December 31, 2000:

I you haven't already, go see The Grinch. Carol and I went today, and although we may have been the last living beings to do so, it's worth checking. (And we had the advantage of seeing it in a nearly empty theater.) Seuss purists will frown, but hey, it's an entertainment, not a sacred writ. Turning a smallish kid's book that can be read to restless 6-year-olds in seven minutes flat into a feature-length film practically requires doing some damage to the original vehicle, and what was done makes sense in its own loopy way.

Jim Carey's Grinch looks pretty much as Dr. Seuss drew him, but has been fleshed out, and is now a grouchy eccentric living on the side of Mt. Crumpet, right next to the trash heap at the end of the line of Whoville's magical trash disposal pipe. Accompanied by his dog Max, he rummages through the dump, picking up what are for the most part discarded Who Christmas presents, and uses them to decorate and equip his cave. The Grinch, you see, is a techie, born different (green and hairy) and destined to be laughed at and excluded from things. Damn, I was there! (Wasn't green. Was hairy for awhile. No more.) The Grinch's inventions are wonderful, especially his kerosene-powered hovering rocket sled, stitched together with marvelous glee from Whoville's junk.

The Whos have changed quite a bit. Far from being the mostly faceless unflappable goodniks in the book, they are here made manic shoppers and fiercely competitive house-decorators, obviously into the season for what it can bring them. I'm not surprised they drove the Grinch nuts. During the Grinch's pivotal speech in which he denounces the acquisitiveness of the Who's celebration, even I twitched, and I'm not known for my Christmas excesses. So the story has taken a 180, in a sense: Instead of redeeming the Grinch with their singing, the Grinch redeems Whoville by taking away their junk for a while and demonstrating that they can be happy without it. Yikes! The poor nerdy Grinch is hilariously Who-brutalized in a couple of scenes, including one where he judges a fudge contest by allowing virtually every pointy-nosed Who in Whoville to shove multicolored fudge in his mouth. Perhaps they redeem one another—certainly, they deserve each other, and it's nice to see, at the end, that the nerdy Grinch gets the girl he wanted to impress in grade school.

December 30, 2000:

I got ambitious today, and went out in the garage and put a lightweight camera mount together so that I could shoot photos with the Digital Elph through my 10" F6.7 Newtonian telescope. What I got, after almost no trouble, is shown below. And this is through a telescope that is being heavily renovated, has a lousy focuser, an incomplete clock drive, and dicey balance. It was all a very simple, brute-force setup. The scope was focused for corrected vision, and the Elph was shooting focused at infinity, in black and white mode, with the timer enabled. I pushed the button with my finger (there is no cable release hole) and the timer let the scope settle down for ten seconds before snapping the shot. It worked very well. What fuzziness you see comes from the image moving slowly across the field of view due to the Earth's rotation—what the clock drive will eventually counteract. This shot was taken with an Ultrascopic 15mm eyepiece, giving a magnification of about 80 diameters. There was plenty of light, and in fact I'd like to have a faster shutter speed to reduce the light a little bit. (I took some shots at a lower magnification and they were terribly overexposed.)

Here's a picture of the scope itself, as I set it up this evening on the concrete pillar I poured about a year ago. (I work slowly sometimes...) The rod protruding from the tube is the camera mount. You can also see the finder scope support rings. The finder is not mounted in this photo. As you can see, there are some C clamps "assisting" the mount a little, since it isn't complete yet. Ditto the drive; there's a small aluminum handwheel where the drive motor needs to go.

December 29, 2000:

Getting the Digital Elph to take black and white photos was no big deal—just one menu option, and the option works well in macro (close-up) mode. Here's a good example. The gadget is a plate choke, which is about two and a half inches high, tops:

I didn't post the "big" photo as I did in yesterday's entry, since I don't want to push the limit of my Web hosting service with half-megabyte images. Still, I think you can get the idea. The problem is getting the lighting right, and I'm working on that, but the focus on the "big" image is almost microscopically sharp. The payoff here is that I may want to self-publish a book or a pamphlet about radios or telescopes or some other technical pursuit that involves small parts or other objects. Having a high-resolution black and white photo of some small object can make the difference between being understood and not being understood. I can't show you here, obviously, but my poor little HP Laserjet 2100M does a beautiful job reproducing the B/W photos that come out of the Elph.

