COVER INFORMATION Station: VLBA_PT (Code Pt ) Experiment: bb191c, 6cm HSA, Barvainis, Ulvestad et al. Exp. Code: bb191c Schedule Version: 1.00 Processed by SCHED version: 6.02 July 2005 PI: J.S. Ulvestad Address: NRAO, P.O. Box O Socorro, NM 87801 USA Phone: +1-505-835-7300 EMAIL: julvesta@nrao.edu Fax: +1-505-835-7320 Phone during observation: +1-505-835-7300 Observing mode: 256-8-2 Notes: HSA with Eb,Ar,GBT,Y27, 256 Mbps allocated Scheduled in 22-minute blocks for Ar and Eb Ar has long azimuth slew near transit Schedule for VLBA_PT (Code Pt ) Page 2 bb191c, 6cm HSA, Barvainis, Ulvestad et al. UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Mon 30 Jan 2006 Day 30 --- Next scan frequencies: 4971.49 4971.49 4979.49 4979.49 4987.49 4987.49 4995.49 4995.49 Next BBC frequencies: 871.49 871.49 879.49 879.49 887.49 887.49 895.49 895.49 Next scan bandwidths: 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 07 45 00 J1224+2122 09 10 10 45.4 93.7 -3.3 -62.3 0 1 1 0 07 45 00 07 47 00 =1222+216 09 12 10 45.8 94.0 -3.2 -62.2 120 F 1 1600 07 45 08 07 47 00 J1225+2235 09 12 10 46.3 92.4 -3.2 -63.3 -7 1 1 1600 07 47 00 07 48 50 --- 09 14 00 46.6 92.7 -3.2 -63.3 103 F 1 3067 07 47 00 07 48 50 J1224+2122 09 14 00 46.2 94.3 -3.2 -62.2 -7 1 1 3067 07 48 50 07 50 00 =1222+216 09 15 10 46.5 94.5 -3.2 -62.2 63 F 1 4000 07 48 50 07 50 00 J1225+2235 09 15 10 46.9 92.8 -3.2 -63.3 -7 1 1 4000 07 50 00 07 51 50 --- 09 17 01 47.3 93.1 -3.1 -63.3 103 F 1 5467 07 50 00 07 51 50 J1224+2122 09 17 01 46.8 94.8 -3.1 -62.1 -7 1 1 5467 07 51 50 07 53 00 =1222+216 09 18 11 47.1 95.0 -3.1 -62.1 63 F 1 6400 07 51 50 07 53 00 J1225+2235 09 18 11 47.5 93.3 -3.1 -63.3 -7 1 1 6400 07 53 00 07 54 50 --- 09 20 01 47.9 93.6 -3.1 -63.2 103 F 1 7867 07 53 00 07 54 50 J1224+2122 09 20 01 47.4 95.3 -3.1 -62.0 -7 1 1 7867 07 54 50 07 56 00 =1222+216 09 21 11 47.7 95.4 -3.1 -62.0 63 F 1 8800 07 54 50 07 56 00 J1225+2235 09 21 11 48.1 93.8 -3.1 -63.2 -7 1 1 8800 07 56 00 07 57 50 --- 09 23 02 48.5 94.0 -3.0 -63.2 103 F 1 10267 07 56 00 07 57 50 J1224+2122 09 23 02 48.1 95.7 -3.0 -61.9 -7 1 1 10267 07 57 50 07 59 00 =1222+216 09 24 12 48.3 95.9 -3.0 -61.9 63 F 1 11200 07 57 50 07 59 00 J1225+2235 09 24 12 48.8 94.2 -3.0 -63.1 -7 1 1 11200 07 59 00 08 00 50 --- 09 26 02 49.1 94.5 -3.0 -63.1 103 F 1 12667 07 59 00 08 00 50 J1224+2122 09 26 02 48.7 96.2 -3.0 -61.8 -7 1 1 12667 08 00 50 08 02 00 =1222+216 09 27 12 48.9 96.4 -3.0 -61.8 63 F 1 13600 08 00 50 08 