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Junkbox Telescope Gallery

Some years back I posted Jeff Duntemann's Homebrew Radio Gallery, and for reasons unclear it's become one of the most popular pages on my site. (Tube construction may not be quite dead…) So a while back I wrote up and (almost) finished a page about all the various telescopes I've built out of junk since 1966. Longtime Contra readers have seen some of the photos, but a few are new scans of prints I've had in a box for decades.

Jeff Duntemann's Junkbox Telescope Gallery sat unfinished on a thumb drive for some months, until I finally bore down and finished it a few days ago. It's not a how-to; there has never been and will probably never be a better junkbox telescope how-to than Sam Brown's classic All About Telescopes, which is in turn a compendium of shorter booklets that Brown published through Edmund Scientific in the early-mid 1960s. $14.95 is cheap for a book like this. If you ever have the least inclination to put together a scope from scratch, buy Brown's book first.

The page is mostly a photo collection, with some odd notes on how I did what I did. Note well that you don't have to grind and polish your own mirror as I did. Ready-made 8″ primary mirrors can be had for $300 or sometimes less, and the rest of the scope can be, well, junk. Also note that I think Dobsonian mounts are silly: With a 2″ 45° street elbow you can have something approaching an equatorial mount if you live in the US.

Building scopes like this is mostly a lost art, and there are definitely advantages to scraping up the cash for a Meade or a Celestron. (Tapping in “M31” on a keypad is less messy than lying on your back in a cowfield and sighting the nearly invisible object along the edge of the tube.) But it's a good kid project, because when you're done you—and any involved kids— will know exactly how it works, and that's worth something all by itself.

Treasure Chest and Obama as Pettigrew

Even diehard comics fans have generally never heard of Treasure Chest of Fun and Fact—unless, of course, they went to Catholic grade school between 1946 and 1972. It was a comic book produced in Ohio for national distribution to parochial schools, and maps well to the era of Postwar Triumphal Catholicism. I was a grade schooler between 1958 and 1966, so Treasure Chest was always kicking around somewhere, along with Our Little Messenger, Young Catholic Messenger, and numerous other things that the George A. Pflaum Company of Dayton was always pumping out. I read Treasure Chest when it was handy, though I did so absent-mindedly and was never a big fan. The comic ran the gamut from preachy (always) to silly (often) and the quality was very uneven. The larger and long-running series were often beautifully done from a writing and art standpoint, though much of it glorified sports, which was a Catholic fetish at that time, in the hopes that young boys exhausted by sports will not go off by themselves somewhere and, well, you know.

I was chasing memories around the Web the other night when I discovered the Treasure Chest archive at the Washington Research Library Consortium. This is a wonderful thing, but for copyright reasons it only has the magazines from 1946 through the end of 1963, which is unfortunate for reasons I'll relate shortly. I remembered only three of the continuing series; the rest of it had fled my brain cells until I started skimming the archive. There were textual letters from some priest (probably advising young boys not to go off by themselves somewhere and, well, you know), illustrated lives of the Saints, and insufferable lectures by Patsy Manners on etiquette and how to throw good parties. (Mixed parties! No, don't read that! We don't do such things in Chicago!) It was a real and sometimes classic comic; if you read nothing else, check out Kidnaped by a Spaceship from 1959. If they ran more like that I might have been an enthusiastic fan, but no; most of what we got was like Chuck White and His Friends, which was about an older guy who took young boys off on wholesome adventures, I'm sure so that they would not go off by themselves somewhere and, well, you know. Funny animals were big, and for a bit of prescient comic surrealism (I flashed on Cerebus) skim The Bear and the Wicked Wainwright. (At one point the Wainwright calls the Bear a “base poltroon,” which became faddish on the playground for a few weeks, though I may have been the only one of us sixth graders who bothered to look up “poltroon.”)

If Treasure Chest is currently famous for one thing, it was for the 1961-62 series This Godless Communism, which still gets the lefties het up. I rolled my eyes a little then and still do; the problem with Communism is not its godlessness but the fact that it murdered a hundred million people in the 20th century alone. Treasure Chest understood its working-class Catholic audience and was completely comfortable with praising organized labor in one of its illustrated civics lessons. No contradictions here; being a liberal has not always meant being a Marxist.

