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  • 2010
    • July
      • Hacked Toaster Oven for SMT soldering
        25/07/10
        I usually hand solder SMT devices in the prototypes I make for clients. Some parts have a large pad on the bottom that needs to get soldered to a plane for heat dissipation or RF grounding. When I can, I put a large hole in the center of the pad so that I can solder it from the bottom after the ot

      • I need a bigger telescope
        21/07/10
        The summer is flying by. I just got back from the 2010 Golden State Star Party (GSSP) up in Adin, California. Adin is a great little town, and the local people are super nice. GSSP is held on a few acres of Albaugh's Frosty Acres Ranch. The organizers do a great job of turning an empty cow

    • June
      • Monitoring WWVB
        10/06/10
        I had a thought about monitoring WWVB on 60KHz the other day. Since I have a really stable source of time (GPS disciplined Rubidium Oscillator) why not log the phase of WWVB relative to the GPS time instead of monitoring the amplitude of the signal?

        I can think of a few ways to do this

    • May
      • Maker Faire
        24/05/10
        I had a really nerdy weekend! I spent Saturday at the Maker Faire in San Mateo. I've been a big fan of Make magazine since it debuted, and I have been to all of the Bay Area Maker Faires. This year was really great. A mind-bending experience as always. Plenty of Steampunk, model rockets, t

      • Decametric Receiver Mods
        02/05/10
        I've been playing with the TenTec 1056 receiver to optimize its performance measuring solar noise. One of its features as a communications receiver is the fairly narrow and adjustable bandpass filter. The manual doesn't say, but it appears to have about a 1KHz bandwidth. This is really

    • April
      • Astronomy Day 2010 at the RFO
        24/04/10
        We are all set up for Astronomy day here at the Robert Ferguson Observatory. We are getting a good crowd for Solar observing which will last until 4:00 PM. Then after a break for a meeting and dinner, we'll be back to show the night sky. I brought my Orion 8" dob, several others will b

      • Radio-SkyPipe Data on-line
        21/04/10
        I have some rudimentary plots available from Radio-SkyPipe on-line now. You can see the data here. The prominent red track is from the 24.8KHz Gyrator II receiver monitoring NLK at Jim Creek, Wa. The flat orange track near the bottom is from the 20.1MHz receiver. I'm still working on that o

      • Orion XT8 Classic - New Base
        18/04/10
        I've had my Orion XT8 Classic Dobsonian Telescope for years and I love it. Last year at the Golden State Star Party we were "treated" to a thunderstorm the first night. I managed to stay pretty dry, but the base of my telescope got wet. Particle Board does not like to get wet.
      • Decametric Antenna Part 2
        16/04/10
        I finally got a relatively rain-free Saturday to install the T2FD antenna up on the roof of the garage. To prep as much as possible, I finished up the bases for the three vertical supports. Here's a picture of one of them:



        These started out as standard 2" PVC "

      • Decametric Antenna, Part 1
        07/04/10
        Now that I have a working receiver, I need a good antenna. The classic Radio Jove antenna is a dual dipole. I actually considered trying to fit one of these on the top of my garage, but I figured my wife and neighbors would not be pleased... Also, it is fairly narrow band, and won't work ver

      • Decametric Receiver Construction
        03/04/10


        Here's the inside of the receiver for monitoring the 20.1MHz region ala Radio Jove. Since I always want to do things the hard way, I didn't buy a Radio Jove receiver. This is a Ten-Tec Model 1056 Direct Conversion receiver kit that I built and modified for solar radio astrono

    • March
      • VLF Hum Canceller Schematic
        23/03/10


        The schematic in my last post looked crappy, so here's a better one. It's a jpeg, so right click on the image to bring up the larger full resolution version.

        Cheers,

        Keith

      • Hum Cancellation for VLF Receivers
        23/03/10
        I mentioned my trick for mitigating mains noise pickup in VLF antenna/amplifier setups at the SARA Western Conference over the weekend, and many people asked for more details. Here are a couple of pictures and a quick schematic.

