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Daywander

Jun 27th, 2010
by Jeff Duntemann.
3 comments

hatchetman.jpgWell, as a fair number of people have told me, the logo Carol and I saw the other day was the “hatchet man” icon of Insane Clown Posse, a hip-hop duo from Detroit that I’ve never heard and probably won’t. Key to finding the figure online is knowing that what he’s holding isn’t a map or a piece of paper but a hatchet. (In fact, it looks a lot more like a meat cleaver.) There’s also a girl-version of the icon, with a ponytail, but what we saw on the gate of a pickup truck was almost precisely what I show above left.

We had a relatively small gathering last night, but that was all right, as there were few enough of us to all sit on the two couches and talk about everything from dogs to SF to classic aircraft of the Strategic Air Command. We spoke of that lunatic Lt. Col. Bud Holland, whose lifelong ambition appears to have been to roll a B-52. (Detailed discussion here.) He tried, he failed, and you can see a video of the results here. Eric Bowersox and Sabrina Hoyt brought some Mountain Dew Throwback, made with real sugar instead of corn leavins’, and the original product artwork on the cans. There were intermittent thunderstorms all afternoon, but we had enough time between microcells to grill a batch of smoked brats and Ranch Food Direct burgers. By sheer coincidence both Mike Reith and Peggy Sargent brought cream puffs, and it had been so long since I’d had one that I’d mostly forgotten what cream puffs were. That memory came back in a big hurry, heh.

Alas, the thunderstorms prevented me from getting any Field Day time in yesterday, and with less than an hour remaining in the contest and yet another thunderboomer passing overhead as I write, I doubt I’ll get any time in this year at all. I created what I had hoped to be a low-profile inverted vee, and in truth, when I told people I had antenna off the back deck, several people looked and just didn’t see it, when when I was pointing right at it. It’s designed to be portable, and is attached to the deck railing with bungee cords. I’ll try to get a couple of days’ contacts with it, then roll it up and put it back in the garage.

There was more bear action yesterday. Late afternoon, our doorbell rang, and it was our new neighbors from across the street. Heather and Glen had gone for a walk with their two small boys, aged two and four, and left their garage door open. When they returned, sho’nuff, a bear was in their garage ransacking their garbage can. Heather asked to bring her boys inside, but about then Glen came back and said he’d driven the bear off by throwing rocks at it, after which it vanished up the street and ran between two other houses. (Glen’s an Army officer. Spend some time in Iraq and bears lose a lot of their mystique.) I’m guessing it was the same bear I saw yesterday about lunchtime, eating dog food down in our gully near our back door. It seems a little too comfortable with people and a little too willing to be out and around during the day to stay here, and if it comes back too much we’re going to have to put a call in and see if it can be relocated.

Lots of leftovers from last night, and I’ll be grilling Ranch Food Direct burgers again this evening if the rain will just stop for half an hour. The West is getting soaked this year. Our local reservoirs are full, and western Nebraska’s massive Lake McConaughy is refilling (after a 9-year drought that the doomsayers warned would be permanent) at a rate of two feet per week. When we first saw it we marveled at the broad sand beaches, which were not in fact beaches at all but recently exposed lake bottom. It was about 30% full when we first saw it several years ago. It’s now over 80% full and the water level is rising fast. (Note the end of the curve on the graph, and then see this graph to get a sense for the insane amount of water flowing into it this year.) We hope to take a long weekend up there before the summer’s over.

This coming week should be fairly peaceful. I intend to do some fiction writing and perhaps even finish an experiment I have on the bench downstairs, concerning how well IN23A microwave diodes serve as AM BCB detectors. What I know of detector theory tells me that such detectors should be socko. We’ll find out–that’s what science is for.