02 00 J1225+2235 09 27 12 49.4 94.7 -3.0 -63.1 -7 1 1 13600 08 02 00 08 03 50 --- 09 29 03 49.7 95.0 -2.9 -63.0 103 F 1 15067 08 02 00 Schedule for VLBA_PT (Code Pt ) Page 3 bb191c, 6cm HSA, Barvainis, Ulvestad et al. UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Mon 30 Jan 2006 Day 30 --- 08 03 50 J1224+2122 09 29 03 49.3 96.7 -2.9 -61.7 -7 1 1 15067 08 03 50 08 05 00 =1222+216 09 30 13 49.5 96.9 -2.9 -61.7 63 F 1 16000 08 03 50 08 05 00 J1225+2235 09 30 13 50.0 95.2 -2.9 -63.0 -7 1 1 16000 08 05 00 08 07 00 --- 09 32 13 50.4 95.5 -2.9 -62.9 113 F 1 17600 08 05 00 08 08 00 J1224+2122 09 33 13 50.2 97.5 -2.9 -61.6 53 1 2 17600 08 08 00 08 09 00 =1222+216 09 34 13 50.4 97.6 -2.9 -61.5 60 R 1 16800 08 08 08 08 09 00 J1225+2235 09 34 13 50.8 95.9 -2.9 -62.8 -7 1 2 16800 08 09 00 08 11 00 --- 09 36 14 51.2 96.2 -2.8 -62.8 113 R 1 15200 08 09 00 08 11 00 J1224+2122 09 36 14 50.8 98.0 -2.8 -61.4 -7 1 2 15200 08 11 00 08 12 20 =1222+216 09 37 34 51.0 98.2 -2.8 -61.4 73 R 1 14133 08 11 00 08 15 20 J1310+3220 09 40 35 46.5 77.2 -3.5 -72.4 160 1 2 14133 08 15 20 08 22 00 =1308+326 09 47 16 47.9 77.9 -3.4 -72.9 400 R 1 8800 08 15 28 08 24 00 J1224+2122 09 49 16 53.4 100.4 -2.6 -60.7 99 1 2 8800 08 24 00 08 26 30 =1222+216 09 51 46 53.9 100.9 -2.6 -60.6 150 R 1 6800 08 24 08 08 26 30 J1225+2235 09 51 46 54.4 98.9 -2.6 -62.1 -7 1 2 6800 08 26 30 08 28 40 --- 09 53 57 54.9 99.4 -2.5 -62.0 123 R 1 5067 08 26 30 08 28 40 J1224+2122 09 53 57 54.4 101.3 -2.5 -60.4 -7 1 2 5067 08 28 40 08 29 50 =1222+216 09 55 07 54.6 101.5 -2.5 -60.3 63 R 1 4133 08 28 40 08 29 50 J1225+2235 09 55 07 55.1 99.6 -2.5 -61.9 -7 1 2 4133 08 29 50 08 31 50 --- 09 57 07 55.5 100.0 -2.5 -61.8 113 R 1 2533 08 29 50 08 31 50 J1224+2122 09 57 07 55.0 101.9 -2.5 -60.2 -7 1 2 2533 08 31 50 08 33 00 =1222+216 09 58 17 55.3 102.2 -2.4 -60.1 63 R 1 1600 08 31 50 08 33 00 J1225+2235 09 58 17 55.7 100.2 -2.5 -61.7 -7 1 2 1600 08 33 00 08 35 00 --- 10 00 18 56.1 100.6 -2.4 -61.6 113 R 1 0 08 33 00 08 36 00 J1224+2122 10 01 18 55.9 102.8 -2.4 -59.9 53 1 3 0 08 36 00 08 37 10 =1222+216 10 02 28 56.1 103.0 -2.4 -59.8 70 F 1 933 08 36 08 08 37 10 J1225+2235 10 02 28 56.6 101.0 -2.4 -61.4 -7 1 3 933 08 37 10 08 39 30 --- 10 04 48 57.1 101.5 -2.3 -61.2 133 F 1 2800 08 37 10 Schedule for VLBA_PT (Code Pt ) Page 4 bb191c, 6cm HSA, Barvainis, Ulvestad et al. UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Mon 30 Jan 2006 Day 30 --- 08 39 30 J1224+2122 10 04 48 56.6 