November 7, 2019 Club Meeting
Thursday, November 7, 2019 at 7:00 PM Medford Police Department Community Room, 219 S. Ivy St., Medford, OR
Program: Tangerine SDR, Tom McDermott, N5EG
Tangerine SDR is a cooperative project between the HAMSCI amateur science project and TAPR (Tucson Amateur Packet Radio). TAPR is developing hardware for a science package to be used in ionospheric research that will be aided by the HAMSCI project. This is a citizen-science initiative to deploy numerous low-cost science packages in order to improve data collection for scientists to study ionospheric physics.
Recently this project was funded by a grant from the National Science Foundation. This instrument has been nicknamed the ‘Space Weather Station’. The Principle Investigators are from University of Scranton, and the Massachusetts Institute of Technology Haystack observatory.
The hardware is planned to consist of a dual-channel 0.1-30 Mhz SDR receiver, FPGA board for signal processing, a single board computer for control and local data storage, and a 3-axis magnetometer. Scientists will be able to trigger and capture data from these space weather stations over a wide geographic area, and store annotated data in central servers. The program will cover some key aspects of the hardware, and some project objectives.
Biography: Tom McDermott, N5EG is club newsletter editor. He is active in the system engineering and analysis of the Tangerine SDR equipment, and is designing the dual-channel receiver unit.
At the November meeting we need to nominate and elect the four officers for 2020. Three current office holders have agreed to run again for their respective offices (Treasurer, Secretary, and Vice President). At this point however we do not have anyone who has agreed to run for President.
Announced in the November 2019 issue of The Repeater.
Meeting Notes
From the December 2019 issue of The Repeater.
RVARC Nov. 7, 2019 Meeting Minutes
7:03pm Meeting called to order by Vice-President Scott Cummings, NA7OM. Attendance was 28 people.
Don Bennett, KG7BP, said that at the Oct. 26 license test 5 new Technicians and 2 new Generals were added to our number.
Allen Taylor, K7GT, reported on the October 5-6 California QSO Party where they gathered at Bob Welch’s QTH (W6AQU) near Montague, CA. With an SFI of 63, phone reception was poor, but with the CW crew alongside, around 98000 points were accumulated. The food & fuel bill came to $208, so Scott, NA7OM, made a motion for the club to approve the expense, Tom, N5EG, seconded, and the vote was a unanimous yes.
On the subject of club officer elections, Scott, NA7OM, John, KF7UMK, & Mike, WB6FFC, all agreed to run for VP, Secy. & Treasurer again. No one volunteered to run for President so that office is vacant. The volunteers were deemed elected by acclamation. We need a volunteer to stand for President, and help realize their visions for the future of the club.
The Treasurer reported a bank balance of $4714.00 plus $132.20 in petty cash, along with tonight’s six newly paid 2020 memberships. Club insurance has been paid, as well as the $150 donation to the ARRL Spectrum Defense Fund.
(Just a reminder that further info on amateur radio interests is available at www.arrl.org/news,including news like:
- 11/18/2019 | WRC-19 Grinds On Into Third Week
- 11/21/2019 | ARRL Self-Guided Emergency Communication Course EC-001-S is Now Available On Demand
- 11/25/2019 | ARRL to Oppose Proposal to Eliminate 3.3 – 3.5 GHz Amateur Allocation
- 11/26/2019 | WSJT-X Development Group Announces Second Bug-Fix Release, WSJT-X Version 2.1.2)
7:23pm Break for visiting and snacks.
7:55pm Main presentation on Tangerine SDR by Tom McDermott, N5EG.
Tonight’s talk is on the development of a new modular SDR by HAMSCI, TAPR, and others, in conjunction with HAMSCI’s Personal Space Weather Station project.
The lead HAMSCI organizer is Dr. Nathaniel Frissell, W2NAF, a professor at Scranton University (previously of the New Jersey Institute of Technology, Center for Solar-Terrestrial Research).
Tucson Amateur Packet Radio (TAPR) is designing and building the hardware.
The PSWS - Personal Space Weather Station is a set of specific TangerineSDR modules plus firmware, a 3-axis magnetometer, a local host computer + storage + software, and a central server (run by scientists) to collect and manage data.
For now the PSWS plan is:
- Two Low Cost HF (0.1 - 30 MHz) receivers with reasonable dynamic range.
- Up to 8 bands per receiver. NF <= 10 dB.
- Ability to calibrate receiver amplitude.
- Tight phase coherence between receiver channels
- Ability to do interferometry.
- High accuracy time-stamping of samples & high frequency accuracy. Objective: ±50 nanoseconds during normal GPS reception.
- 3-axis magnetic field measurements:
The TangerineSDR modules consist of:
- the Data Engine - FPGA based
- the RF Modules - a collection of receivers, transmitters, and transceivers.
- the Clock modules - a collection spanning low-cost to high-performance.
TangerineSDR target applications are:
- HamSCI Personal Space Weather Station (PSWS)
- Phase 4 Satellite Ground Station (P4G)
- Academic uses to teach SDR and FPGA techniques
- Amateur Communications SDR
- Experimenters’ (Amateur and non-Amateur) SDR
- Remote Ham Radio & others.
Other Uses for TangerineSDR:
- HF directional antenna beamforming.
- Widely spaced receivers with accurate timestamping can form a synthetic antenna with narrow angular resolution.
- TDOA- Time difference of arrival. HF direction finding based on time-of-arrival at the receivers.
- Multichannel WSPR, FT-8, other signals.
Future modules possible: Transmitter module, Microwave module, Perhaps phase 4 satellite ground station.
As hams building a Personal SW Station, what do we want to do?
- Know the best frequencies for working DX
- Understand the RFI Environment
- Communicate better during emergencies
For the Scientists:
- Better sample the environment
- Better understand near-Earth Space
The 3-axis magnetometers are PNI RM3100 www.pnicorp.com/product/rm3100-breakout-board/ $20
Mentioned were John Ackermann, N8UR, in reference to Cesium Standard clocks, Tom Clark, K3IO(W3IWI) for very long baseline interferometry, and Scott Cowling, WA2DFI, for SDR info.
Links:
- Video of TangerineSDR mockup, shown by Scotty, WA2DFI at the 2019 DCC in Detroit: www.youtube.com/watch?v=81MlpIpB7Mo
- hamsci.org/basic-project/personal-space-weather-station
- tangerinesdr.com
8:30pm end talk, start questions
8:40pm other comments
Weldon Bauman, KJ6IOD, has a contact for a quantity of surplus DirectTV dishes, probably without the electronics, in case anyone wants to use them for modifying into slot antennas, etc. If interested, contact him at 458-229-0093.
Scott, NA7OM, mentioned an interest in understanding switching-mode power supplies, which are so light and compact compared to the older linear ones, as long as the RFI levels can be controlled well. Also, an idea of contacting the RCC ham radio club to see about collaborations.
Meeting Adjourned at 9pm.
John, KF7UMK
