Minutes from the October 27, 2004 GBIPG
Spin DF / WJ
VHF DF System
DirecWay coordination on Allegheny Mountain
Powerkut ballasts for the
GB Public Library
Chamber EEseal filters
10. Jansky Lab shielded rooms
11. Josler Video Cameras
equipment and calibration
II software demo
Attendees: J. Acree (via phone),
R. Fisher, J. Ford, F.
Ghigo, W. Sizemore, D. Wirt
of this meeting was to document the status of various projects and
completion requirements with input from Jeff, who recently returned to
Summaries – Positive feedback has been received from observers using
spectrum summaries that have been developed. The
PF1-450 summary seems to be the preferred format. Jeff
recommended we continue to develop
Spin DF / WJ VHF DF System – The IPG received a Watkins-Johnson VHF DF
in “trade” for our labor investment of refurbishing PMFR Spin DF system. Wes will request assistance from Bud Berryman
of NSGA, Sugar Grove, to refurbish the antenna array and check the
system out. Manuals should arrive soon
- IPG position
paper – Awaiting approval from Phil
Jewell, Director, NRAO-GB.
coordination on Allegheny
Richard Laska (customer) has received the
second required cable
from us, but has not yet installed it. Upon
installation, Laska is to contact Wesley
install the cable ends. At that point,
the DirecWay installer can be scheduled. An additional coordination is underway for
Charlie Myers so he can have broadband access and the ability to work
home. It is hoped that the antenna
pattern, once received from Hughes, will be sufficient to verify the
installation will meet the ERPd limit.
ballasts for GB Library – Ballasts have been received.
Works area (Rusty) will install these as
their schedule permits. Mike Holstine approved the Works area performing work
at the GB
Filtering – The compact fluorescent fixtures are the worst offenders. Carla has designed a shielded enclosure for
the ballasts of the C3 fixtures and filters
are on order. The Works area will
systematically remove the fixtures and take to the shop for retrofit. Then, Wes or Chuck can install the filters
and return to the Works area to reinstall. Wes
will take the Carla’s drawings to John. A similar effort will
follow for the other style compact fluorescent fixture. HVAC
filter replacement is another outstanding item in the NSC.
Bad filters have been removed and are
“bypassed”. Jeff has identified (and
purchased?) a more robust filter that is not as susceptible to
damage by over tightening. Some
filtering effectiveness may be sacrificed, though.
Reduced NSC winter hours may provide a convenient
time for this work
- Anechoic Chamber EEseal filters – Filters have been ordered;
allow use of the indoor antenna test range without having to disconnect
cables. Gary Anderson can perform the
model verification – Gary Brown, Virginia Tech, has sent an
to Tom Gergely, NSF regarding this hopeful
effort. Tom will consider our suggested
proposal and provide direction to Gary
as to the best approach for funding. Jeff
that an initial measurements survey could be carried out jointly
between DoD and
NRAO-GB, regardless of any
NSF or Virginia Tech involvement.
surveys - Jeff mentioned that someone will need to pick up the
of working closely with astronomers in support of RFI surveys.
- Jansky Lab shielded rooms – It needs to be
whether or not the Flectron installation
around the shielded windows. Wes and
John will investigate whether the copper tape is curling which might
the Flectron to finish off the window.
Video Cameras – Cameras are located in the Janky
NSC and dormitory(?). Jeff
and Rick Reefer of Josler
an RFI mitigation solution of using a fine mesh placed over the domes
filtering the dc leads before exit. The
camera will need to be disassembled and taken to the shop for bead
blasting and chromating the inside. The next step is to install the mesh, bolt in
place and seal around filters and barrel connector with copper wool. Jeff believes this fix is good for the
Jansky Lab distances and beyond, but not
closer to the
GBT. Jeff also suggested purchasing RF
gasket material to replace the braided shield being used in the
call outs – The new contact person is Wesley Sizemore (ext. 2144 or
- Navy equipment and
calibration – Jeff will try to assist us in the future with equipment
calibration and equipment for propagation model validation.
- OASIS II software demo - Wesley
and Denise viewed a
very impressive demo of the OASIS II spectrum monitoring software,
which is a
computer interface that drives up to four instruments including
spectrum analyzers. The FCC monitoring
station recently purchased this software and it looks very promising to
our monitoring station capabilities. Wesley
will arrange another demo.
- Cognitive radio seminar –
Jeff attended a seminar in D.C. on cognitive radio.
Any persons interested in hearing more about
it may contact Jeff directly.