Odd Lots

Apr 4th, 2010
by Jeff Duntemann.
1 comment

Odd Lots

Mar 31st, 2010
by Jeff Duntemann.
2 comments
  • I’ve been thin on Contra entries this month for a number of reasons, mostly because I’ve been putting the bulk of my creative energy into finishing “Drumlin Wheel.” Nailed the first draft (after nine years!) about an hour ago. Originally scoped out at about 11,000 words (like “Drumlin Boiler”) it ended up at 14,500. As always, when something major emerges from my subconscious I tend to hate it for a couple of weeks, after which I can fix what’s wrong and like it again. More on this at some point.
  • While in Hawaii recently, we heard whale songs through a hydrophone that the tour boat crew had tossed into the water, and I immediately wanted one of my own. (We hope not to wait another five years to go back to Hawaii.) Here’s an article on how to make your own hydrophone, which is nothing more than a waterproof mic on a (long) cable.
  • I finished reading Fat and Cholesterol Are Good For You by Dr. Uffe Ravnskov shortly after we got back from Hawaii, and was about to write a review when I realized that Tom Naughton had already done it–and written just about what I would have.
  • Somebody put a window in the side of one cylinder of a 4-stroke engine, and took a slow-mo video of the action inside the cylinder during actual operation. An amazing thing, even though some frames are missing from the exhaust stroke.
  • Oh, I’ve seen sillier things than this…but not recently.
  • And finally, CNN reminded me that the original Xerox copier, model 914, was fifty years old yesterday. The article is marginal and doesn’t even include a color photo of the gadget, of which I repaired many many many between 1974 and 1977. There’s a better photo of the Brown Beast here, along with numerous other Xerox goodies.

Steampunk Home-Made Tubes…and Transistors!

Jan 15th, 2010
by Jeff Duntemann.
6 comments

tennis1.jpgWhile ragchewing with Joe Flamini earlier today, we got on the topic of whether or not it would be possible to make a usable transistor in your basement. It’s not a cakewalk, but a fair number of people have made their own vacuum tubes at home. I myself have made a sort of point-contact diode using a chunk of galena (lead sulphide) crystal and a piece of #44 wire–it’s what the old guys used to call a cat’s whisker detector. Like a lot of guys, I added a second whisker and thought it might become a point-contact transistor, but I didn’t know how to test it. (And that was in 1964.)

There’s a kind of early junction transistor called a “meltback” that starts with a small germanium bar. You heat one end until it melts a little, and as it hardens and recrystallizes after heat is removed, P-dopants gather somehow in the zone between the melted and unmelted germanium, and what results is an NPN transistor. I read years ago of somebody making meltback transistors in his basement, but I can’t find the reference now. I guess the hard part is just laying hands on a piece of germanium with both dopants in it. This article describes a number of ways that transistors are made, including the meltback method. None of them seem difficult from a lab technique standpoint, but there’s always the question of just where you get a little indium when you need it.

While researching the question I came across the Web site of H. P. Friedrichs AC7ZL, who wrote a book some years ago about making tubes and transistors at home. The book is called Instruments of Amplification, and used copies are available for about $25 on Amazon. I don’t have it yet, but I want to call your attention to the author’s online photo albums, which show some of the devices that he’s built. They’re beautifully photographed, and definitely show some steampunk influence. Here’s Album 1, and Album 2.

A fair number of people were stumbling around in the dark pursuing solid-state active devices as early as 1910; here’s a good overview. So not only was it possible for the Edwardians to make transistors, some actually came pretty close to doing it. The problem was not even access to materials–pure germanium had been available since the late 1880s–but simply that the physics was still obscure. A suitably intuitive scientist who understood electricity as well as it was understood in 1890 could have worked out PN junction physics. The fact that nobody did could have been simple bad luck: The right guy with the right background and the right obsessions working in the right lab with the right tools and the right materials just didn’t turn up.

While we talking steampunk, few are aware that a purely steam-powered biplane flew successfully in the early 1930s. It had a interesting characteristic: It was quiet. Internal combustion is nothing more than a continuous series of explosions inside a piston. Generate your pressure some other way, and the sound level goes way down. There’s some period b/w silent footage on YouTube. The engine could be quickly and easily reversed, though it’s not clear to me how valuable that would be in a biplane.

Steam-powered aircraft interest me because there’s nothing essentially electrical about a steam engine. In my novel The Cunning Blood I suggested that all aircraft on Hell (a prison planet seeded with nanomachines that homed in on and destroyed electrical conductors) would be either Diesel or turbojet powered, simply because I didn’t think you could make a steam engine that was both powerful enough and light enough to fly. I guess I was wrong.

Heh. I love to be wrong!

