Just go to http://soldersmoke.com. On that archive page, just click on the blue hyperlinks and your audio player should play that episode.
http://soldersmoke.com
As I mentioned earlier, computer problems have delayed the SolderSmoke podcast (don't worry, parts are on the way). They have also knocked me off the WSPR system. So I switched over to QRSS mode and am now pumping out about 20 milliwatts of upside down sloooooooooow FSK on about 10140050 Hz. (Don't you like how in QRSS you find yourself giving the frequency not in kilos or megas, but in just plain Hertz? If I get into a retro mode I may start giving them in cycles.) During daylight hours in Europe you should be able to watch my little signal arriving at ON5EX's station in Belgium. Just look down on the right on this page for a live view of Johan's receive screen.
I noticed this morning that Mike, AA1TJ has moved and updated his very fine site. Check it out: http://www.aa1tj.com/radio.html Be sure to click on the link that lead to info about Mike mountain-top work site. Like I said, truly the kind of job that Knack victims dream about.
Rumor has it that Dan's Small Parts is back in operation after a winter break.
No podcast this week. I have two excuses: 1) Computer problems (a long, sad story), and 2) we were once again out in the Sabine Hills. Above is another look at the olive grove QTH. That solar panel thing on the right is an automatic weather reporting station installed by the Region of Lazio. Those trees behind the weather station are olive trees.
We had clear skies this past weekend, and with Mars approaching full opposition, I had the telescope out. We got some better views of Mars than we had last week. When the atmosphere (ours!) would settle down a bit I could make out some of the dark "canali." The Northen polar cap was very visible. The moon was bright (first quarter I think) and so I was wondering if we'd be able to see the M31 galaxy in Andromeda. Even with the moon close in the sky, I had no trouble finding the galaxy using my old Soviet-made 7X50 binoculars. We also looked at the North America nebula in Orion's sword (very appropriate as we had Canadian friends with us).
My telescope (above) has a simple but effective Dobsonian mount. (This system is named for the amateur astronomy guru John Dobson -- interesting guy.) The 'scope basically slide on teflon pads. These pads need a bit of lubrication from time to time. Mine were getting a bit sticky, so I started to look around for something to to grease the teflon. The solution was literally all around me:
Worked like a charm!
Also got on the air with the HW-8 and worked stations on 80, 40, and 20, including two QRP stations.
In "SolderSmoke -- The Book" I describe the quest for deep understanding of the circuits that we build and use. There is some discussion in the book of the role of mathematics in this quest. A while back a reader e-mailed me on this subject. In the hope of stimulating a discussion, I'll present the key paragraph from that e-mail here (the author will, for now, remain anonymous):
I appreciate your quotes from Feynman, Asimov, etc. about not really being able to fully understand everything. As a math teacher I can say that one of the biggest misunderstandings about math is that it "explains" the phenomena ofphysics and engineering. (Science and math teachers are notorious for sayingto a student who has just asked a "why" question things like, "well the math is a little bit more complicated than what you can handle right now. Wait untilyou have had a year or so of calculus.") In reality it's the exact opposite! The math equations actually hide the answers. They are very good at accurately describing phenomena, or at predicting what will happen next, but they can never answer the question of why one equation works and another does not. We get very comfortable with allowing the familiar math equations to hide our inability toreally answer the "whys."
This really resonated with me. In my effort to get a better grasp of mixer theoy a lot of people seemed to be simply pointing me to the trig equations, and equating a knowledge of those equations with an understanding of how the mixer circuits really work.
Of course, I don't mean to be anti-math here, but I thought the e-mail on the limits of mathematics was very interesting.In "Empire of the Air" Tom Lewis wrote, "At Columbia, Edwin Howard Armstrong developed another trait that displeased some of the staff and would annoy others later in life: his distrust of mathematical explanations for phenomena of the physical world. All too often he found his professors taking refuge in such abstractions when faced with a difficult and seemingly intractable conundrum... Time and again as an undergraduate at Columbia, Armstrong had refused to seek in mathematics a refuge from physical realities."
