Here is the excellent discussion of bi-directional amps I mentioned. From the web site of W7ZOI:
http://w7zoi.net/Bidirectional%20Matched%20Amplifier.pdf
Here is Farhan's new JBOT 5 watt final amplifier:
http://www.phonestack.com/farhan/jbot.html
Here is the mysterious (and perhaps diabolical) Xtaflex from AA1TJ (the first rig EVER to promise "buns of steel.")
http://mjrainey.googlepages.com/xtaflex
Podcasting since 2005! Listen to Latest SolderSmoke
Monday, July 6, 2009
Sunday, July 5, 2009
SolderSmoke Podcast #111
http://www.soldersmoke.com
In SolderSmoke 111:
July 5, 2009
Ponza and the Pontine Islands
The Xtal Set Society -- Great guys!
Spark plugs as lightning arresters
The Grundig Mini 300 SW receiver
Jupiter from Rome and from Mars
Saturn from the window
More tremors
Back to visual MEPT
Is my antenna down, or is it conditions?
W7ZOI on bidirectional amps
Farhan's simple "JBOT" 5W BJT amp
AA1TJ's Xtaflex
Regens from hell
WD-40
Sprat 139
Arthur C. Clarke's "Voices from the Sky"
MAILBAG
Check out the new book "SolderSmoke -- A Global Adventure in Radio Electronics. " Read the first chapter here:
http://www.lulu. com/content/ paperback- book/soldersmoke /6743576
Labels:
SolderSmoke Podcast
Saturday, July 4, 2009
The Pontine Islands
We were out on Ponza island this week. Amazing place. Part of the Pontine Island group. Brave Ulysses was an earlier visitor. Roman emperors used it as a summer place. It is only about 33 km from the mainland and you can get there from Anzio in about one hour by fast hydrofoil. We took a small boat over to the beautiful island of Palmarola. I did a bit of shortwave listening. More about this trip in the next SolderSmoke.
Labels:
Italy
Monday, June 29, 2009
Sunday, June 28, 2009
Friday, June 26, 2009
VK5DGR's QRSS Rig
David, VK5DGR, built this very fine QRSS rig, and is currently shaking up the grabbers with 20 mW.
I really like his way of putting that power level in perspective:
"Look around your room and find a glowing LED. Well a typical red LED has 2V and 10mA flowing through it, or about 20mW. It can barely make it a few metres to be detected by your eyes. Imagine detecting it at a range of 1200km! That’s what I find remarkable about QRSS - tiny power levels that go a very long way."
For more info, go to David's "Beer, Coffee and a little DSP" blog:
http://www.rowetel.com/blog/?p=118
I really like his way of putting that power level in perspective:
"Look around your room and find a glowing LED. Well a typical red LED has 2V and 10mA flowing through it, or about 20mW. It can barely make it a few metres to be detected by your eyes. Imagine detecting it at a range of 1200km! That’s what I find remarkable about QRSS - tiny power levels that go a very long way."
For more info, go to David's "Beer, Coffee and a little DSP" blog:
http://www.rowetel.com/blog/?p=118
Labels:
QRSS
Wednesday, June 24, 2009
Jupiter from Rome (and from Mars)
I was up earlier than usual this morning and decided to do some planetary astronomy from the Eternal City. The Heavens Above web site showed Jupiter high in the pre-dawn sky. A quick look out the window confirmed that from our courtyard it would be clear of the Trastevere rooftops. Soon the six inch Dobsonian Newtonian reflector was in operation. I got a very nice view of Jupiter and the four Galilean moons through fairly clear Roman skies.
The view was similar to that of the picture above. There are a lot of better shots of Jupiter available on the 'net, but this one is a bit unusual. It was taken from Mars:
Jupiter/Galilean Satellites: When Galileo first turned his telescope toward Jupiter four centuries ago, he saw that the giant planet had four large satellites, or moons. These, the largest of dozens of moons that orbit Jupiter, later became known as the Galilean satellites. The larger two, Callisto and Ganymede, are roughly the size of the planet Mercury; the smallest, Io and Europa, are approximately the size of Earth's Moon. This MGS MOC image, obtained from Mars orbit on 8 May 2003, shows Jupiter and three of the four Galilean satellites: Callisto, Ganymede, and Europa. At the time, Io was behind Jupiter as seen from Mars, and Jupiter's giant red spot had rotated out of view. This image has been specially processed to show both Jupiter and its satellites, since Jupiter, at an apparent magnitude of -1.8, was much brighter than the three satellites.
Text and image from:
http://publicdomainclip-art.blogspot.com/2006/06/space-final-frontier-jupiter-and-moons.html
The view was similar to that of the picture above. There are a lot of better shots of Jupiter available on the 'net, but this one is a bit unusual. It was taken from Mars:
Jupiter/Galilean Satellites: When Galileo first turned his telescope toward Jupiter four centuries ago, he saw that the giant planet had four large satellites, or moons. These, the largest of dozens of moons that orbit Jupiter, later became known as the Galilean satellites. The larger two, Callisto and Ganymede, are roughly the size of the planet Mercury; the smallest, Io and Europa, are approximately the size of Earth's Moon. This MGS MOC image, obtained from Mars orbit on 8 May 2003, shows Jupiter and three of the four Galilean satellites: Callisto, Ganymede, and Europa. At the time, Io was behind Jupiter as seen from Mars, and Jupiter's giant red spot had rotated out of view. This image has been specially processed to show both Jupiter and its satellites, since Jupiter, at an apparent magnitude of -1.8, was much brighter than the three satellites.
Text and image from:
http://publicdomainclip-art.blogspot.com/2006/06/space-final-frontier-jupiter-and-moons.html
Labels:
astronomy
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