Odd Lots

Jan 13th, 2010
by Jeff Duntemann.
5 comments
  • We take digital clocks for granted, but this project may give you some perspective on just how difficult a challenge a digital clock really is. Absent integrated circuits, it takes over 1200 discrete electronic components to make a 6-digit digital clock. And you can get a kit.
  • Maybe RCA’s engineers are having a little fun with us. It’s hard to tell sometimes, but I still don’t understand how this thing is not a hoax. I maybe know a little bit about both RF power physics (37 years in ham radio) and Wi-Fi. If there’s a place in the world with enough Wi-Fi hotspots to make that little box generate useful power, please tell me where, so I can be sure never to go anywhere near it.
  • Several people have noticed that my author bio photo on Amazon has been replaced by someone else’s. Most oddly, the photo is of my old friend Jon Shemitz of Santa Cruz, who’s done some very good books on Kylix and .NET 2.0. I’ve been trying to get Amazon’s attention for a couple of weeks now, no luck yet.
  • Classmates.com did it again: They sent me an email asking whether I’d like to reconnect with a girl from my high school class. As I’ve said before, Lane Tech High was all-male until several years after I graduated, so there was no Teresa Mazzerelli in my class–nor does she appear in the alumni directory. One I could call a database error. Two I call fraud. Don’t give these guys your money.
  • Malt is my favorite ice cream flavor, but it’s very hard to come by. Several companies have offered it in the last ten or twelve years, including Meadow Gold and Boulder, but the flavor has always vanished after a few months. I guess I may just have to make my own.
  • Sprint may be partnering with Wal-Mart to put WiMax nodes on top of every single Wal-Mart in the country. This is not the first time I’ve heard this, and have reported on it before, but having had some experience with something a little like WiMax, I think it could be a huge moneymaker for Wal-Mart if they don’t let the control freaks at Sprint ruin it.
  • From the Words-I-Hadn’t-Heard-In-Thirty-Years-Until-Yesterday Department: bildungsroman, a coming-of-age novel. Why, then, does it suggest erecting a shrine to the Emperor out of cow pies?

Harry L. Helms 1952-2009

Nov 20th, 2009
by Jeff Duntemann.
6 comments

I got word the other day that Harry L. Helms W5HLH had died this past Sunday. Harry was a friend for over 20 years, and we met regularly at trade shows including the Borland conferences and ABA/BEA, just to touch base and trade ideas. He and I had a lot in common: We were both longtime hams, we both liked classic radio gear, shortwave listening, and publishing. (We were also within a few weeks of the same age.) He was the co-founder of HighText Publishing in Solana Beach, California, and the author of a lot of books worth reading, including Shortwave Listening Guidebook (1993), How to Tune the Secret Shortwave Spectrum (1981), Top Secret Tourism (2007) and Inside the Shadow Government (2003), which may be the scariest book I’ve ever read. He published Andrew Yoder’s Pirate Radio (1996) which is best-of-breed on the history of that insane little cross-current in the mostly placid waters of the radio broadcasting industry.

His passing was nothing out of the blue: He had blogged about his struggle with cancer for several years, and displayed a species of courage in the face of imminent death that I hope I can summon when my own time comes. His last months were spent in his home town in South Carolina, with his wife and family, and his dogs and cats all around him, and if we all have to make that final leap into the unknown, I’d be hard-pressed to think of a better way to do it.

Harry had a healthy scientific mind, and while not religious, he told me he was open to the possibility that death is not the end of all things. He enjoyed uncovering the hidden and the secretive and the overlooked (see Top Secret Tourism for a travel guide to all the places the government would just as soon nobody knew about) and I have an intuition that he was looking forward to seeing “what was out there.” In one of our last exchanges some months ago, I made an outrageous suggestion, about which I won’t say more unless something remarkable happens.

We’ve got his books, and for the time being, that’s remarkable enough for me. W5HLH DE K7JPD / TNKS GUD LK ES 73 SK.