103.5 -2.3 -59.6 -7 1 3 2800 08 39 30 08 40 40 =1222+216 10 05 59 56.8 103.8 -2.3 -59.5 63 F 1 3733 08 39 30 08 40 40 J1225+2235 10 05 59 57.3 101.7 -2.3 -61.1 -7 1 3 3733 08 40 40 08 43 00 --- 10 08 19 57.8 102.2 -2.3 -61.0 133 F 1 5600 08 40 40 08 43 00 J1224+2122 10 08 19 57.3 104.3 -2.3 -59.3 -7 1 3 5600 08 43 00 08 44 10 =1222+216 10 09 29 57.5 104.5 -2.3 -59.2 63 F 1 6533 08 43 00 08 44 10 J1225+2235 10 09 29 58.0 102.5 -2.3 -60.9 -7 1 3 6533 08 44 10 08 46 30 --- 10 11 50 58.5 103.0 -2.2 -60.7 133 F 1 8400 08 44 10 08 46 30 J1224+2122 10 11 50 58.0 105.1 -2.2 -58.9 -7 1 3 8400 08 46 30 08 47 40 =1222+216 10 13 00 58.2 105.3 -2.2 -58.8 63 F 1 9333 08 46 30 08 47 40 J1225+2235 10 13 00 58.7 103.2 -2.2 -60.6 -7 1 3 9333 08 47 40 08 50 00 --- 10 15 20 59.2 103.7 -2.2 -60.3 133 F 1 11200 08 47 40 08 50 00 J1224+2122 10 15 20 58.7 105.9 -2.2 -58.6 -7 1 3 11200 08 50 00 08 51 10 =1222+216 10 16 30 58.9 106.1 -2.1 -58.4 63 F 1 12133 08 50 00 08 51 10 J1225+2235 10 16 30 59.4 104.0 -2.2 -60.2 -7 1 3 12133 08 51 10 08 53 30 --- 10 18 51 59.9 104.5 -2.1 -60.0 133 F 1 14000 08 51 10 08 53 30 J1224+2122 10 18 51 59.4 106.7 -2.1 -58.2 -7 1 3 14000 08 53 30 08 54 40 =1222+216 10 20 01 59.6 107.0 -2.1 -58.0 63 F 1 14933 08 53 30 08 54 40 J1225+2235 10 20 01 60.1 104.8 -2.1 -59.9 -7 1 3 14933 08 54 40 08 57 00 --- 10 22 21 60.6 105.3 -2.1 -59.6 133 F 1 16800 08 54 40 08 57 00 J1224+2122 10 22 21 60.1 107.6 -2.0 -57.7 -7 1 3 16800 08 57 00 08 58 00 =1222+216 10 23 22 60.3 107.8 -2.0 -57.6 53 F 1 17600 08 57 00 08 59 00 J1225+2235 10 24 22 61.0 105.8 -2.0 -59.4 53 1 4 17600 08 59 00 09 01 00 --- 10 26 22 61.4 106.3 -2.0 -59.1 120 R 1 16000 08 59 08 09 01 00 J1224+2122 10 26 22 60.9 108.6 -2.0 -57.2 -7 1 4 16000 09 01 00 09 02 10 =1222+216 10 27 32 61.1 108.9 -2.0 -57.1 63 R 1 15067 09 01 00 09 02 10 J1225+2235 10 27 32 61.6 106.6 -2.0 -59.0 -7 1 4 15067 09 02 10 09 04 10 --- 10 29 33 62.0 107.1 -1.9 -58.7 113 R 1 13467 09 02 10 Schedule for VLBA_PT (Code Pt ) Page 5 bb191c, 6cm HSA, Barvainis, Ulvestad et al. UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Mon 30 Jan 2006 Day 30 --- 09 04 10 J1224+2122 10 29 33 61.5 109.4 -1.9 -56.8 -8 1 4 13467 09 04 10 09 05 20 =1222+216 10 30 43 61.7 109.7 -1.9 -56.6 62 R 1 12533 09 04 10 09 05 20 J1225+2235 10 30 43 62.2 107.4 -1.9 -58.6 -8 1 4 12533 09 05 20 09 07 20 --- 10 32 43 62.6 107.9 -1.9 -58.3 112 R 1 10933 09 05 20 09 07 20 J1224+2122 10 32 43 62.1 110.3 -1.9 -56.3 -8 1 