Like everyone else I was saddened to hear of the passing of Dave Ingram. We've all been inspired by Dave's magazine articles, columns, and by his books. I'll always remember his QRP transmitter in a pen! It was my privilege to talk to Dave once, on the air. I was on 30 meter CW with a brand new,scratch-built, HB QRP transceiver. I was in Virginia. I recognized Dave's call, and was thrilled when he came back to mine. I told him I was running homebrew QRP, and that I'd found inspiration in his articles. I know he was happy to hear that. 73 OM! Dave's wife Sandy put a nice message on his blog: http://k4twj.blogspot.com
I mentioned that Billy and I had spotted the Andromeda galaxy. The photo above (not by us) is sort of close to what we saw. The astronomy books usually show these spectacular images of Andromeda in all its glory. But those pictures come from long exposures through big telescopes. Through our little six inch reflector, Andromeda looks like a cloud, not quite as defined as the one in this picture. This picture is a 4 minute exposure through an ordinary digital camera using a 300mm telephoto lens. (From: http://www.prairiehillfarmiowa.com/prairiehill/Home.html)
It is a real thrill to look at Andromeda. That little cloud represents 300 billion stars, and they are around 2.5 million light years away. So when you look, you know the photons hitting your retina started their trip LONG before there were homo sapiens. Icing on the cake: A satellite went through the telescope's field of view just as was looking at M31.
Another nice thing about Andromeda galaxy is that you can see it with the naked eye (you have to know where to look!). Because of this, people have been observing it for quite some time. Here is the first known drawing of M31. This is the work of the Persian astronomer Al-Sufi, and was done in year 964. The Persians imagined a constellation in the form of a fish in that part of the sky. Note the little cloud near the mouth of the fish -- that's M31.
Until 1923 astronomers thought M31 and other "nebula" were just clouds within our galaxy. The thought was that the Milky Way was the only galaxy. But then Edwin Hubble got some distance readings (using variable stars) on Andromeda and realized that he was looking at an entirely separate galaxy. That was a BIG discovery.
Ed, KC2TYP alerted me to this one: Jeff, K7JPD, has a very intriguing blog post about homebrew transistors. I suspect AA1TJ will have a rig made of these things on the air within a week. Check it out: http://jeff-duntemann.livejournal.com/227856.html
How's that for a shack! Elisa rescued me from the frigid front porch and got the owner to agree to let me use this little building. You can see the VW solar panel in the window.
Here's the view:
Here's a little silent video we shot of the Sabine Shack:
The HW-8 runs of a 7AH Gell Cell that is charged by my Volkswagen panel. Antenna is a doublet fed by TV twin lead. The Blackberry provides internet access, and I can send in blog articles from it by e-mail.
Ian Sharp in Britain took this image at 0:54 UT January 4, 2010. The North Polar Cap is huge and obvious. The slightly bright region on the southern limb (top) is the dusty Hellas basin.
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After months of looking at Jupiter, we now have a good view of Mars. On Saturday night we had a "Mars-rise" over Monte Calvo shortly after sunset. Mars is really bright now (explained below) and the distinctive red color really jumps out.
I didn't take the picture, but the shot above gives you a good idea of what I was looking at on Saturday night. The Northern polar cap was very apparent in my six inch Newtonian Dobsonian. It looked like it had a dark border around it. Martian North is at the bottom in this shot. It is Spring in the Northern hemisphere of Mars now.
Mars is now in a very good position for observation from Earth. On January 27, it will be in full opposition:
So hey, this is the time for those of you who are hoping to win the Elser-Mathes Trophy! Aim those Yagis and be sure to tune UP!