December 28, 2000:

I'm nowhere near through the manual yet, but I've been able to take a number of amazingly good pictures with my new Digital Elph camera. For something so small, it's astonishingly capable. I was especially interested in its macro capabilities; that is, the ability to get right up to something small and take a good sharp photo. Here's an example:

It's a small audio amplifier built on a 3" square piece of printed circuit board, using a 6T9 triode/pentode Compactron tube. Consider this a thumbnail; click on the photo to download the full size image, keeping in mind that it's a 400K file.

I took this photo from about five or six inches away from the device, sighting through the LCD display on the camera's back panel. This is one deficiency I've discovered so far: The optical viewfinder does not correspond very well to the image that is actually taken. To get the photo framed correctly, you have to sight on the image on the back, in the manner of one of those old Graflex twin-lens reflex cameras that were so popular in the 50's. Here's another photo:

This is a close-up of the most peculiar 832A VHF power tube, a dual tetrode that was the little brother of the much more famous 829B/3E29. The tube is about 3" high, and this was taken from about five inches back. Lighting was a problem to some extent (I was just using available light out in the garage) but focus was not. Again, click on the photo to bring down the (much) larger full-resolution image.

December 27, 2000:

The press has convinced everyone that we're about to slide into a recession (meaning now that we probably will) and the layoffs are beginning. An interesting psychodynamic has been masked by the last three or four years of hyperprosperity: Companies want flexibility in staffing, and staff want job security. This disconnect is hidden while the economy cooks along and there are more jobs than workers, but when things turn sour, the employees that companies want to retain the most are the first ones to jump when their employer shows the least sign of weakness. This in turn makes managers hesitatant to be honest with their staff about the company's financial condition—which then makes the disruption worse when the pink slips finally appear.

I can see the sense on both sides. Staffers who sniff a recession will often jump to the strongest company they can find, even if it means taking a salary lateral or even a modest pay cut. This is especially true of people in areas where there are only a few major employers. The best people want to leave before the last boat is gone, lest they find themselves stranded without work in a suburb of Dubuque when the economy hits bottom. Managers respond that if they couldn't lay anybody off that they wouldn't hire as many people to begin with, which is true, and one reason that Europe has such high structural unemployment.

December 26, 2000:

Carol bought me something marvelous and unexpected for Christmas: An S100 Digital Elph camera, which is a 2.1 megapixel digital that measures 3 3/8" X 2 1/4" X 1 1/8". (I sure hate to use this ugly old simile, but it's about the size of a pack of smokes, as my old man used to say.) About a quarter of its volume is battery, and another significant portion is memory card. Where they fit the rest I'm not sure, but it has 4X digital zoom and 2X optical zoom, a flash, and a USB port, along with a digital video output port. The included 8MB memory card is pretty useless (it holds 4 shots at the camera's highest resolution) but you can get much larger cards, up to 48MB. The memory cards can be hot-swapped, so you can carry extras with you as though they were rolls of film, and suck the images out of the cards when you return home.

December 25, 2000:

I heard the bells on Christmas day,
Their old familiar carols play.
And mild and sweet the words repeat:
Of peace on earth, good will to men.

I thought how as the day had come,
The belfries of all Christendom
Had roll'd along th' unbroken song
Of peace on earth, good will to men.

And in despair I bow'd my head:
"There is no peace on earth," I said,
"For hate is strong, and mocks the song
Of peace on earth, good will to men."

Then pealed the bells more loud and deep:
"God is not dead, nor doth He sleep!
The wrong shall fail, the right prevail,
With peace on earth, good will to men." 

December 24, 2000:

The global warming crackpots are sabotaging their case by insisting that the real danger in unconstrained CO2 emissions is warming, per se. Weather and climate are a great deal more complex than that, and when it gets to be ten below zero in the Midwest at the beginning of December (as it did this year) people roll their eyes at the notion of global warming, and assume it's just another left-wing nonsense obsession. There is danger in adding too much CO2 to the atmosphere, but the nature of that danger is violent and unsettled weather all the way around—wind, temperatures, precipitation, everything. Disturbing climatic equilibrium could in fact cause an ice age. We just don't know. It's a pretty sure thing that the recent spate of killer hurricanes is not an accident, but people won't connect that with "warming" and nobody's calling much attention to the issue except the usual crap about melting the polar ice caps.

