Abstracts for 2016 SARA Conference

NRAO and Green Bank Overview; NRAO and SARA

Lory Mitchell Wingate

Abstract: The National Radio Astronomy Observatory (NRAO) enables forefront research into the Universe at radio wavelengths and operates a complementary, state-of-the-art suite of four radio telescope facilities and instrumentation for use by the scientific community, regardless of institutional or national affiliation, including: (a) the international Atacama Large Millimeter/submillimeter Array (ALMA) in Chile; (b) the Karl G. Jansky Very Large Array (VLA) in New Mexico; (c) the continent-spanning Very Long Baseline Array (VLBA); and (d) the 100-meter diameter Green Bank Telescope (GBT) in West Virginia. In partnership with the scientific community, the NRAO helps train the next generation of scientists and engineers and promotes astronomy to foster a more scientifically literate society. The NRAO also provides operational computing support to its user community, including access to high performance and high throughput computing. The NRAO is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The Green Bank facility is host to the SARA East Conference. This presentation will provide an overview of NRAO and the Green Bank site, as well as an introduction to the long-standing association between NRAO and the SARA organizations.

Lory Mitchell Wingate is the NRAO’s Director of the Program Management Department. She has over twenty-five years of experience in both for-profit and non-profit companies. Lory has an MBA in Information Technology Management, and is a Certified Project Management Professional (PMP®), and an INCOSE Expert Certified Systems Engineer. Lory’s area of expertise is in program management, project management, and systems engineering.


21 cm Adventures—Building Antennas and Using SDR's to Detect HI and Continuum at 1.42040571..... GHz

Tom Hagen

Abstract: I've been wanting to do 21 cm work with my own telescope ever since I've been a member of SARA starting in 2010. I got a taste of this wavelength on the 40' telescope at Green Bank when the late Dave Benham and I captured Cygnus X-1 and the galactic plane on our first stab at using the 40 footer, continuum mode. There's not much new work here, it's really just an account of all the effort a guy like me has to put forth to get 21 cm readings using typical amateur-sized antennas and the latest low cost receiving equipment and freeware processing software. I'll document a self-built horn antenna and a re-purposed C Band dish. Also covered will be the trials and tribulations of working with different software defined radios (SDR's) and post-processing software. The intent is to help new amateur radio astronomers (like me) jump in and get started on this most important wavelength.



Circuit Ground Concepts

Bruce Randall NT4RT

Abstract: Circuit ground is a common but often misunderstood concept. This paper will explain about circuit ground by showing and explaining cases where grounding has caused problems. Examples will include DC, audio frequency, RF and microwave grounding problems. Bypassing for power lines will also be discussed as this is making a power line effectively a ground for RF and audio purposes.
Ground loops will also be described.



Radio Astronomy and Girl Scouts – A Feminine Touch

Dr. J. Wayne McCain, Professor and Marguerite M. Murphey, Adjunct Professor

Abstract: Girl Scouts officially began over 100 years ago with one woman, Girl Scouts’ founder Juliette Gordon “Daisy” Low, who believed in the power of every girl. She organized the first Girl Scout troop on March 12, 1912, in Savannah, Georgia to primarily help girls discover their strengths, passions, and talents. Today, the organization, 2.7 million strong—1.9 million girls and 800,000 adults, continues the Girl Scout mission of building girls of courage, confidence, and character who make the world a better place. GS is also about empowering girls to reach their potential in all aspects of life through education and counseling. Over the years, significant contributions have been made by girls (who of course become women in our society) in the scientific arena, including radio astronomy. This paper describes one activity to introduce girl scouts to the field of astronomy in general and radio astronomy specifically in an effort excite their interest in the field and provide insight not normally emphasized in their sphere of influence. In cooperation with the newly formed Von Braun Astronomical Society’s Radio Astronomy Special Interest Group (RASIG), a special program was organized and presented to a group of GS ‘Daisies’ on Saturday, April 23rd. Results are presented along with data from pre and post survey’s administered during the activities.



Establishing a Radio Astronomy Special Interest Group (RASIG) within the VBAS

Dr. J. Wayne McCain, Professor and Steve Patrick, VP

Abstract: The Von Braun Astronomical Society (VBAS) was originally founded in 1954 as the Rocket City Astronomical Association, thanks to the efforts of a group of high school students interested in Astronomy along with the help and influence of Dr. Wernher von Braun. By 1956, the organization had grown to include several members of the Von Braun Missile Team and they completed the observatory. VBAS facilities today include a second observatory, astronomical library, solar telescope, and planetarium. During the past year (2015) and this spring, several VBAS members have shared radio astronomy information regarding the RASDR project begun under the auspices of the Society of Amateur Radio Astronomers (SARA) and several other projects (JOVE, SuperSID) with the VBAS. These presentations have resulted in the generation of significant interest in radio astronomy (RA) within the VBAS. This paper documents the rise of interest in radio observing within the organization and the formation of an official RA Special Interest Group. Initial efforts are documented including the development and implementation of SuperSID and Project JOVE observing stations with pictures and data from several sessions. Discussion regarding use of the RASIG as an educational outreach tool with Athens State University, the University of Alabama at Huntsville, and local Girl Scouts is also included.