And Treasure Chest was fundamentally liberal, as the term was understood in its time. If it has been famous primarily for This Godless Communism, it may soon become even more famous for something else: a 1964 series called 1976: Pettigrew for President! inked by the well-known comics artist Joe Sinnott. Again, it was a multipart civics lesson: A very slightly futuristic tale of how a candidate runs for President during the election of 1976—12 years in our future—with a little political huggermugger thrown in to keep it from being completely boring. (There were a few scenes with the SST, but in truth not a lot of other futuremongering. I was disappointed. What? 1976? No flying cars?) What none of us noticed at the time is that we never actually saw Mr. Pettigrew full-on. We saw his back, his hands, and so on, but never got a good look at him. I guess we all figured that it was about the process and not the man himself, and in truth we were all taken in and completely poleaxed when on the final page it was revealed that Timothy Pettigrew was Black! He got the nomination, but beyond that the story was open-ended. Here's what the final panel said, courtesy NPR:

“And so this man Pettigrew became the first Negro candidate for the President of the United States. He then went out across the land, this black man, to campaign for the highest office. Would he win? Well, the year was 1976. It was the 200th anniversary of the Declaration of Independence. Could he win? Well, it would depend in part on how the boys and girls reading this comic grew up and voted … it would depend on whether they believed and, indeed, lived those words in the declaration — All Men are Created Equal.”

Alas, I have yet to see the comic scanned and posted anywhere, since content published in 1964 and after is automatically still in copyright. (The earlier issues had not been renewed and thus passed into the public domain.) The best we can do is a YouTube video, of all things.

It's a measure of our progress that what was seen as an inspiring piece of comic book science fiction in 1964 smacks of tokenism today: So we should vote for him just because he's black? Or dare we ask whether he has a chance of running the country? (The country may end up doing a lot of growing up next year, heh.) And if you ever wanted to invest in comic books, now's the time to hunt down and grab Treasure Chest Volume 19, issues 11-20. They're going to be worth something soon, no matter which way things go this fall.

Odd Lots

  • Do not fail to read Bruce Schneier's latest short item in Wired, which is his simple demolition of David Brin's peculiar “transparent society” concept, which I first read of in his so-so novel Earth (1990) and thought was BS even then. Having no secrets doesn't help where the differential of power between two parties is high. This seems pretty obvious to me; I do not understand why Brin gets points for this “no secrets” notion of his.
  • Some of the worst horror films (as well as SF films and some westerns) can be streamed without charge here. Where else can you find “Attack of the Giant Leeches” or “Killer Shrews,” both of which I recall seeing on Channel 7 at 4 PM on Thursdays back 1965-ish. Even at age 12 I could roll my eyes and say, “Those aren't giant shrews. Those are dogs in bad shrew costumes.” But hey, that's what makes a B-movie a B-movie, right?
  • It may be clever, but can a gun this small really be deadly? (That is, assuming you don't aim it up your left nostril…)
  • This is freaking amazing: Images of a landslide on Mars, taken while it's happening. (Thanks to Pete Albrecht for the link.)
  • Jim Strickland pointed out a pneumatic tennis-ball based antenna launcher. We always used slingshots back in the day, and I have a Greenlee Cablecaster that was designed for dragging CAT5 over suspended ceilings via fishline, but something about the ball shooter is very appealing.
  • Glover Wright is bringing back Science Fiction Quarterly as an online pub, and it looks promising. I recall reading a few ancient issues of the original SF Quarterly pulps from the late 50s and was pleased, though the world and I were, um, at least thirty years younger then. The first issue will be out in March.
  • Gripe of the week: The keycap letters on my expensive Avant Stellar keyboard are decals, and they are already wearing off. It's only been a year. What's this thing going to look like after another ten?
  • Speaking of keyboards: I need a wireless keyboard for use while sitting on the couch and running photos or video clips on our big TV. The SX270 is under the TV in plain view of the couch. The keyboard needs to have an integral pointing device. (I prefer things like IBM's TrackPoint nipple to the ubiquitous scratchpad.) Anybody got any suggestions?