December 23, 2000:

My early experience with Mac OS/X (through my book acquisitions work at Coriolis) suggests a path by which Apple could indeed take over ther world: Stop manufacturing hardware! People have been telling them this for years, and they keep ignoring the advice. If they do this long enough, it'll kill them. (And our growing tech slump could be the mechanism to do precisely that.) OS/X is basically the Mac user interface (flawed but still excellent—get a second mouse button, guys!) overlaid upon BSD Unix. And BSD Unix is very good as OS kernels go—better than Linux, and much more reliable than Win2K, if not as clever in some areas. (BSD is a kernel. It is not a complete operating system in my view. "Operating" includes a modern UI. No UI, no OS. Linux is struggling with this same problem, though not struggling hard enough in my view.)

Apple keeps ignoring how Microsoft got to be where they are: By piggybacking on other people's hardware, not insisting on doing all the hardware themselves. The iMac is a nice piece of work, but nothing all that astounding—and today, even Swiss Army Knives are coming out with translucent pastel polycarbonate handles, sheesh. The Cube, however, is appalling; an industrial designer's silly masturbation in acrylic that is a mighty step backwards from what computer hardware ought to be: Out of sight and for the most part out of mind. A cubical box requires significant space on your desk. You can't put anything on top of it, and its footprint is almost equal, functionally, to a mini-tower, in terms of keeping you from doing anything else with the space. An ideal computer would be a flat rectangle that could be placed beneath the monitor (the old NeXT pizza box was a marvelous idea!) or behind it.

December 22, 2000:

About twenty years ago, (I would guess 1980 or 1981) four years or so after my first modest adventures in personal computing, I started speculating on the future of these damned machines. I wrote big chunks of an SF novel (never finished) in which people keep their machines clipped to their lapels, and talk to them. Keyboards and displays were not integrally a part of the machines; they were just dumb household gadgetry, ubiquitous, cheap, and stupid. A high-bandwidth infrared link allowed the lapel computers (which I called "jiminies," after Disney's cricket-on-the-shoulder conscience from Pinocchio) to communicate through whatever keyboard and screen (or other suitable device) they were within a few feet of. People spoke to them, and they spoke back. For private communication in the absense of a handy keyboard, I had people use something I called a "bongo bar" in their pockets, on which finger pressure in various combinations encoded certain characters. A pea-sized transducer inserted in the ear echoed the characters encoded on the bongo bar. That much troubled me; it sounded too difficult to use. But I never thought of anything better, and in truth, that's a major hassle today, even as we grow ever closer to developing the jiminy as I originally envisioned it. Can you imagine a roomful of people all talking to their jiminies at the same time? Of course you can—it's no different from a roomful of people all talking on their cellphones at the same time, and you know how pleasant that is.

I honestly didn't think it would be this soon. (The story was set in the year 2052.) But I'm seeing great gadgets like the Handspring Visor, which has an expansion slot into which you can plug a voice recorder, cell phone, or GPS receiver, among other things. We're most of the way there, and if we hadn't set the arbitrary price ceiling of about $400 on these things, we'd be even further along. I'd gladly pay $1000 for something that had enough functionality. Give me another day or two to think, and I'll describe here what functionality that would be.

December 21, 2000:

I journeyed deep into darkest Rich Guy territory today, hunting the elusive Taster's Choice Hazelnut Instant Coffee, which has recently become extinct at local supermarkets like Albertson's and Safeway. I have drunk nothing else at breakfast here at home for a good many years, and I don't want to have to stoop to brewing coffee in one of those ridiculous 2-cup Mr. Coffee mini-machines. My search took me to AJ's, a sort of grocery/deli/latte shop/gift emporium famous in parts of Scottsdale for catering to people with way too much money and way too little to do. Sure enough, I bagged several jars of Taster's Choice Hazelnut almost immediately, and lingered to gawk at the rest of the wildlife. Egad! 34 different varieties of balsamic vinegar! Vegetables whose names I can't pronounce! Organic sheep cheese!

Wow. I was in awe of the liquor section, which included (in addition all to the usual suspects) a pear cordial with a real pear knocking around inside the bottle. How they did that is a question I would like to ask but do not reasonably expect ever to be answered. Another species of German booze is shipped in a little glass simulacrum of a black 55-gallon petrochemical drum. I culdn't read the label, but doubtless it was high octane. Oddly, they did not carry Leaping Lizard Pinot Noir, which I have heard good things about but cannot find, and suspect may be an urban legend.

In the locked glass liquor cabinet was a bottle of something brandy-ish with a price tag (unless it's a mistake) of $1650.00. The scary thing is that there was absolutely no dust on it.