Using New Signal Sources for Meteor Observations

Bascombe J. Wilson

Abstract: : Meteor observation using signals reflected from ionized meteor trails has traditionally been a good introduction to radio astronomy for students and amateurs and has provided a continuing source of useful data for advanced studies.
Most high-powered military signals disappeared at the end of the Cold War. Major U.S. and Canadian TV stations converted from analog transmissions to digital, with greatly reduced power levels on their carrier signal. On December 31, 2015, most of the remaining analog TV transmitters in Mexico went silent. While a few analog TV transmitters remain on the air, virtually all are scheduled for closure in the near future.
This presentation will compare the remaining signals in the useful frequency range as a basis for planning future receivers for meteor observation.
The Current Situation and What Will Change in the Next Three Years:
1. Analog to Digital TV Conversion
2. Military Radar
3. Low Band VHF Emissions
How to Make the Most of What’s Left:
1. Digital TV Carriers
2. Low Power U.S. Analog TV Transmitters
3. Canadian and Mexican Stations
4. FM Radio Transmitters – A Novel Approach from SARA Western Conference
5. Navigational Aids for Aviation
6. Amateur Radio VHF / UHF Beacons



Green Bank Forty Foot Telescope Update

Skip Crilly

Abstract: The Green Bank Forty Foot Telescope has been improved during the last two years, with the replacement of some older equipment and the provision of RF over fiber links from the feed to the receiver room. Changes will be described, together with receiver block diagrams, measurements, and system access for those who wish to attach their own receivers and back end processing.



Searching for ET in all the Wrong Places

Tom Crowley, Past SARA President

Abstract: We have searching for ET for well over 50 years. Why haven't we found them? Perhaps it's time to look at other methods available using the latest technologies to improve the search. A review of where we have been in the search and a look at many new techniques that may well prove there is life in our Galaxy in the near future. How new methods of finding planets in the Goldilocks zone around distant suns may improve the odds of finding SETI using the SETI Search. Astro-Biology methods in conjunction with candidate planets may be our best technique for finding life on other worlds.



My first dish

Preston Ozmar

Abstract: Recently I had the opportunity to install my first dish and radio telescope receiver for 21 cm.  The experience I gained will help me in the future and may help those who are planning to install their own dish.  I talk about the decisions that I made and the installation process.  Then some sample data is presented.



SARA Mobile Interferometer at NRAO Green Bank

Skip Crilly

Abstract:  This presentation will describe an amateur mobile radio interferometer under construction by SARA members at NRAO Green Bank. A maximum baseline of four hundred meters is expected to resolve separated objects to two arc minutes. The measurement system includes a six foot diameter reflector antenna placed on a diesel truck, providing one element of an interferometer, while the Forty Foot Telescope is the second element. The antenna truck will be driven along a variable baseline, while an Intel i7 cross-correlator captures signals in the receiver room, providing measurement points along the variable baseline. The initial objective is to measure the 1425 MHz separation angle of the Cygnus A radio lobes resulting from the jets emitted by the quasar's central black hole engine.



Radio Astronomy Software Defined Receiver S.W.O.T. Analysis

Don Eslinger, Tikia Allen, Megan K. Stroud, Dr. J. Wayne McCain

Abstract: The Radio Astronomy Software Defined Receiver (RASDR) is a state-of-the-art (SOTA), customized, UHF radio receiver that has been designed with the special features needed for radio astronomy applications in mind. The RASDR project, undertaken by a group of SARA volunteers, is now in the third design ‘spin’ that will result in what is hoped to be a very price-competitive and superior performance device unique in its utility and cost. Florida Institute of Technology (Florida Tech) students, under the guidance of Dr. J. Wayne McCain, have studied the RASDR project from engineering and project management perspectives since the summer of 2015 when a group of students developed a preliminary project management plan. Florida Tech’s involvement has continued with the latest student effort (ENM 5420, Technology Commercialization Strategies) resulting in a ‘Strengths, Weaknesses, Opportunities, and Threats’ (SWOT) analysis that compares the RASDR with other SDR receivers in the current marketplace. This paper summarizes these latest results and ranks RASDR with other devices based on utility, performance, price, and other factors.



RASDR Unbound: Moving toward RASDR4

Paul Oxley, David Fields, and Stan Kurtz

Abstract: We have obtained pre-production circuit boards for a high-performance SDR module, LimeSDR, and are testing it to see if using it as a core component of RASDR4 appears the best approach to providing a high-quality SDR for the SARA community.  Analyses and test results are presented.
The goal of the RASDR team is to support SARA members by developing and supporting a high-quality Software Defined Receiver for Radio Astronomy.  It should be available at reasonable cost, documented, and have high functionality to support member’s interests.  Well-tested RASDR2 and recently-designed RASDR3 use two high-density circuit boards. A wide-band analog front-end board using a single-chip (LMS6002D) transceiver is linked to a function control board that connects to a computer via a USB3 interface.  RASDRviewer software runs in a Windows environment and performs receiver control, FFT analysis, multi-frame averaging, power monitoring and other functions. RASDR2 is normally used with an antenna, filter, preamplifier, upconversion and external frequency/time reference signals, and it has been tested in several high-performance configurations.
The successor to the LMS6002D, the LMS7002M, is being produced commercially and the new chip offers dual-receiver and dual-transmitter functions, wider spectrum coverage (0.1-3200 MHz) and wider bandwidth.  The LMS7002M in LimeSDR configuration is a project seeking crowdfunding.  The LimeSDR offers a wide range of performance options and appears to be attractive from both a price and performance perspective as a component of RASDR4.