4 10933 09 07 20 09 08 30 =1222+216 10 33 53 62.3 110.6 -1.9 -56.1 62 R 1 10000 09 07 20 09 08 30 J1225+2235 10 33 53 62.9 108.3 -1.9 -58.2 -8 1 4 10000 09 08 30 09 10 30 --- 10 35 54 63.3 108.8 -1.8 -57.9 112 R 1 8400 09 08 30 09 10 30 J1224+2122 10 35 54 62.7 111.2 -1.8 -55.8 -8 1 4 8400 09 10 30 09 11 40 =1222+216 10 37 04 62.9 111.5 -1.8 -55.6 62 R 1 7467 09 10 30 09 11 40 J1212+1925 10 37 04 64.0 118.8 -1.6 -50.1 -11 1 4 7467 09 11 40 09 13 40 =1210+197 10 39 04 64.3 119.5 -1.6 -49.7 109 R 1 5867 09 11 40 09 13 40 J1224+2122 10 39 04 63.3 112.1 -1.8 -55.3 -11 1 4 5867 09 13 40 09 14 50 =1222+216 10 40 14 63.5 112.4 -1.7 -55.1 59 R 1 4933 09 13 40 09 14 50 J1225+2235 10 40 14 64.1 110.0 -1.8 -57.2 -8 1 4 4933 09 14 50 09 16 50 --- 10 42 15 64.5 110.6 -1.7 -56.9 112 R 1 3333 09 14 50 09 16 50 J1224+2122 10 42 15 63.9 113.0 -1.7 -54.7 -8 1 4 3333 09 16 50 09 18 00 =1222+216 10 43 25 64.1 113.4 -1.7 -54.5 62 R 1 2400 09 16 50 09 18 00 J1225+2235 10 43 25 64.7 110.9 -1.7 -56.7 -8 1 4 2400 09 18 00 09 20 00 --- 10 45 25 65.1 111.5 -1.7 -56.3 112 R 1 800 09 18 00 09 20 00 J1224+2122 10 45 25 64.5 114.0 -1.7 -54.1 -8 1 4 800 09 20 00 09 21 00 =1222+216 10 46 25 64.7 114.4 -1.6 -53.9 52 R 1 0 09 20 00 09 22 00 J1225+2235 10 47 25 65.5 112.2 -1.6 -55.9 52 1 5 0 09 22 00 09 24 00 --- 10 49 26 65.9 112.8 -1.6 -55.6 120 F 1 1600 09 22 08 09 24 00 J1224+2122 10 49 26 65.3 115.3 -1.6 -53.3 -8 1 5 1600 09 24 00 09 25 10 =1222+216 10 50 36 65.5 115.7 -1.6 -53.0 62 F 1 2533 09 24 00 09 25 10 J1225+2235 10 50 36 66.1 113.2 -1.6 -55.3 -8 1 5 2533 09 25 10 09 27 20 --- 10 52 46 66.5 113.9 -1.6 -54.9 122 F 1 4267 09 25 10 Schedule for VLBA_PT (Code Pt ) Page 6 bb191c, 6cm HSA, Barvainis, Ulvestad et al. UP: D => Below limits; H => Below horizon mask. blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Tapes: Drive, Index, Start footage / Direction, Head Group, End footage. TPStart: Tape motion start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. Automatic tape allocation specified. Tape positions are just estimates. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Tapes TPStart Stop UT LST EL AZ HA UP ParA Dwell (see above) SYNC ---------------------------------------------------------------------------------------- --- Mon 30 Jan 2006 Day 30 --- 09 27 20 J1224+2122 10 52 46 65.9 116.5 -1.5 -52.6 -8 1 5 4267 09 27 20 09 28 30 =1222+216 10 53 57 66.1 116.9 -1.5 -52.3 62 F 1 5200 09 27 20 09 28 30 J1225+2235 10 53 57 66.7 