Fruit Wine and Pork Stew

Not much time tonight, but it's worth reporting a recipe that Carol threw together off the top of her head earlier today:

Pork Stew

Cut a two-pound pork roast (not a loin) into 1/2″ cubes. Sprinkle flour on a cookie sheet and then salt the flour. Coat the pork cubes with flour and salt, then brown them in oil. Add half a 750 ml bottle of some sweetish wine. We used Mountain Spirit Winery's Angel Blush, a fruit wine consisting of 40% apple, 40% pear, and 20% raspberry. Cover and simmer the browned meat in the wine while you cut up three Yukon Gold potatoes and two apples (we used Braeburns) into similar sized cubes. Simmer for three-four hours. It's not critical. Add water if the liquid level gets too low. The apples will break down and contribute some body to the gravy. Makes a lot; we should get three suppers out of it.

I tend to like sweeter wines, but I've never really warmed to fruit wine of any kind. I just finished the bottle of Breezy Hills Raspberry we brought home from Iowa (near Minden) last October, and it wasn't terrible but wasn't great. Fruit wines tend to taste yeasty to me, a little like beer, and I don't know if it's just a taste quirk of mine, or if I simply haven't tried any really good fruit wines.

The stew recipe was an experiment to see if stews (which can sometimes have a sweet edge to good effect) could be simmered in a sweet wine. The Angel Blush is a little too sweet to drink in any quantity, so we used it in the stew, and it worked very well. I don't think I would cook a darker meat in sweet wine, but for whatever reason, it went beautifully with lean pork. Give it a shot.

Odd Lots

  • I remember reading somewhere years ago that having a photo of a box on your Web store improves your sell-through of downloadable software, even if the product is never sold in a box and even if the box doesn't even exist. Anyway, here is a product that helps you create imaginary product boxes.
  • Here's another very similar product. We evidently have a small industry here that I had never heard of before this morning.
  • And yet another: This time, it generates a 3-D rotating video of an imaginary box!
  • After a little further research, I'm guessing that the “online affiliate marketing” industry is driving the imaginary box subindustry. On the other hand, the online affiliate marketing industry is itself imaginary, and basically a scam that labors mightily to stay just half a hair on the legal side of the razor. It's what the 419 scams would be if Nigeria had something like the FTC.
  • From Pete Albrecht comes a link to a video showing how well a 21-foot (!!) X-wing model rocket flies. (Flies? So-so. Dies? Spectacularly!)
  • Don Lancaster has a detailed article (PDF format) about why rooftop PV solar power isn't as big a win as everybody says it is. Definitely worth reading, and pay especial attention to the description of exergy, a concept I had heard of but not understood until now. As with TTL and CMOS logic, Don finally made it click for me.
  • Is Flash memory “write endurance” (i.e., the number of times you can change the state of a Flesh emmory cell) a serious issue or not? I always thought it was, but Eric Brombaugh (one of my EE friends who knows a thing or two about such matters) sent me a link to an article that changed my mind. If you're interested in Solid State Drives (SSDs) the parent page is worth a look as well.

The Friction Is In the Discovery

I don't buy a lot of music anymore, and in thinking back, I suspect that I stopped buying when I stopped listening to the radio. (I stopped listening to the radio because the stations play the same sixteen stupid songs every twenty minutes…forever. But that's a separate rant.) The tough part in selling anything is discovery—basically, getting the prospective customers to know that you exist—and it becomes a lot tougher when you slide from machine screws to wine, and incomparably tougher yet when you move from wine into the realm of art. Absent radio, I discover new music a lot less often. Here's a recent discovery tale that did lead to a purchase, and if I were the artist I'd be maybe a little annoyed:

Carol and I don't watch a lot of TV, but we turn on the Weather Channel before we go to bed to catch Local on the 8s, and then again in the morning over breakfast. The Weather Channel plays “smooth jazz” during its canned local forecasts. My affection for smooth jazz is sparse, albeit less sparse than my affection for what I call club jazz. No sax please; we're contrarians—I think I dislike sax music because almost everybody else worships it. A few mornings ago, I looked up over my Cheerios to watch Local on the 8s, and realized that there were no saxophones playing. Better still, it was not the usual mournful, shapeless noodling, but a purposeful, upbeat (nay, near-manic) piano piece. Two minutes later, the forecast over and the music cut short by yet another Mucinex mucus man commercial, I ran out of the kitchen to the machine here, muttering, “I gotta have that!”

Alas, the Weather Channel does not announce the artists on its forecast music, so I hammered out a quick email to them, after spending several minutes digging through their site looking for a contact link: Please, folks, what was the title/artist of the bouncy piano piece playing during today's 6:58 AM Local on the 8s?

