Summary of 2014 SARA Western Conference ~ Bishop, California Julian Jove

Summary of 2014 SARA Western Conference ~ Bishop, California

Julian Jove

The 2014 SARA Western Conference was held in Bishop, California USA over the weekend of 22~23 March at the Owens Valley Radio Observatory (OVRO) and Holiday Inn Express. Bill and Melinda Lord again worked hard to get everything setup, and David Westman helped arrange our visit to the OVRO, which is about 27 road miles south of Bishop . Whitham Reeve, conference coordinator, did very little but, of course, took all the credit as we have come to expect. We had 30± attendees at this year’s conference, and to my knowledge there were no trouble-makers in the group except, as usual, SARA president Bill Lord.

The format for this conference included presentations by SARA members and outside speakers and tours of the radio telescopes and laboratory facilities and shops at the main OVRO site in Owens Valley and the CARMA (Combined Array for Research in Millimeter-Wave Astronomy) site in the mountains east of OVRO. Our morning session on Saturday was at Building 12 on the main site and included opening remarks by the president, an introductory astronomy presentation by SARA member and director Tom Hagen, and presentations by two speakers from OVRO, Stephen Muchovej and David Hawkins. We then toured the aforementioned sites with Mark Hodges (Design Engineer) leading us for the OVRO tour and Nikolaus Volgenau (Assistant Director of Operations) leading our tour of CARMA about 15 road miles from OVRO.

Pictured: Left-to-right, Front: Tom Hagen, Eric Minassian, Stephen Muchovej, Ken Redcap, Scotty Butler, Jerry Espada, Whitham Reeve. Next row: Virginia Weisz, Karoline Abedi, Ray Fobes, Robert Tucker, Karen Nelson, Lorraine Rumley, Stuart Rumley, Lynne Gose, Jeff Gose, Karin Arnold, Fred Miles, Wolfgang Arnold. Back row: Bill Lord, Mark Hodges, Jim Moravec, Keith Weisz, Richard Rynne, Nikolaus Volgenau, David Hawkins, Tom Butler, Curt Kinghorn, Stan Nelson, Keith Payea, John Roberts, JR Van Hise. Not pictured: Melinda Lord

We finished our tours of the OVRO and CARMA sites early Saturday evening and had our group dinner at Astorga’s Mexican Restaurant just outside Bishop on the North Sierra Highway (Highway 395). Astorga’s is the only restaurant in town that could accommodate 30 people in one group on Saturday night. This worked out quite well. We ate no end of chips and salsa and then had various Mexican dishes and drinks. Another restaurant we found in Bishop that has great food and drink is the Back Alley – the restaurant in the local bowling alley. The service there was excellent, and it actually is in the back alley behind our hotels.

We continued our conference on Sunday morning in the “conference room” at the Holiday Inn Express in downtown Bishop, across the street from SARA’s official hotel the Creekside Inn. The management of this Holiday Inn Express must have been on vacation. On our arrival we were told by the front desk “nobody left us a note or anything about this”. Melinda Lord, SARA Treasurer, had previously made arrangements for the conference room but it was not setup for us and nobody there knew we were coming. Furthermore, it was much smaller than we were led to believe. It had three or four chairs, a table and a projection screen. Melinda quickly took charge and grabbed a wrecking bar and industrial size reciprocating saw. In no time we robbed the hotel’s dining area and every loose chair we could find and by 9:00 AM had 30 chairs setup in the room. One of the hotel’s maintenance staff was very helpful, but he was the only one in the whole Holiday Inn Express Empire who could not care less about our previous arrangements. As it turned out we made out okay and we were treated to numerous technical presentations by SARA members and directors (see the schedule of presentations and their abstracts at the end of this report). Wolfgang Arnold manned the air conditioning controls – we needed the refrigeration unit to cool the room with 30 people that was designed for 10.

Satellite Images of the Sites

Owens Valley is approximately 250 miles north of Los Angeles on the east side of the Sierra Nevada Mountains not far from nowhere. The image below is for 30 km altitude and shows the city of Bishop in upper-left, the main OVRO site in lower-middle and the CARMA site at middle-right. A scale bar is in the lower-left. The main site is about 11 airline miles to the south and east of Bishop but the drive is closer to 27 miles. See satellite image from 3 km altitude below. The CARMA site is another 9 airline miles from OVRO but requires driving about 15 miles into the mountains on a narrow, wandering road. A satellite image from 3 km altitude also is shown below.

Photo Tour of Owens Valley Radio Observatory

 

Above: Building 12 on the OVRO site where we had presentations on Saturday morning in a comfortable conference room. The building is conveniently located near the 40 m radio telescope shown below.