114.3 -1.5 -54.6 -8 1 5 5200 09 28 30 09 30 40 --- 10 56 07 67.1 115.0 -1.5 -54.2 122 F 1 6933 09 28 30 09 30 40 J1224+2122 10 56 07 66.5 117.7 -1.5 -51.8 -8 1 5 6933 09 30 40 09 31 50 =1222+216 10 57 17 66.7 118.1 -1.5 -51.5 62 F 1 7867 09 30 40 09 31 50 J1225+2235 10 57 17 67.3 115.4 -1.5 -53.9 -8 1 5 7867 09 31 50 09 34 00 --- 10 59 27 67.8 116.2 -1.4 -53.4 122 F 1 9600 09 31 50 09 34 00 J1224+2122 10 59 27 67.1 118.9 -1.4 -50.9 -8 1 5 9600 09 34 00 09 35 10 =1222+216 11 00 38 67.3 119.3 -1.4 -50.6 62 F 1 10533 09 34 00 09 35 10 J1225+2235 11 00 38 68.0 116.6 -1.4 -53.1 -8 1 5 10533 09 35 10 09 37 20 --- 11 02 48 68.4 117.4 -1.4 -52.5 122 F 1 12267 09 35 10 09 37 20 J1224+2122 11 02 48 67.7 120.2 -1.4 -50.1 -8 1 5 12267 09 37 20 09 38 20 =1222+216 11 03 48 67.9 120.6 -1.4 -49.8 52 F 1 13067 09 37 20 09 40 20 J1310+3220 11 05 48 63.9 85.5 -2.1 -77.0 91 1 5 13067 09 40 20 09 45 00 =1308+326 11 10 29 64.9 86.0 -2.0 -77.2 280 F 1 16800 09 40 28 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. Setup file: /users/cwalker/sched/setups/v6cm-256-8-2.set Matches group v6cm_2 in /home/arana/cwalker/sched/catalogs/freq.dat Setup group: 10 Station: VLBA_PT Total bit rate: 256 Format: VLBA1:2 Bits per sample: 2 Sample rate: 16.000 Number of channels: 8 Passes/head pos: 1 Speedup factor: 1.00 Tape used at high density at 160.000 ips. Time per pass is 22.00 minutes. 1st LO= 4100.00 4100.00 4100.00 4100.00 4100.00 4100.00 4100.00 4100.00 Net SB= U U U U U U U U Pol. = RCP LCP RCP LCP RCP LCP RCP LCP BBC = 1 2 3 4 5 6 7 8 BBC SB= U U U U U U U U IF = A C A C A C A C VLBA FE= 6cm omit 6cm omit VLBA Synth= 15.4 4.1 15.4 The following frequency sets based on this setup were used. Frequency Set: 10 Setup file default. Used pcal sets: 1 LO sum= 4971.49 4971.49 4979.49 4979.49 4987.49 4987.49 4995.49 4995.49 BBC fr= 871.49 871.49 879.49 879.49 887.49 887.49 895.49 895.49 Bandwd= 8.000 8.000 8.000 8.000 8.000 8.000 8.000 8.000 The following pulse cal sets were used with this setup: Pulse cal detection set: 1 PCAL = 1MHZ PCALXB1= S1 S3 S5 S7 S1 S3 S5 S7 PCALXB2= S2 S4 S6 S8 S2 S4 S6 S8 PCALFR1= 510 510 510 510 6510 6510 6510 6510 PCALFR2= 510 510 510 510 6510 6510 6510 6510 Track assignments are: track1= 2, 10, 18, 26, 3, 11, 19, 27 barrel=roll_auto SOURCE LIST -- bb191c, 6cm HSA, Barvainis, Ulvestad et al. Catalog positions marked with *. Precession of date coordinates is based on stop time of first scan. Names used in schedule