Month: July 2009

Arizona Scorpions and CactusCon

A message to QRP-L from Paul Harden, NA5N about this event almost had me seeking flight reservations. It really sounds great. Wish I could go. But wait! A virtual visit is possible, because they plan on providing live video streams of the presentations. And last year’s talks are also available. Go Scorpions! Check it out:
http://www.azscqrpions.org/CactusCon2009.htm

Shep: UHF and Deep Space Communications

On this one, it takes a while for Shep to get to the radio stuff, but it is worth the wait. Or you could fast forward to around the half-way point (but in doing so you will miss the commercial for Miller High-Life, and Shep’s discussions of Monolopy and the Game of Love).

http://ia310115.us.archive.org/2/items/JeanShepherd1965Pt1/1965_04_15_Radio_Signals.mp3

Homebrew Telescope Finds Earth-sized Scar on Jupiter

Wow! Amateur astronomer Anthony Wesley in Australia was the first one to see this new scar on Jupiter. Reminds me of the Shoemaker-Levy 9 comet impact back in 1994. I saw the results of that strike direct from my front yard in the Dominican Republic using a Tasco 4 inch reflector. (The story of that adventure is in the book, “SolderSmoke — A Global Adventure in Radio Electronics.”) Exciting stuff!

Icing on the cake: The discovery was made with a HOMBREW telescope! Here is the web page of the fellow who made the discovery:
http://jupiter.samba.org/
I really enjoyed reading his account of the discovery.

Here is a news article about the event:
http://www.cnn.com/2009/TECH/space/07/24/hubble.jupiter.scar/index.html

Apollo 11

I was 10 years-old and totally involved with the mission. Armstrong
was my hero. I kept a scrapbook (still have it). There is an
interesting Italian angle: Collins was born in Rome. His dad was with
the US Embassy. Glad to see Buzz is doing well. There is a great story
in the book Moondust about his dealings with an obnoxious reporter. I
think Buzz handled it perfectly.

Taming the Beast: Progress on the One FET Regen Rig

I went back to work on the ET-1R, my relay-based version of the single FET transceiver (check the index on the left under Minimalist Radio for more on this). The contest this weekend (was it CQ WW DX?) gave me plenty of signals to tweak the receiver with. I finally got the RX in the right freq range, and I have a nice banset/bandspread arrangement with two variable caps. I attacked the dreaded hand capacity issue via the use of non-conducting attachments to the capacitor shafts (one is the cap from a pen, the other is a piece of wood from a clothes pin).

The slaughter of innocent MPF-102s has ended (some victims are visible on top of the SPRAT). The culprit was NOT voltage spikes from the relay coil (although that might have contributed). Instead, what was happening was that I had the gate voltage set way too high on the transmit side. Whenever I powered up the rig, it was for an instant in the transmit mode (before the relay kicked in). The high voltage jolt on the gate was enough to kill the FET.

You can see the transmitter tucked in behind the relay. It moves my SWR meter on key down, so I’m confident I can get at least one QSO (perhaps across Rome) with this rig. Then, I intend to retire it. It will probably be a few years before I forget the pain and decide to build another minimalist regen rig.

Into Space (almost) with the Basic Stamp

L. Paul Verhage has been a leader in the edge-of-space balloon game for a long time now. This morning, Hack-A-Day led me to a site that has an on-line version of his book, and a collection of his balloon and Basic Stamp articles for Nuts-and-Volts. Inspirational stuff.

Here it is: http://www.parallax.com/tabid/567/Default.aspx

Clayton’s Cool Solar QRSS Rig, WA5DJJ, TESLA!

Clayton (who is NOT crazy) has put together a really neat solar-powered QRSS rig with the two wires for the dipole antenna sticking out the ends of the transmitter box. During the testing phase he went the extra mile by first freezing the circuit into a block of ice and then heating it up in an oven. I guess he really wanted a wide range of temperature data! Clayton’s web site on the project is very interesting and very well done. Check it out:
http://clayton.isnotcrazy.com/mept_v1

In other QRSS news, David, WA5DJJ, just back from vacation, fired up his QRSS rig only to discover that there are no grabbers on in North America. What’s up with that? Can someone out there help out OM DJJ?

Did you guys see that Google is today marking Tesla’s birthday. Clearly there are some Knack vicitms in the Google-plex.

Links from #111: W7ZOI, VU3ICQ, AA1TJ

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

SolderSmoke Podcast #111

Lunchtime on Ponza (with Palmarola Island in the background)

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

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.