No podcast today because we are out in the Sabine hills.But here is a report on activities here; RC plane was a flop. Advice from WA6ARA and others helped, but wings are now really messed up. Big success in astronomy: clear skies and no moon on Saturday. We had a really beautiful "Mars rise" and were able to see the polar ice cap. Then we spotted Andromeda galaxy naked eye, and then viewed it in the scope. Awesome. I'm on the HW8 now. There is a contest but I've managed a few real QSOs. Back to Rome tonight.
SolderSmoke listeners might recall that Jack Dunigan e-mailed me prior to his move to Uganda. Jack had been listening to our stories about QRSS and WSPR and was thinking about setting up an East African beacon. Jack in now in Uganda and on the air as 5X7JD. He has a beautiful and very interesting blog. Check it out:
(Jack: Maybe run WSPR using your computer and the Icom at low power, and then use the Tuna-Tin-Two for a separate QRSS beacon. You need an SSB rig for WSPR, but a simple K1EL keyer hooked up to the Tuna-Tin is all you would need for visual QRSS. The TT may need some modification to put it on 30 meters. Let us know if you need help, parts, crystals, etc. It would be a real hoot to have a Tuna Tin beacon from Uganda!)
Jack's blog is filled not only with tales of ham radio in Africa and Jack's personal radio roots (in his Dad's TV repair shop), but there is also information about the work that took Jack and his wife to Africa. Here is his description of it:
Aidchild, the organization for whom I work here in Uganda, cares for orphans living with Aids. There are two homes filled with kids for whom we care completely. This means we provide complete care because they are in every respect our own children. We also provide clinical and laboratory services for about 3000 more children. All of this costs money, lots of it. You can check us out at www.aidchild.org
We raise money through donations, but we also have started businesses here in Uganda to provide funds. We have an art gallery and shop at the Sheraton Hotel in Kampala, a gallery and cafe on the Equator, and a restaurant here in Masaka called Ten Tables (any guess as to how many tables there are?). But caring for Aids children is not inexpensive. So we can always use more funds.
From Jack's postings you also get a sense of the personal sacrifices and hardships that come with his kind of work: scroll down to his posting about malaria and you will see what I mean. As we all watch the suffering in Haiti, it is a good time to think about the many good people like Jack and his wife who are working hard to help our fellow human beings in difficult third-world areas.
Speaking of Haiti, of course the situation is unspeakably bad. We feel real connections to it: My wife is from the same island (from the Dominican Republic). When I was stationed in Santo Domingo, I traveled to Port-au-Prince, and went to many of the places that you now see (crumbled) on TV. Here in Rome, the principal at our kids' school is Haitian. And I have friends in our embassy there. As a kid, one of my first DX contacts was with HH2JT -- Jules Tomar (I still remember getting his QSL). I see that the good fellows at G-QRP have made a contribution to the relief efforts. We should all follow their lead. Graham, G3MFJ, reports that the club made their donation to : http://www.dec.org.uk/donate_now/
From London I used to talk to Phil, VK6ADF, on Echolink. We have a lot of interests in common. This may be due to the fact that we were both born in the International Geophysical Year. Phil is now reading "SolderSmoke -- The Book," so we will probably discover other areas in which we have crossed paths. This week, I decided to get back onto Echolink, and in my first session I was looking for OM Phil. He wasn't on, but, IN A VERY MYSTERIOUS TWIST, that morning he sent me an e-mail. Spooky, eh? Anyway, yesterday we got on Echolink and covered our usual wide-range of tech topics. Phil alerted me to a web site called Real Flight that provides an on-line simulator for Radio Controlled airplane pilots. Obviously Billy and I could use some time in the simulator! Phil is also into WSPR and as we spoke I fired up my 20 mW DSB WSPR rig. I was immediately heard by an Irish station, and Phil almost instantly saw the report on the WSPR database. I noticed that the EI station was reporting that I was on 40 meters, when in fact I was rock-bound on 30. Again, as Phil and I talked, I went to the WSPR chat section and asked about the freq discrepancy. Another VK6 (a friend of Phil's!) answered my question (a simple set-up problem). Small world. Phil and I have similar curmudgeon-like thoughts on Surface Mount Soldering, and he seemed sympathetic when I said that I think I am more of a "Hardware Defined Radio" guy. Again, this may be an IGY thing. Oh yea, almost forgot: We're not crazy about LINUX either. We are only a few short steps away from the "SPARK FOREVER" mentality and full-fledged Luddite status. One interest that Phil and I DO NOT share is Six Meters. Phil is now addicted to the Magic Band (which I still consider to be a white noise generator). Check out his video on his six meter yagi.