I only half expected an answer, and was working on memorizing the piece so that I could whistle it to whomever I might know in smooth jazz fandom. But yay wow, by late afternoon, I got a nice note from a Weather Channel junior staffer who confessed that she didn't know precisely, but the February AM playlist was attached. And so it was: The email carried an Excel spreadsheet containing the titles and artists for 15 songs, one of which was by implication the bouncy piano piece. I just didn't know which one.

I had done this kind of detective work a time or two before. I first looked up the artists, separating the pianists from the sax maniacs. It came down to either Leo Tizer or Bradley Joseph. I went over to Amazon, looked up the artists, and started playing the samples for the album tracks named in the playlist spreadsheet. On the third try, I got it: Brandley Joseph's “Rose-Colored Glasses” (and Bradley himself) had been discovered. Ninety seconds later, I had purchased the track through One Click for 89c, and had a DRM-free MP3 in my music directory. Ninety seconds after that, I had his CD album (Hear the Masses) on its way. The friction was all in the discovery.

Amazon supposedly sells two million music tracks as unencumbered MP3s. I shop for music so rarely that I didn't even know this. I did know that Amazon has been selling PDF-formatted short stories (and other short textual works, including nonfiction) for a couple of years now, for 49c a pop. Alas, by the time I decided to apply to the program, they had closed it to new submissions, but the delivery mechanism is the same as for MP3s: If you have One Click enabled, you get the item in a few seconds.

I think Amazon Shorts may have been doomed because Big Name Writers would not sell unencumbered PDFs, and Small Name (or No Name) writers do not sell enough of anything to justify the effort it takes Amazon to vet them and post them. Or perhaps Amazon is simply migrating the program to Kindle. We'll find out eventually. The point to be taken away here is that we have digital delivery down cold. Discovery is fluky and always will be, especially for things like fiction, which (with vanishingly rare exceptions) you do not hear on the radio. Amazon can make the gumballs drop into your hands. We're still not sure how they'll make you want the gumballs, but tougher problems have been solved.

In the meantime, Bradley Joseph has another fan, and might have more if the Weather Channel would just put his name in the corner of the screen while they're playing his music over their forecasts. I hope he got some cash for the license, because not everybody is going to dig as hard as I did!

Open That Bottle Night

Last night was Open That Bottle Night, the annual event that Wall Street Journal wine columnists John Brecher and Dorothy Gaiter created almost by accident a few years ago. The idea is for people who have been saving a bottle of wine with emotional or historical connections to their lives to stop hoarding it, just open it, and enjoy it. It was a golden opportunity for us to pull out the dusty bottle of the Schlossadler Gau-Odernheimer Petersberg Dornfelder Rotwein 1994 that we had originally intended to open on our 25th wedding anniversary in 2001. The bottle has a peculiarly effective sort of self-preservation instinct: We forgot and left it behind in Phoenix when we drove to Chicago to celebrate our 25th in 2001. (9-11 was only a week before we left, and other things than wine were on our minds.) We then figured we'd open it on the 35th anniversary of our meeting one another in July 2004, but again we were in Chicago. The following year we figured we'd open it on July 31, for the 36th anniversary of our meeting, but were famously foiled by my flop into a patch of poison ivy. We then figured we'd open it for our 30th wedding anniversary in 2006, but by that time the bottle had gotten so far back in our memories that we clean fergot.

That bottle was a survivor, heh.

So a couple of weeks ago, while reading John and Dorothy's column in the WSJ, Carol looked up from the paper and said, “We have to open That Bottle on February 23.” This time for sure, Rocky!

And so we did. David and Terry Beers were here for dinner, and we cobbled together a Polish feast, with some kielbasa, honey millet bread, and cheese pirogi. Although I was concerned that the wine might not have survived (like all dornfelders it's fairly light, with only 9.5% alcohol) 14 years isn't all that long a time, and just as several people reassured us, the wine was unbowed.

What I did find remarkable was how indistinctly I recalled it. (We had bought half a case in October 1996, for our 20th, and I would think it would have remained clearer in my mind.) Dornfelders are almost invariably off-dry to semi-sweet, and this one is about as sweet as any dornfelder I've ever had. I remember it being a little drier, perhaps because I've had numerous drier dornfelders since then. The fruit was explosive, with some of the most intense black-currant flavor I ever recall in a wine of any stripe. It went well with the kielbasa, and the four of us had a wonderful evening talking about life, relationships, dogs, writing, ebooks, and ultra-mobile PCs. (It's that kind of crowd.) I don't recommend dornfelders to everyone—sweet reds bother a lot of people—but this one was a keeper, and if you have an open mind, sniff around the odd corners of your larger wine shops and try one.