marked with *. Short names used in VLA and SNAP files marked with +. Observation date used in B1950/J2000 coordinate conversion (PRECDATE): 1979.900 No adjustments are made for rates (DRA, DDEC). Scan hours are for recording scans only. Baseline hours are only counted for scans above horizon at both ends. Source Source position (RA/Dec) Error (B1950) (J2000) (Date) (mas) * J1225+2235 12 22 56.587068 * 12 25 27.400900 12 25 46.684731 0.00 22 51 49.44291 * 22 35 13.05200 22 32 59.63062 0.00 From catalog imbedded in main SCHED input file. 0.964 scan hours, 76.059 baseline hours above horizon. * J1212+1925 12 10 23.542104 * 12 12 56.095713 12 13 15.605578 2.04 1210+197 19 42 27.70903 * 19 25 47.01652 19 23 34.50202 1.42 /users/cwalker/sched/catalogs/sources.vlba VLBA Calib Srcs - GSFC sols. - catalog 2004f_astro 0.033 scan hours, 2.304 baseline hours above horizon. * J1224+2122 12 22 23.408705 * 12 24 54.458390 12 25 13.754075 0.24 1222+216 21 39 23.03700 * 21 22 46.38861 21 20 33.26090 0.44 J1224+21 /users/cwalker/sched/catalogs/sources.vlba VLBA Calib Srcs - GSFC sols. - catalog 2004f_astro 0.631 scan hours, 44.348 baseline hours above horizon. * J1310+3220 13 08 07.560130 * 13 10 28.663849 13 10 46.668396 0.24 1308+326 32 36 40.23882 * 32 20 43.78289 32 18 30.52179 0.40 J1310+32 /users/cwalker/sched/catalogs/sources.vlba VLBA Calib Srcs - GSFC sols. - catalog 2004f_astro 0.189 scan hours, 16.568 baseline hours above horizon. * J1331+3030 13 28 49.657757 * 13 31 08.288049 13 31 25.816614 0.37 1328+307 30 45 58.64062 * 30 30 32.95926 30 28 22.89086 0.47 3C286 /users/cwalker/sched/catalogs/sources.vlba J1331+30 VLBA Calib Srcs - GSFC sols. - catalog 2004f_astro 0.000 scan hours, 0.000 baseline hours above horizon. The solar corona can cause unstable phases for sources too close to the Sun. SCHED provides warnings at individual scans for distances less than 10 degrees. The distance from the Sun to each source in this schedule is: Source Sun distance (deg) J1225+2235 129.6 J1212+1925 132.2 J1224+2122 129.6 J1310+3220 120.2 J1331+3030 115.7 Barry Clark estimates from predictions by Ketan Desai of IPM scattering sizes that the Sun will cause amplitude reductions on the longest VLBA baselines at a solar distance of 60deg F^(-0.6) where F is in GHz. For common VLBI bands, this is: 327 MHz 117. deg 610 MHz 81. deg 1.6 GHz 45. deg 2.3 GHz 36. deg 5.0 GHz 23. deg 8.4 GHz 17. deg 15.0 GHz 12. deg 22.0 GHz 9. deg 43.0 GHz 6. deg