 

 

 

 

Schedule for SARA Western Regional Conference ~

22~23 March 2014

As-of 1 March 2014 ~ Subject to change

Day 1: Saturday, 22 March

Morning session at conference room at OVRO followed by a catered lunch at OVRO

Afternoon tours of the OVRO and CARMA facilities by Mark Hodges and Nikolaus Volgenau

Day 2: Sunday, 23 March

Morning session at conference room at Holiday Inn Express (in Bishop)

Afternoon session at conference room at Holiday Inn Express

Saturday, 22 March

               8:00 AM                Registration & hosted breakfast bar open

               9:00 AM                Welcome by SARA President Bill Lord

               9:15 AM                Tom Hagen, Introduction to Amateur Radio Astronomy

             10:00 AM                Stephen Muchovej, Cosmology Observations at OVRO

             10:45 AM                Break

             11:15 AM                David Hawkins, Digital Processing for Radio Astronomy

             12:00 PM                Hosted lunch

                1:30 PM                |

                      |                        | Tour of Owens Valley Radio Observatory hosted by Mark Hodges

                      |                        | and tour of CARMA facility hosted by Nikolaus Volgenau

                5:00 PM                |

                6:30 PM                No host dinner at Astorga’s Mexican Restaurant in Bishop

Sunday, 23 March

               7:30 AM                Hosted breakfast bar open

               9:00 AM                Stan Nelson, Meteor Forward Scatter Logging Activities

               9:45 AM                Tom Hagen, Measuring the Field Strengths of VLF Stations

             10:30 AM                Break

             11:00 AM                Ken Redcap, An Off-The-Shelf 611 MHz Total Power Radio Telescope

             12:00 PM                Hosted lunch

                1:30 PM                Keith Payea, Characterizing and Stabilizing a Radio Jove Receiver for 24/7 Remote Operation

                2:15 PM                Whitham D. Reeve, Noise and Noise Figure Measurements Tutorial

                3:00 PM                Break

                3:30 PM                Curt Kinghorn, Transforming an Itty-Bitty into a Serious Radio Telescope by putting it on "Steroids”

                4:15 PM                Open discussion

                5:30 PM                Closing remarks

Abstracts next page

Abstracts ~ SARA 2014 Western Regional Conference

22 ~ 23 March 2014

Introduction to Amateur Radio Astronomy, Tom Hagen. Amateurs have a number of opportunities to pursue radio astronomy as a hobby in the Hz to GHz frequency range. At the lowest frequencies, radio frequency (RF) energy in the audio frequency range (wavelengths of hundreds of miles) can be detected with a natural radio receiver comprising a whip antenna and a high input impedance audio amplifier. At higher frequencies, ionospheric solar disturbance monitoring may be done with a computer sound card and a simple pre-amplifier in the 15-48 kHz range.  Radiated disturbances from the planet Jupiter can be heard on shortwave receivers around 20 MHz.  Other bands centered on 38, 408, and 611 MHz are available too.  One of the most important bands is the 21 cm neutral hydrogen HI emission line at 1.42 GHz.  Many amateurs use re-purposed C-band satellite dishes to make observations and even complete RF contour maps of the sky at this wavelength.  Finally, a surplus Ku band TV satellite dish (Dish Net or Direct TV dish) can be made into an “Itty Bitty Telescope” (IBT) to demonstrate the principles of thermal emission from bodies at room temperature, such as trees, cars, humans, and so on at the operating frequency of around 12 GHz.  And last if not least, SARA members get the opportunity to use a 40 foot diameter dish at Green Bank, WV, to do observations on 21 cm!

Cosmology Observations at OVRO, Stephen Muchovej. In less than a century we have advanced from knowing almost nothing about the Universe as a whole to measuring it with exquisite precision. This revolution in our understanding is made possible through the discovery and precise measurements of the Cosmic Microwave Background (CMB), the relic light left over from the Big Bang. Scientists have been active in the study of the CMB since the 1980s. Whereas first efforts focused on CMB detections, these have evolved into precise measurements of its anisotropy and secondary effects, both of which inform us about the nature of the Universe and its expansion. In his talk, Dr. Muchovej will present an overview of cosmological studies undertaken at OVRO, from the initial measurements of the CMB to the latest efforts in mapping the so‐called “Dark Age” of the Universe. 