Alas, we have no bottles of anything even remotely that old, and certainly nothing with that memorable a run of brushes with consumption. So next February we may just go eenie-meenie-mynie-moe and pull something from the rack. The wine is the thing, sure, but more than that, it's about friendship and having history together. This July, Carol and I will have known one another for 39 years, and we're pondering a whomper party somewhere in summer 2009. I guess it's time to shop for That Special Bottle so we'll have something to pass around in celebration of friendship, ours and that of all the many people we value in this beautiful and extravagant world.

Tabor Hill’s Classic Demi-Red

We brought a wine home from Chicago last summer that sat quietly in one of the top slots in our kitchen island rack, mostly out of sight and until a few days ago, completely forgotten. The wine is Tabor Hill's Classic Demi-Red. It's a $9 wine from Michigan, and I broke it out looking for something that would go well with a spicy (for us at least; read here: has some spices in it) chicken goulash that Carol threw together just for fun.

Yes, it's fairly sweet by wine snob standards, but it's less sweet than St. Julian's excellent Red Heron, and on a sweetness par with most white zins. It has the virtue of not being sour, as semi-sweet wines too often are, probably by imitating white zin. It's fruity and does not have the sour white zin ragged edge. The label calls it “soft” and I agree. No perceptible bitterness, and not grapey, though “grapey” is not a show-killer for me. (It usually means having a whiff of concord in it, which is not always a bad thing.)

It's a 12% wine and went down very easily, making a good complement to the goulash. I don't know where all you can get it. We saw it in several of the Meijer's markets outside Chicago, and I can only assume it's common in Michigan. I have yet to see it in Colorado, and we probably won't have it again until our next trip in.

Nonetheless, if you like sweetish wines, I call it highly recommended.

By the way, tonight is The Wall Street Journal's Open the Bottle night, and we will (finally!) be opening the bottle of 1994 Schlossadler Dornfelder that we failed to open for our 30th wedding anniversary back in '06. Maybe's it's vinegar. I don't know how well dornfelders age. But we'll let you know.

Odd Lots

  • From Jim Strickland comes this report of a new coinage. How many seconds did it take for you to get the joke? Did you get it at all?
  • Alas, neither the Death Star Grill nor the Darth Vader gumball machine made it past the first cut. Dayum. (Thanks to Pete Albrecht for the link.)
  • This, on the other hand, is a real product. (Again from Pete. Don't miss the video.) On the other other hand, if you have to ask, well…
  • Here's an interesting discussion on the economics of rooftop PV solar power systems. (Thanks to Frank Glover for the pointer.) As with a lot of posts like this, the real action is in the comments. Had we stayed in Arizona—and possibly built a new custom house there, which we were considering—I would have installed a system like that. Note that batteries are not necessary unless you're completely off-grid. (A lot of people still don't understand this.) The power companies are basically paying you for adding peak power capacity to their grid by reducing your monthly bill. Doesn't work well everywhere, but where it does work well (basically the Southwest) it will become a great deal cheaper over the next fifteen or twenty years.
  • Sometimes I can spot a hoax. Sometimes I can't. And sometimes I just can't decide. (I know enough artistes to understand that anything's possible.) So you tell me.
  • It's hardly new news, but I don't generally walk in those precincts: Romances represent 21% of the $6.31B print book industry. SF/fantasy comes in at $495M and mysteries are at a surprisingly low $422M. (Those are print book sales only. Ebooks not included.)
  • Chris Gerrib called my attention to a great rant by John Scalzi on what's still wrong with SFWA, which I still haven't re-joined, and may not until I know that Andrew Burt has removed himself from their environs to, say, Uranus. And even with Burt out of the way, I'd like to know what the organization thinks that it is, because I myself have never been quite able to figure it out.
  • The generally clear skies in Colorado Springs failed us on Wednesday night for the eclipse, and while we could tell there was a moon up there (and could tell that it was partially occluded) details were utterly lacking.

