Radio Signals from Jupiter and Io on 17 Meters

Jupiter and Io montage captured by the New horizons spacecraft.
The Jupiter image is false-color near IR data obtained with the LEISA instrument, built at GSFC.

I try to always read the QRP-L postings of NA5N -- Paul always has something interesting in his messages. Today I found this:
Jupiter emissions peak around 18-22MHz; they are a function of when the moon Io crosses certain longitudes of the relatively fast spinning Jupiter. There used to be a couple of calculators online (haven't checked lately) as to when the L-bursts should occur. The timing is quite predictable; detecting them on every predicted occurrence is not. You have to have an antenna with a little bit of gain. The signals are generally weaker (that is, near the atmospheric noise level) than can be detected with a dipole. With a fairly decent setup, the Jovian L-bursts sounds like ocean waves crashing on a distant beach, just barely above the noise level. The S-bursts sounds like random pulse type static in short bursts. These are harder to detect than the L-bursts.

I had known about the Jovian radio emissions, but I didn't know that the moon Io was involved. For me, Io's involvement somehow makes this even more interesting. Jupiter and its moons (including Io) are some of the few celestial objects I can regularly see from central Rome.

Here is a good description of Jupiter's radio signals, and Io's role in transmitting them:
http://radiojove.gsfc.nasa.gov/library/sci_briefs/decametric.htm

And here is an interesting article about the discovery (50 years ago) of these signals:
http://radiojove.gsfc.nasa.gov/library/sci_briefs/discovery.html

SolderSmoke Podcast #108

http://www.soldersmoke.com

In SolderSmoke 108:

May 24, 2009
Hubble Space Telescope Repair Mission
WSPR: W3PM sees my sigs, back to visual (briefly), on to Slow Hell.
Ubuntu ham radio software
Time nuts
Jean Shepherd gets his Class A license
"SolderSmoke -- The Book" Good for summer vacation reading.
SPECIAL REPORT FROM DAYTON - FDIM BY BOB W8SX
MAILBAG

CHECK OUT THE BOOK: (First chapter preview available)

http://www.lulu.com/content/paperback-book/soldersmoke/6743576



73 from Rome

Tech Details on ET's "Phone Home" Beacon Rig

Mark "MOJ" Johnson, W8MOJ, sent me a really amazing 73 Magazine article. It is from the APRIL 1983 issue. (The month of publication set off my April-fool alert alarm, but this is for real.) When Steven Spielberg was making ET, the producers contacted Bell Labs and asked for help in designing the rig that ET would use to phone home. A ham, Henry Feinberg, K2SSQ, got the job. In the article, Henry wrote: "What Spielberg wanted was a beacon transmitter, something to say, 'Here I am, Come and get me!' I reasoned that three main parts wee needed for a basic beacon: a means of producing a message, a programmer to repeat the message, and a way of transmitting the signal into outer space."

Later, in describing the keying device, Henry wrote: " The surface of the saw blade was coated with several layers of spray paint, which served as insulation, preventing the bobby pins from contacting the metal blade. The message was programmed on the blade by carefully etching through the paint. "

OK, that does it. Time for me to go back to the Trastevere flea market to pick up some more cheap clock drives... and maybe some circular saw blades. I need to get going on my mechanical QRSS one-transistor becaon project.

REAL Hams Make Their Own Crystals....

Bill: You say you buy your crystals from the electronics store? Real homebrewers grind their own crystals. See attachments. Russ

After reading this I was feeling like a complete APPLIANCE OPERATOR. But wait a second Russ -- that's a KIT! Real homebrewers don't need KITS to make their own crystals! And remember, you are talking to a guy who has used iron pyrite and a phosphor bronze to detect radio waves. That means I have homebrewed my own DIODES! ;-)

Thanks for the cool pictures Russ. Those were the days...

Seeing my WSPR signal

Graham, G3ZOD, sent me this WSPR screen-shot. He writes:

Hi Bill. Thought you might be interested in a screen grab of yourself. You're the near continuous signal along the centre of the waterfall just below 200 on the vertical axis.Not DX from Italy to England, but I'm using an indoor wire antenna and I usually receive you for short periods only - never seen such a consistent signal before. By the way: I think your computer clock may be a couple of seconds off according to the DT values; I have mine resync every 6 hours and my clock is generally within 150 milliseconds.
73 de Graham G3ZOD

Thanks Graham! The consistency of my signal is no doubt due to the fact that I have no receive system here yet, so on the WSPR software, in the "T/R Cycle" box I had "TX" checked. So I was "key down" most of the time. Your screen shot made me realize that this might not be the most neighborly thing to do -- someone else on the same freq might be QRMd by my 20 mW DSB sig. So I think I'll ratchet down the T/R cycle here.
My computer clock is erratic. I have to tweak it each day. I know there is a program out there that automates this -- haven't gotten to that yet. 73 From Rome

Shep's Class A License, Part II

I didn't mean to leave you guys in suspense. Here is the exciting conclusion.
EXCELSIOR!