December 20, 2000:

After doing some poking around, I discovered that Visio 2000 can export a drawing as a VML (Vector markup Language) file embedded in an HTML frame. VML is something I'd heard of some years ago and completely forgotten about: It's a portable, device-independent vector graphics system specifically for posting line art (rather than raster art) on the Web. The downside, of course, is that not every browser can display VML files. IE5 can, but Netscape 4.7 cannot. (I haven't installed Netscape 6 yet so I'm less sure about that.) Visio appears to finesse this by exporting the drawing not only as a VML file but as a GIF as well, and depending on the browser that requests the file, renders the file that the browser is capable of displaying.

I exported the schematic for the one-tube radio (see my December 17, 2000 entry) as VML, and it looks superb in IE5--and precisely as you see it below for Netscape, since what you see below is a GIF. What is less clear, alas, is how to embed that VML cleverness in an existing HTML page. That's my research task right now. That, and another item: The new vector art specification from WWWC: Scalable Vector Graphics (SVG). It looks to be identical to VML, but of course it's too new for Visio to understand it yet, so even if the new Netscape supports it I have no way to produce the files.

December 19, 2000:

Here's an interesting and perhaps slightly loopy conjecture that came to me while I was heading down to Safeway for some Cepacol. It could be that our nation's mood is so strange now, so dark and fatalistic and twitchy, because...we're bored. We have it very easy compared to any prior generation (here in the United States; I'm not talking about other nations now) and we are running out of things to strive for. Striving (what in older times might have been less delicately called struggle) is much less a part of our lives than it was forty or fifty years ago. This is a new thing, and something at serious variance with our past. We evolved as merciless, furious strivers; killer apes with a versatile brain and a flexible physical shape. All challenges we identified fell before us. It took us a million years or so (depending on where you drawn the line between ape and human) but we licked it. All of it. For the vast middle of the bell curve (and the high end, for which this has long been true) living is objectively easy. We work fewer hours to earn a car, a TV set, or housing than we did in mid-century or any time before. I know this seems counter-intuitive, but every time somebody publishes the numbers it's right there. Living is easy—and it's killing us.

With organized religion fading into the mists of history (alas) we take most of the meaning in our lives from what we do, and what we do seems ever more loosely connected to survival. Sure we get paid, but where do many of our more obscure jobs actually fit into the big picture? What are we struggling against? I'm not sure I know—unless it's a suspicion that the game is over, and that the next step is for the board to be cleared and put back on the shelf. Why else all the armageddon angst and apocalyptic nonsense that besets us? We're not even less moral than we used to be, in the historical sense of morality, which includes much more than just sexual probity. Sexual cruelty used to be acceptable, as long as it took place within marriage. No more. What matters today is the cruelty, not the sex, and that's a different issue altogether, and a better deal of the cards. My reading of history tells me that we are a better, kinder, more generous and more educated people than we have ever been before, yet we see ourselves as doomed dissolutes, albeit for different reasons depending on our political leanings.

My explanation? We're bored. We've answered all the easy questions and most of the hard ones. What remain are challenges so tangled and obscure that we can't even define them. I've tried to understand the bounds of today's physics, and I just can't do it. Complexity theory suggests (nay, proves) that many things are simply unknowable. Social problems defy analysis, and politics even prevents the research we need to do to begin to address them. (Ever tried looking for research into why some people are poor and others not? The research doesn't exist. The universities won't do it, and will howl down any researcher who raises the question.) So ordinary people turn away from striving at the unwinnable, and sit in front of their home theater systems wondering why they're not happier.

Utopia is a paradox. Only in striving are we happy, and striving, for most of us, is becoming a thing so routine and disconnected from meaning that it ceases to be striving at all.

December 18, 2000:

December 17, 2000:

I drew up the circuit for the 3V4 regen, and here it is. Sorry about the fuzziness. It looks way better in Visio, but despite my protestations for years, Visio (now owned by Microsoft) has never created a plug-in or any other useful mechanism for publishing Visio art on the Web. Creating good technical art for the Web is a remarkably persistent problem. I could do it in Flash, I guess, but that's shooting gnats with a Howitzer. I don't need animation—just a widely-supported static vector art format. None is in sight. (Take note that I said widely supported.) So we're stuck with cruddy GIFs and JPEGs and everybody loses. Sometimes I think the whole Web ought to be redesigned, or at least rethought from the browser perspective...but I started out talking about one-tube radios.