Review: Tom Igoe’s Making Things Talk

Triage is a harsh mistress. I started out in computing with the CDP1802, a microprocessor designed for embedded systems work (it was used on the Viking Landers!) and for all the software I've used and the code I've written since then, I miss poking wires in breadboard holes and hitting the trigger of a wire-wrap gun. There's only so many hours in a life, and embedded work has not made the cut.

That may change. Embedded systems tinkering is easier now. Much easier, and for a couple of reasons: 1) The processors themselves can be had on small boards with appropriate I/O connectors; you don't have to fool with loose chips anymore. 2) Development software is better, mostly because now there is development software. In 1976 I literally had to write binary code by hand. (F8 FF A2… Yes, yes, I know, barefoot and uphill both ways. But if you think I'm exaggerating, you simply weren't there.) And, the point of the current discussion, 3) there are books like Making Things Talk, by Tom Igoe. Wow.

The first time I saw the cover I was confused: It shows a stuffed monkey and the completely inane blurb, “Projects and ideas to create talking objects from anything.” I literally thought it was about fooling with speech synthesizers. But no: It's about networking embedded systems modules with technologies including Ethernet, USB, Bluetooth, and Zigbee. The microprocessor modules under discussion are the Atmel AVR-based Arduinos, augmented by a host of sensor modules and connectivity modules that can be breadboarded on the same 0.1″ spacing blocks we used to use in 1976. In a sense, we now have modules the way other people have chips. (And in saying so I am indeed just boasting.) We can raise our consciousness to the level of connecting functional blocks rather than individual inverters and logic gates. That is a very big win.

The book is patient (as good tutorials must be) and begins with probably the finest introduction to low-level networking that I have ever seen. If you are a software developer you will understand it; if you have no experience whatsoever in networking or programming, you may have some trouble. A good prerequisite text would be Tom Igoe's 2004 Physical Computing (written with Dan O'Sullivan) which focuses on the older Basic Stamp modules and their close relatives. Physical Computing introduces both electronics and programming to a degree that Making Things Talk cannot. That said, Making Things Talk presents examples using a Java-derivative programming environment called Processing, which is free and open source and much gentler conceptually than programming in raw Java or, merciful God help us, C. (Pascal would be gentler still, but as we all know, Pascal is a kiddie language that cannot accomplish anything useful. You must believe this. A C programmer said it. QED.)

Once the essential groundwork is done, the book teaches through projects, good projects that are mostly fun and in many cases even useful. The book explains how RFID tags work and how to read them, and how to read 2-D barcodes with a Web cam. The most fascinating projects are those that involve physical location sensing, using modules that perform infrared ranging, ultrasonic ranging, GPS, and “digital compass” modules, all of which made the robot guy within me itch like hell. We didn't have stuff like that thirty years ago.

Although it doesn't get a huge amount of coverage in the book, the XBee module (which implements a Zigbee data radio system) fascinates me: It's basically jelly-bean logic implementing a short-range mesh network, and I intuit that hobby robots of the future may well consist of swarms of semi-independent functional blocks knit together coherently through the Zigbee network protocols, under the control of a multicore master processor. And damn, I would love to build something like that.

Anyway. Here are a few additional observations on the book:

  • It has at least process color on most pages, with beautifully shot full-color photos on many of them.
  • The technical figures are abundant and very well done.
  • The type is very small, the margins narrow. This 425-page book would have been a 600-page book back in the 90s. My guess is that O'Reilly wanted to the keep page count down because of all the costly interior color. Note to my age cohort: Prepare to squint, or go get yer readers.
  • There is far less discussion on debugging than I'd like. Coding is easy—as is plugging jumper wires into breadboard blocks. But when something doesn't work the way it should, where do you start? The book is mostly silent on that crucial point.
  • In general, the book probably covers a little too much ground, and doesn't go for quite enough depth. Zigbee is subtle, and its subtler features are not explored here. This may not be a completely fair criticism, but it supports my conviction that you must be a journeyman embedded systems type to really get the most from this book, as a lot of the blanks you must fill in yourself.

Don't let any of that stop you: If you have some clue about embedded systems modules and want to learn embedded systems-level data communications, there is nothing like this book anywhere. And if I do decide to go back to embedded systems tinkering, this will be the book that pushes me over the edge. Not yet—I have a rocket or two to finish and a few other things to do—but soon, soon.

Highly recommended.