Whenever I find myself in need of some radio-inspiration, an e-mail from Mike, AA1TJ, seems to pop up in my inbox. This morning's message and the associated video (above) were especially inspirational. Mike was e-mailing Steve, WA1HFF.
Hi Steve, Thanks for the message and the great QSO! I was running my one transistor transceiver that I call the Reggie. You can read about it on my webpage at
My antenna is nothing to write home about; just an end-fed half-wave wire bent into an "EL" at 35 feet.
I've made just over 240 contacts with my Reggie in a little more than a year's time; working 19 states. My best (and only) real DX was the Bahamas. All of these contacts were made with no receiver gain on this end; just a pair of diodes fed by a one-transistor BFO, and onto the headphones.
A couple of fellows have built their own Reggies, so you might run into one on 80m now and then. I've made three Reggie to Reggie QSOs thus far.
Steve, last night I was trying something new; I ran a loudspeaker from an audio amplifer connected to my Reggie. What's unusual is that my audio amplifer was made from three, common power supply rectifiers (1N5401's). I'm not kidding! It's a nearly forgotten circuit from 1954 that I (re)stumbled upon a couple of weeks ago. It uses the phenomenon of PN junction charge-storage to produce amplification.
Last week I used two diode gain stages for a total power gain of 48dB to drive my headphones. Yesterday, I added a third diode gain-stage and connected it to a loudspeaker for shack-filling audio volume.
I made a video of last night's setup (the same setup I worked you with). You can see it at
Thanks again for the nice contact last night, Steve. You were armchair copy here! :o)
Best wishes, Mike, AA1TJ
Here's a question for Mike: Can you build that kind of amplifier with homebrew point-contact diodes? If so, you'd be opening up the possibility of a homebrew solid state receiver with homebrew solid state devices. Oh man, this stuff makes me feel like such an APPLIANCE OPERATOR.
We are thinking that olive groves are not quite as forgiving as the corn fields that the kid in the picture is using. And the bit about "no experience needed" probably should have a "as long as you don't mind crashing." Oh well, I guess crashing is part of the learning experience. But a quick review of the pertinent R/C airplane forums reveals there may be problems with this wing design: Apparently when it stalls, one wing stalls before the other (i.e. it "tip stalls"), with catastrophic results. The plane has a very comforting ACT ("Anti-Crash Technology") feature, but the forums advise that this feature may cause more crashes than it prevents.
We have the plane back on the Rome workbench this weekend. Crazy glue and tape are being applied. We will be back out at Chinghale International Airport (i.e. a clearing in the olive grove) next weekend to see if we can get a few good flights out of this thing.
Radio notes: The radio control system is on 27.145 MHz FM.
I mentioned Antonio Stradivari in SolderSmoke 120, but I felt a bit guilty about it, because there wasn't much of a connection to radio. But Nick, KB1SNG, has come to the rescue. Nick sent me this interesting article that discusses POSSIBLE connections between the quality of Stradivari's violins and the sunspot count. Check it out: http://news.nationalgeographic.com/news/2004/01/0107_040107_violin.html
A recent article in The Economist alerted me to the fact that OM Stradivari was busy in the shack, churning out mechanical audio oscillators well into his 90's. I thought that Stradivari's late start, and his success in his senior years makes him an inspiration for many of us. A quick look at the Strad-Wiki page confirms this: Stradivari didn't really hit his stride until age 54, and did his best work between age 54 and 81.