Odd Lots

Nov 8th, 2009
by Jeff Duntemann.
1 comment
  • Watch out when upgrading to Skype 4: The upgrade installs a Firefox/IE extension called Browser Highlighter that slows the browser down significantly, and I sure don’t remember it showing me a checkbox to uncheck or in any other way refuse the install. This install-without-warning has gotten people more than a little het up. Like Skype, Browser Highlighter is owned by eBay and appears to facilitate online price comparisons. To get rid of it, execute the uninstaller via Start | Programs | Browser Highlighter. Don’t just disable it in the browser; it must be uninstalled from Windows like any app or it’ll just show up in your taskbar tray again when you reboot.
  • From the Words-I-Didn’t-Know-Until-Yesterday Department: An acnestis is an itchy place that you can’t reach to scratch. (Thanks to Larry Nelson for the suggestion.) I use a 24″ slide rule to scratch my acnestes. Very accurate; gets to precisely the right spot!
  • The Arrington Crunchpad may be in trouble. Dayum. I had high hopes for this one, not so much for Web or cloud work as for an ebook reader.
  • Here is a fantastic archive of scanned Radio Shack catalogs, browsable page-by-page. I had a lot of these from the midlate 60s to 1980 or so, and intermittently since. (Thanks to Bernie Sidor for the link.)
  • From Bill Cherepy comes word of a managed PC built into a network jack. It’s unclear how well this would run desktop software, but for cloud computing it could be useful, and in a cube farm setting would not be easily picked up and walked away with.
  • In addition to Green River and Diet Green River, there was at one time Green River Orange Soda, and Pete Albrecht reminds me that there was yet another (unrelated) Green River: The Whiskey Without a Headache. I’ll believe that when I feel it. (But I can’t stand whiskey, so don’t wait up for me to do the experiment.)
  • And if “whiskey without a headache” sounds a little unlikely, then say hello to the robotic cow rectum.

Odd Lots

Jul 5th, 2009
by Jeff Duntemann.
2 comments

* From the Words I Didn’t Know Until Yesterday Department: “Forcemeat” is meat ground sufficiently fine to make it cohere with a fat base, and mixed with spices and sometimes other ingredients before incorporating in patés, stuffings, and sausages.
* The Weather Channel is running saturation-level advertising for a “3D chalk” product from Crayola, which is apparently a selection of very bright, almost day-glow colors of sidewalk chalk, plus a pair of 3-D glasses with which to view your sidewalk artwork. Done correctly, the warmer colors seem to float above the sidewalk a little. It’s almost impossible to think of this product and not flash on the sequence in Disney’s Mary Poppins in which the gang jumps into Bert’s sidewalk chalk drawing.
* The venerable Alfred Morgan borrowed some of the circuits found in his boys’ books on electronics. I found the phono oscillator circuit from The Boys’ Second Book of Radio and Electronics in a 1943 Meissner data book, and now Peter Putnam sent me a link to a 1955 article in Popular Science showing something very close to the diabolical Geiger counter circuit that I tried and failed to build (out of the same book) in 1964.
* There are fake high-capacity USB thumb drives going around. (Thanks to Frank Glover for the link.) Nobody’s making 128 GB thumb drives yet (though they will eventually) so don’t fall for it.
* Also from Frank comes a link to an interview with Eric Lerner, the man who claims to have developed a new kind of fusion reactor he calls “focus fusion.” I’m not enough of a particle physicist to know whether this is a scam or not (though it sure smells like one) and I hope that my readers who are particle physicists can tell me whether the physics is as dicey as the business plan.
* Our long, long sunspot drought may be coming to an end. Spot 1024 is the largest seen yet of the new Cycle 24, and the largest sunspot seen in almost a year. I guess I better start shielding the fire alarm sensor wires, so I can get on 10 meters!

Odd Lots

Apr 23rd, 2009
by Jeff Duntemann.
1 comment
  • SRWare Iron was doing a peculiar thing: When I used it to view my junkbox.com main page, the title image was broken. This was not the case using IE, FF, or Opera. Nor was it true of the several other images on that same page, but only that big main one. An intuition led me to look up the name of the image file: junkboxmainbanner.png. I renamed the file “junkboxmain.png” (that is, removing the substring “banner” from the filename) and the image began rendering normally. I guess there’s a downside to adblockers as twitchy as this one.
  • From Bruce Baker comes a nice chronological screenshot survey of computer GUIs since the primordial Xerox Alto in 1973, up through Windows Vista and KDE 4. No judgements are passed on the products, and not much history is offered, but it’s unusual to see them all lined up in one place, and one definitely gets a sense for the way it all evolved, and especially for the immeasurable debt that Apple owes Xerox.
  • On a tip from Pete Albrecht, I’ve learned that the Progressive Insurance girl Flo and one of the Geico cavemen shared a scene in the short-lived 2007 TV sitcom Cavemen . Here’s a YouTube clip of the scene. This was sheer coincidence; the Progressive ad campaign did not happen for at least a year after that and Stephanie Courtney just happened to get the part. I tried to like the series and failed, but I’ll admit that it had some surreal moments, a few of which we evidently didn’t appreciate at the time. Now, cavemen ate geckos. (Cavemen ate anything they could catch.) Dare we hope…
  • Here’s an old article from Popular Mechanics on building your own Geiger counter. Michael Covington reminds me that there was a circuit in Alfred Morgan’s book The Boys’ Second Book of Radio and Electronics, though it had a peculiar power supply and didn’t work when I tried to build it in 1966. (I may still have the G-M tube somewhere, but I can’t find it and in truth haven’t seen it in decades.)
  • Yet another one, this time from Popular Science, March 1950.
  • Todd Johnson suggests using scrounged or surplus fluorescent lamp supplies from computer scanners for homebrew Geiger counters. I’ve got two defunct scanners on the woodpile downstairs, but if you don’t, Todd also sent along a pointer to a surplus source, for only $5.
  • Today is Ubuntu 9.04 day. It’s like the Day after Thanksgiving at Marshall Fields up there, so don’t expect much in the line of download performance. I’m going to wait for the dust to settle a little (and maybe for my assembly book to be done) but it will happen here sooner or later. If you want it, look for torrents. And come with a backpack of patience.
  • Do you have Linux running on an Intel DQ35 motherboard. If so, be careful.
  • Finally, this clever food hack reminds me vaguely of something. I don’t know what. That’s probably just as well.