Jean Shepherd Gets His Class A License

I was drifting off into Linux-land, but an e-mail from OM Gene, K8EE, brought me back. I'd thought that we had already unearthed all of the best ham radio episodes of the Jean Shepherd shows. WRONG! K8EE sent me YouTube recordings of the January 7, 1964 show on WOR New York. Gents, all I can say is that you should stop what you are doing, and listen to this. (And don't miss the exciting conclusion in part 2!)

"Mr. Rupp, what do you know about the Mu of an '807?" Indeed.

Ubuntu

As SolderSmoke listeners know, I'm not really a software guy. In fact, I'm only a marginally competent user of software. But I've taken a liking to Ubuntu Linux. It works, it is user friendly, and it seems to have developed a very cool African cultural thing around it. Check out the names of the various versions and you will see what I mean:

4.10 Warty Warthog
5.04 Hoary Hedgehog
5.10 Breezy Badger
6.06 Dapper Drake
6.10 Edgy Eft
7.04 Feisty Fawn
7.10 Gutsy Gibbon
8.04 Hardy Heron
8.10 Intrepid Ibex
9.04 Jaunty Jackalope
9.10 Karmic Koala (NEXT ONE) October 2009

OK, now back to the radios...

KO7M Suddenly Goes Manhattan

Perhaps he picked up the vibrations from Dayton and FDIM where they were conducting a Sudden Receiver build-a-thon... Jeff, KO7M, (aka the lucky guy with the Piper Cub) recently tried out Mahanttan-style construction -- he built an NE602-LM386 Sudden Receiver... and liked it.

Jeff writes:

Believe it or not, I have never built anything Manhattan style… So, I decided to give it a go and built a little 40m DC receiver designed by Rev. George Dobbs G3RJV consisting of a NE612 and LM386. I have included a shot of it below. I was very pleased with this building style and think I may adopt it going forward. In particular I like how easy it is to make changes. I just used tin snips to make the pads. For the 8 pin IC pads, I cut them 2 cm square and used a hacksaw to saw between the IC pins and up the middle to separate the pin pads electrically by removing the copper. Make sense? Very simple to then bend the IC pins 90 degrees and solder them down. Preaching to choir, I know… But it takes some us a little longer to get on board, eh? J I was very pleased with the outcome.

I like Jeff's technique for the IC pads. I will have to try that.

SolderSmoke 108 will feature an interview with George Dobbs in which he talks about the Sudden Build-a-thon.

W3PM Hears the WSPR Rig he Inspired

I got a nice e-mail from Gene, W3PM. Gene's simple homebrew SSB rig for WSPR provided the inspiration that got me into the WSPR mode. We'd been exchanging e-mails a while back, then he mentioned that he would be away... Turns out, he ended up within range of my 20mW WSPR sig. (The picture shows Gene doing some maritime mobile satellite operating from the QEII in 2002.)

Hi Bill, I just wanted to let you know that I hear your 20 mW WSPR signal each morning around 0500 to 0700 UTC. Your signal strength varies between -21 and -26 dBm.

I am currently on vacation in Fettercairn (GM4YRE, IO86ru), Scotland which is located about 30 miles SW of Aberdeen in the northeastern part of Scotland. I have very limited internet access; therefore, I cannot report WSPR spots in real time. My WSPR transmitter is active most days on 30 meters until we leave Scotland... I run one watt to a low doublet antenna.

73/72 Gene W3PM GM4YRE

Atlantis, HST in Front of the Sun

Check out the little black marks in the lower left of old Sol. That's Shuttle Atlantis and the Hubble Space Telescope (you can see it in more detail below). The picture was taken from Florida by Thierry Legault. He calculated when the spacecraft would be aligned with the sun from his Florida location and took the shot. Well done. More innovative astrophotography at his site: http://www.astrophoto.fr/ Note: Too bad we don't see any REAL sunspots!

Scary Stuck Bolt on Hubble Space Telescope

They had a scary moment during yesterday's space walk. They were trying to get the old camera out. One of the bolts wouldn't turn. It has been in space for 16 years They kept adding more torque, and they knew they were approaching the point at which the bolt would break, preventing -- forever -- the replacement of the camera. In what looked like their last attempt, the got it turning. Bravo! The live coverage via NASA's online TV is really superb. They are using helmet-cams, and you get to see just what they see.

NASA put together a video on the personal stories of the crew members. I think it is a good thing to show kids (Billy has already seen it, Maria is next):