 listing for this purpose. 2) Change modules promptly. When a module is full, the FS will automatically switch to the next one and put up a notice that you should change the old one. It is good practice to change the module as soon as it's called for, because then you are ready to record on the new one. 3) Create prompt window. The notice to change the disk module will scroll off the screen pretty quickly and you might miss it. It is possible, using the fs.prompt program, to create a prompt window on the screen with a message that you should replace the module. The window will stay there until you dismiss it by clicking on "continue". It is possible to do this so that the schedule will not be blocked while the window is displayed. To do this, edit your "change_pack" procedure and insert the following line as the first line: sy=fs.prompt "change disk module that is not selected" & The use of the "&" at the end is of the line is crucial to making sure that the schedule is not blocked. Please make sure you enter the line exactly as shown (you can adjust the message inside the quotes). One thing to be aware of is that the prompt will not tell you which module to change, so you must be careful to select the right one, i.e., the one that is not currently selected. If you have any questions, please contact Ed Himwich (weh@ivscc.gsfc.nasa.gov).