Now that my HW 8 station has been moved indoors (good thing -- there was snow on the hilltops this week!) I had to put up a new antenna. I decided to go with the same design that I had earlier: a dipole fed with TV twin-lead. I knew I needed a bit more wire than I had used in the original -- I had trouble getting that antenna to tune up on 80. So I went to the local hardware store and asked for 20 meters of AC line cord. That cost me 8 Euros. Not bad. We had a nice sunny afternoon on Sunday -- Billy and I took the line cord out into the olive grove and pulled apart the two wires. (Hint: Start from the center, and pull slowly, or else the cord will get all twisted and a two minute job will turn into a twenty minute exercise in untangling.) I got to use some of those Radio Shack "solder strips" -- I just wrapped a few around the connection points and applied heat from a cigarette lighter. I put some parachute cord (550 cord) over a conveniently placed tree branch using the venerable rock and rope method. One throw was all that it took. The radio gods were smiling on this project. Success! With the Trastevere flea market Pi network, the thing tunes up nicely on 80, 40, 20, and 15. I notice that the cheap CB SWR meter that also I picked up at the flea market doesn't seem to sample much RF at 80 meters. I'm guessing that the designers were very focused on 27 MHz. I quickly worked stations all over Europe, and even worked one station in Israel. I worked G4OEC in Somerset -- I immediately thought of Tim Walford, and asked OM OEC if he knew the wizard of the Somerset farm. Mac said his village was far from Tim's QTH. It is nice to once again get familiar with the daily routine of the bands. 80 is hopping when I turn the rig on at 6 am local time. 40 seems to be active too. 20 opens a bit later, and I can hear stateside stations starting around noon local time. I really like hearing KZ1H up there in the high end of the 20 meter band -- I can hear him almost every day. Check out the ad for the HW 8 in a 1978 catalog. This must be a non-U.S. catalog because the ad brags of the HW-8's ability to "work the States." Not much astronomy this weekend -- Sabina and most of the rest of Italy fell under clouds on Sunday night. But I did catch a glimpse of Capella and the Kids.
January 2, 2010 Olive harvest in Sabina, Christmas and New Years in Rome. "What, no Klingon?" How's my whistling SSSS problem? DX on 20, HW8 QSO with KZ1H Auroral flutter on US stations W4OP: Homebrew Hero Softrock progress Linux woes 72 Part Challenge: "Stuck between best wishes and hugs and kisses!" Chinese Hamsat in orbit, with CW telemetry AA1TJ in CQ, and using diodes as audio amplifiers. Stradavari and Julia Child: inspirational late starters! Billy's RC plane QRSS: telemetry next? WSPR: 150K reports per day New issue of Hot Iron MAILBAG
This is just so good, I felt the urge to share it immediately with the SolderSmoke community. Thanks Tom, and Happy New Year to all!
Bill:
Happy New Year! I am yet another listener who discovered your podcast by accident and am now hooked. I also thoroughly enjoyed your book. Both take me back to the days of scrounged parts and burned fingers, building balanced modulators and an FM stereo transmitter that earned me an invitation to leave a great southern university.
To celebrate the new year, rising sunspot numbers, and your 120th podcast, I offer the attached photo of a Solder Cake. It features 120 rolls of 60/40 rosin core solder -- several brands and gauges. The cake actually weighs 123 lbs. because the roll holding the soldering iron at the top is 4 lbs. It has zero calories, but definitely contains lead! It should be baked at less than 370 degrees, or the icing tends to run.
Why would anyone have 120 rolls of solder? I don't remember precisely, but rumor has it that ebay and alcohol were involved.
73, and a wonderful new year to you and your family.
"SolderSmoke -- Global Adventures in Wireless Electronics" is now available as an e-book for Amazon's Kindle.
Here's the site:
http://www.amazon.com/dp/B004V9FIVW
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