        The basic idea is to cancel out some of the local mains ele

      • SARA Western Conference
        22/03/10
        I just got around to uploading my pictures from the SARA Western Conference held at Stanford University last weekend. I had a great time, and I'm sure everyone who attended did too. Bill and Melinda Lord did a fantastic job organizing the meeting, and a special thanks goes to Phillip and Debo

      • Solar Monitor Chassis Progress
        17/03/10


        I've completed most of the mechanical work on the Solar Monitor Chassis. This picture shows the front panel with the core module interface on the left and four completed bar graph modules installed. The upper left control is a lighted push-button switch with an integral yellow LED

      • Striking Sparks
        11/03/10
        Last night was the annual Striking Sparks Awardsgiven by the Sonoma County Astronomical Society (SCAS). This phenomenal program has awarded more than 230 telescopes to promising young scientists in Sonoma County California. This is the 25th year of this program that was started by Robert Ferguson,

      • Solar Monitor Module Tests
        01/03/10

        I finished work on the Core module, so it's time to put a few things together to see if they work as planned. Here you can see the Core module and a Bar Graph board wired together along with a speaker and the transformer. All the functions work as intended, although I decided to make a

    • February
      • Solar Monitor Core Module
        24/02/10

        This is the core of the Solar Monitor project. There is a schematic here. This board holds the A/D converter which takes the signals from up to 8 bar graph/amp boards to be digitized and logged by Radio Sky. It also does the power distribution and some other house keeping functions.
      • Cloud Computing
        22/02/10
        I was thinking about "Cloud Computing" today as I was driving along with the roof down. When you have been a nerd as long as I have, you begin seeing long term patterns in technology. Cloud Computing is a phase in computing that we have experienced in the past.

        The earliest co

      • Solar Tracking VHF Antenna Part 2
        21/02/10
        Figuring out how to make the antenna track the sun was fun and interesting. I started out with a book called "Sundials: Their Theory and Construction" by Albert E. Waugh (ISBN: 0-486-22947-5). It takes you through the basics of how the sun appears to move through the sky. Remember that

      • Solar Tracking VHF Antenna Part 1
        20/02/10


        This is my semi-homemade alt-az mount with broadband VHF antenna attached, ready to go on the roof. Well, almost ready... I still need to do some testing on the ground. It's a lot more convenient than climbing a ladder to fix something.

        It all starts with a pretty gene

      • Radio Astronomy - SARA Western Conference
        19/02/10
        I'm really looking forward to the upcoming Western Regional Conference of the Society of Amateur Radio Astronomers coming up next month at Stanford. It's just too much of a trek for me to get from Sonoma County, CA to the big SARA meeting at Greenbank in the summer. I do hope to make th

      • Radio Astronomy - Multi-Frequency Monitor Part 1
        19/02/10
        Now that the seismometer has been delivered, I can get back to work on my Multi-Frequency Monitor project. The basic idea is to monitor radio activity in several parts of the the spectrum, from VLF up to Microwaves. I was inspired to do this because of the long, deep, solar minimum we just experie

      • Seismometer Build Pt. 2
        16/02/10
        Well, here's the finished seismometer ready for delivery. It was picking up the heavy surf off the Sonoma County coast for the last week, and also recorded a 3.0 at The Geysers.
        To get here, I changed the upper suspension to be mostly rigid. It's hard to tell in the photo, but the a

      • Happy Birthday Charles Darwin!
        12/02/10
        In my book, Charles Darwin was one of the great original thinkers. I put him right up there with Galileo in his willingness to question conventional wisdom and make the leap from creation to evolution. He agonized over his theory, knowing that everyone, including his family, would have a very diff

      • Seismometer Build Pt 1.
        11/02/10

        This is a side view of a Lehman style Seismometer I am building for a friend. I found some great base material at Bataeff Salvage here in Santa Rosa. It's 1/2" plate aluminum, about 6" x 18". The vertical section is 3/4" galvanized pipe and fittings. Here I'm j

      • Welcome to my Amateur Science Blog
        08/02/10
        This is the first entry in my new blog dedicated to Amateur Science of all kinds. I use the word "Amateur" in the original sense: One who pursues an interest just for the love of it. My focus lately is Radio Astronomy, but I am also interested in Seismology and darn near anything else ab