RadioAstron Track, gt05

Yarragadee 12m

Observer: Arwin


  • 01:00:00 - 01:42:14 UT: 20V, no attenuation
  • 01:42:14 - 02:10:51 UT: 14V, 56 dB attenuation
  • 02:10:51 - 02:16:11 UT: 20V, 56 dB attenuation
  • 02:16:11 - 02:20:00 UT: 12V, 56 dB attenuation

Power and attenuation levels in the DBBC

  • RCP: DBBC RCP power and attenuation
  • LCP: DBBC RCP power and attenuation


  • 0100UT Experiment started OK. Checked with the prc file which loaded rfpic=cross,direct when schedule=gt05yg,#1 was entered. Recording for sband=direct(20v) from 0100 UT onwards. ifa power levels were very high, ifa was approx 39000 whilst ifb was around 29000. See Image 1 below
  • 0142UT Entered rfpic=*,cross. Recording for Sband=cross from 12:42UT onwards. The power levels were under control for this setting, ifa settled around 24800 whilst ifb settled around 29000. See Image 2 below
  • 0149UT Noticed the proc file had a comment on the line indicating the switch state. The line read “rpfic=cross,direct and as such may not have loaded the correct setting and just imported the default rfpic=direct,direct?
  • 0150UT Manually entered rfpic=cross,cross and started recording for the sband=cross (14V) again. Power levels were stable and near the target power levels (ifa and ifb). See Image 3 below
  • 0210UT Entered rfpic=cross,direct to record again for the s=direct 20v with the correct settings.
  • 0215UT Had asked the yg staff to lower the voltage to 12v at 0215UT. Entered rfpic=cross,cross again to observe at lower voltage because the peak was high in the spectrum analyser. Noticed a small drop followed by a big drop (Image:4) around 0218UT (not sure if this was related to the voltage setting or due to the spacecraft going out of view of the dish). The lower power level remained stable until 0220UT before the peak disappeared.
  • 0222UT Entered rfpic=direct,direct to return to the normal ivs mode. Cancelled the iread command output every 10 sec, fs terminated, tracking stopped, antenna stowed, UTC1-UTC time difference brought back to 0.