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1. Direct Observer Support:

• Researched and monitored the band 456-460 MHz in support of Jeremey Darling's projects. Also provided detail at frequencies of interest 443,458, and 473 MHz.

2. NRQZ (Zone 5) Administration:

• ERPd Restriction values amended PW 28MAR08

• Four site inspections were deemed unnecessary due to system design.

• Grand tour: Dr. Andrew Clegg, NSF

• Monitoring at 172.875 MHz (FAA transmitter on Apple Orchard Mountain)

• Located a digital paging transmitter in Marlinton on 462.875 MHz that was being monitoring in connection with Jeremy Darling's request concerning possible RFI near 458 MHz. Still deciding on how best to proceed.

3. WVRAZ:

• In a meeting including Richard P. and Andy Clegg, determined appropriate to use NRQZ limits for the WVRAZ.
• Continued monitoring for power line and cable TV RFI. Located 8 cable TV leaks that were repaired.
• Working with new legal representation on the Frontier Communications issue.
• Prepared materials for the Snowshoe Homeowner's Association Meeting; business manager and site director gave presentation and tour for the Snowshoe Homeowner's Association Meeting.
• Approved the use of a low power AM transmitter (530-1700 kHz band) at Cass Scenic Railroad.
• Investigated a report of possible RFI from Green Bank library. I spoke with Jane and she was told by "someone" that the wireless phone she used was generating RFI when not in use and that she should replace it with another brand. I explained that we were mostly concerned about the actual use of the phone and that it was indeed a source of RFI to the GBT when in use and ask if she could use a wired phone. She was very reluctant to give up her portable phone as she uses it daily and a wired phone would be a great inconvenience. She does not have a wired phone to use at this point. Mike Holstine stated that he would talk to her.
• Downloaded and successfully used 3 meter resolution topography data for the state of WV.

4. On-Site RFI Mitigation (Zones 1-2):

• Anechoic Chamber testing:
  • Trimble GPS for Don Backer
  • GBT Feed Defroster
  • 3.6m dish antenna drive motors (not complete)

5. RFI Policy, Instrumentation, Reporting Mechanism, etc:

• GBT Monitoring Station
  • Spectral monitoring shows that system is functional; initial results show that the DME antenna gives a better SNR than the DME signals coming in the sidelobes of the L-band receiver.
  • Rick has begun to modify the program that will add the AZ of the GBT to the AZ of the monitoring station antennas.
  • Sent Anritsu Spec An in RFI rack off for repair; power supply was replaced.
• RFI Database
  • Form Flow specifications created for the Known Sources and Contact History data entry forms and given to software division.
  • Summer student has completed IDL spectral display tool.
• Gathered specs on ferrite materials and organized ferrite stash in the instrument room.
• Received new ICOM R-9500 communications receiver from Sugar Grove. However, the unit provided was the cellular blocked version and was returned to ICOM for correct unit.
• Receiver new Radio Control driver for ICOM R-9500 for beta testing.
• New heating/cooling unit installed at 40' RFI trailer.
• High pass (>50 MHz) filter installed on omni antenna at 40' RFI monitoring station to prevent failure of first stage of the broadband amplifier that seems to be failing due to strong low frequency signals. Seems to be working.
• NSWC agreed to pay for the repair of a 100 MHz - 4.0 GHz amplifier that they had provided in connection with the propagation model verification project and was damaged by strong low frequency signals. CB??

6. Outreach:

• Gave RFI presentations/demonstration at the Single Dish Summer School.
• Gave Anechoic Chamber tours at the Single Dish Summer School.
• Wesley gave RFI presentations/demonstration to NASA teacher group.
• Wesley gave RFI presentations/demonstration to Governor's School of Math and Science. Also worked with smaller groups from the Governor's School.

7. Other:

• Attended Operations meetings
• Attended Project Management meetings
• Attended RFI/EPO meetings
• Attended NRAO Spectrum Managers Teleconference

-- PauletteWoody - 20 Aug 2007