Digital Processing for Radio Astronomy, David Hawkins. Radio astronomy signal processing is increasingly performed using digital techniques. Digital signal processing is “imperfect,” but its imperfections are well understood (quantization and aliasing). Digital hardware allows the creation of systems containing many copies of digital processing subsystems, each with identical performance; something that is more difficult to achieve with analog subsystems. The real‐world is still analog, so analog‐to‐digital converters are required to convert to the digital domain as soon as it becomes feasible. Dr. Hawkins will review the 20GHz clock frequency analog‐to‐digital converters and the field programmable gate array (FPGA)‐based digital signal processing being used in CARMA’s next generation correlator systems. The technology details are similar to those used in “software defined radio,” so will be familiar to the SARA audience. The presentation will include slides, and a hardware “show and tell.”

Radio Meteor Detection in Roswell, New Mexico, Stanley A. Nelson. This paper and Power Point presentation describes the author’s twenty year involvement in radio forward scatter meteor detection and logging.  He will begin with a brief history of meteor detection by radio beginning in the 1940s. The forward scatter concept and practical amateur techniques to detect the occurrence of meteors will be outlined. He will note the various frequencies used with the challenge to adapt to the changes in the available carrier frequencies used for meteor monitoring. They include services like SNOTEL, CW Radar via AFSSS (originally NAVSPASUR), WWV signals, and the loss of analog TV and the opportunities using digital TV carriers. Also, the collaboration with SpaceWeatherRadio.com and Dr. Tony Philips will be highlighted and our on-going involvement providing the public the opportunity to listen to live meteor activity via the web.

Measuring the Field Strengths of VLF Stations, Tom Hagen. This presentation is about an attempt to get calibrated measurements of the magnetic field strengths of the various VLF stations used by the SuperSID program as reference sources to detect sudden ionospheric disturbances (SID’s). Presently, data coming in from the various SuperSID stations around the world is uncalibrated in amplitude.  When a SID is detected, there is a measurable change in relative signal strength, but actual field strengths are unknown.  Different stations around the world report different SID levels for a given event.  Are the causes of these differences loop antennas, preamp gains, sound card settings, sound card gain, or actual differences in field strength levels? And from a system design standpoint, the range of field strengths typically encountered would be good to know for improving and standardizing the design of pre-amps and loop antennas.

An Off-The-Shelf 611 MHz Total Power Radio Telescope, Ken Redcap. In the US, TV Channel 37 (608 - 614 MHz) is allocated to radio astronomy. This project is a work in progress and is my first effort on a radio telescope to detect energy in this frequency range. The telescope is being set up at the McMath Hulbert Solar Observatory in Lake Angelus, MI (McMathHulbert.Org). All electronic components and antennas (2) required were purchased on Amazon except for the low noise amplifier. All freeware software components were derived from sites with various versions of SDR# like SDRSharp.Com. Inspiration for the project comes from Kurt Kinghorn's presentation at the 2013 SARA Western Conference on low cost radio telescopes using off- the-shelf TV receiver antennas and an article in the August, 2013 SARA Journal about a low cost HI receiver.

Characterizing and Stabilizing a Radio Jove Receiver for 24/7 remote operation, Keith Payea, AG6CI, SARA Member. This presentation covers a series of tests which were performed by the author to characterize the frequency stability of a Radio Jove receiver used at the Robert Ferguson Observatory for public outreach and education. Our casual observations were that the receiver drifted over the course of a few hours, but no hard data was available. Based on the results of the tests and the target environmental conditions a method for stabilizing the receiver was designed, built, and tested. The result is a frequency stable receiver which can be left unattended for long term continuous operation.

Noise and Noise Figure Measurements Tutorial, Whitham D. Reeve. With the exception of some solar radio bursts, the extraterrestrial emissions received on Earth’s surface are very weak. Noise may mask or corrupt these weak emissions and places a limit on the minimum detection capabilities of a radio telescope. An understanding of noise and its measurement will help minimize its effects. This presentation is a tutorial that describes the basic characteristics of noise including noise temperature and noise power and how noise is measured.

Transforming an Itty-Bitty into a Serious Radio Telescope by putting it on "Steroids”. Curt Kinghorn. The ubiquitous Ku Band satellite dish can be converted into an “Itty-Bitty,” a fun device that is very useful in demonstrating the fundamental principles of radio astronomy.  But, the Itty-Bitty lacks the discrimination and amplification power to be a serious radio telescope.  In this project, the Itty-Bitty is put on “steroids” and transformed into a serious radio astronomy instrument by replacing the Itty-Bitty’s RF/IF/Detector unit with a serious radio receiver and replacing the audible tuning indicator with an electronic strip recorder.  Issues related to converting the Itty-Bitty including aiming, “finding” the intermediate frequency (IF) coming from the dish’s LNB, system gain and powering the LNB will be discussed.  If you have a “spare” computer lying around, the entire telescope can be built for less than $500.