Odd Lots

Mar 18th, 2009
by Jeff Duntemann.
3 comments
  • Back when I was in college in the early 70s, a woman friend told me, “The trouble with you, Jeff, is that you’re too damned happy!” Maybe this is the answer.
  • Numerous people have sent me links to “St. Patrick Drives the Snakes Out of Ireland” cartoons, and while they’re all good (use Google Images and you’ll see them) they’re not the one I remember, which I’m now pretty sure was published in National Lampoon circa 1974.
  • I misunderstood what my sister said about Crayola crayons in my March 13, 2009 Odd Lots. Crayola (once made by Binney & Smith, now part of the Hallmark empire) manufactures a line of washable crayons, and these are what Gretchen prefers that Katie have, given my elder godchild’s penchant for seeing all the world as her coloring book. The washable crayons have no particular smell to them, but the other day when Gretchen and Bill and the girls and I were in the Mount Prospect Hobby Lobby, Gretchen opened a conventional box of 16 Different Crayola Colors and let me sniff them. Yup. That’s the one. Perhaps some things really are forever.
  • I’ve thought that the name of the Sci-Fi Channel has been an embarrassment for 16 years. (Actually, so have most of their house-bred feature-length films.) But now, they’re changing their name to…Syfy. And adding professional wrestling to the lineup. The dork-in-chief over there says that he’s been trying since the 1990s to “…distance the network from science fiction.” Mission accomplished, dood.
  • From Baron Waste comes a largish drawn panel by Dusty Abell that somehow represents (as far as I know) every significant SF TV show to come out of the 70s. It’s a good proxy for how much TV you watched at the time, muddied by what you may have seen at cons in the middle of the night in intervening years. I can name perhaps a quarter of the shows represented, so I guess I wasn’t particularly tuned in. (I will admit with some embarrassment that the first whose title came to mind was “The Greatest American Hero.”) And although that little robot golem looks familiar, I can’t place the show that it was on.
  • From Pete Albrecht comes a page introducing the Decatron tube, which presents for display a circle of thirty neon-lit points that can be configured to move a group of three around the circle each time a pulse enters the circuit. (Follow the links for more detailed information, especially this one.) The tube “remembers” which group of points is illuminated, and so it can be used to build a decade counter, or a divide-by-10 prescaler for slower mechanical counters. Very slick, and reminds us that technology was perhaps a little more sophisticated in 1954 than we remember–because much of it didn’t sit in the corner of the living room.
  • Here’s a new kind of egoscan, at least for technical writers: Search Google Patents for your name. I’ve been cited 27 times in patent filings.
  • Rich Rostrom reminded me (after I reported close encounters with numerous tumbleweeds on the plains heading out to Chicago) that tumbleweeds are Eurasian imports that hitched a ride along with shipments of agricultural flaxseed from Europe in the 19th Century. Along with other things that we consider iconically American, tumbleweeds actually came from somewhere else. (I guess that makes us the Ecosphere of Immigrants.)
  • I didn’t know that Global Warming™ has made it impossible to build good violins. Um…I still don’t.
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