This should be enough to give you some concept of what it is, though if you're utterly new to this business you might have some trouble figuring out how to build it. The tube could be either a 3V4 or a 3Q4, and a 3S4 might work. (Haven't tried that, but it looks good on paper, heh-heh.) The 3V4 and 3Q4 are electrically identical, but the tube elements come out to different pins. This means you have to choose a tube and wire the socket accordingly so that only one or the other can be used. Here are the pinouts:

December 16, 2000:

December 15, 2000:

I was at Safeway today, picking up some odds and ends, including a light bulb for my drill press (40W appliance size) and a small bottle of Bailey's Irish Cream to put over ice cream. I'm not much of a drinker; booze for me is mostly a dessert enhancement, though I've become fonder of dry red wines as I've progressed through my forties. While I grabbed the Bailey's I noticed a bottle I hadn't seen before: Ke Ke Beach, which is a greenish cream booze thing (will the sophisticates in my audience throw bricks at me if I call it an aperitif? Probably...) that tastes like key lime pie, complete with a hint of graham cracker. I bought it, and found it excellent over plain vanilla ice cream after a home-made meatloaf supper. Interestingly, the stuff is imported from the Netherlands. One has to wonder how they know about key lime pie, but y'know, it's a global society these days.

December 14, 2000:

Stopped in at Comp USA to get some Christmas presents for the nephews this morning, and actually took a look at some of the new Mac hardware. I'd heard about the Cube but hadn't seen one close up, and I will say I was impressed by the look of it, and by these $1000 Harman Kardon transparent acrylic speakers you could get to go with it. Now, I'm not nearly hip enough to own a Mac, and I will not use a machine that does not have a 2-button mouse. (Selection and context...that battle's over, guys. Give up already and add a button to your damned mouse!) I do think, however, that the new Mac laptops look a great deal like toilet seats, and there was a time in my life (long before the era of personal computers, actually) when that would have been a strong vector in the plus column. No longer.

December 13, 2000:

Celebrated my return to (more or less) normalcy today by actually putting real clothes on and going out to dinner with Carol. I don't know if any Contrapositive Diary readers are local to Phoenix, but we found (by accident) a brand new Greek restaurant at Scottsdale and Pinnacle Peak Roads. Eleanna's is in the space formerly occupied by the Saguaro Grill, which had been for its lifetime of six or seven years a diffuse and inconsistent eatery, trying to be sophisticated without committing to any sort of food genre. The only really stunning thing Saguaro's ever had was its three mushroom soup, and they abandoned that after their first couple of years, the fools. After that we more or less stopped going there unless we were late getting out and couldn't get into anyplace else nearby. (I loathe waiting to get into restaurants.)

Eleanna's has been open only about three weeks, and haven't even gotten their wine list together, and has a number of regular entrees not yet on the (preliminary) menu. Still, Carol had a stunning moussaka, and I had strip steak with Greek rice. The steak was melt-in-your-mouth tender, the rice quite different, somewhere between jasmine and basmati, with some Greek spices. I'm not much for moussaka, but I tasted Carol's and it was very good. (Eggplant R not us, for the most part.)

December 11, 2000:

Definitely better today, and I cut my painkillers down from two to one every five hours. I actually managed to read and do other intellectual things all afternoon, without any recognizable dip into a state of artificial stupidity. I can feel the incision a little, but not enough to bother me, and the tradeoff is definitely a good one.

This adventure makes an interesting contrast to my experience in January 1978, when I underwent almost the identical surgery (for an inguenal hernia) on the other side. Back then, I was in the hospital for three days and three nights, and for the first two days was getting a shot of morphine every six hours. Needless to say, I was in an opiate haze just about all the time, and recall (dimly) laughing at reruns of The Dukes of Hazard on the hospital TV. There had been much preparation back then, for which I had to check into the hospital the night before: An enema (yukkh!) and a complete shaving-cream-and-razor scalp-job on my crotch, courtesy a big (male) nurse, that left me looking like a nine-year-old. The anaesthetic (which I think was sodium pentathol) caused lingering chaos in my nervous system, and I recall waking up confused and slightly paranoid. Worse, it caused my bladder muscles to spasm, and when I went the entire first day without being able to pee, had to endure the additional indignity of a catheter. I ached under the incision for about ten days afterward, irrespective of pain pills. The food, furthermore, was lousy.

Way different now. I checked in at 10:15 AM for surgery scheduled at 11:30 AM. I shaved my own crotch with something resembling a dog clipper, and was told I only had to shave the area under the hernia itself. No enema. No special scrubbing of the area with antibacterial soaps. They put an IV in my arm (doing a pretty good job as IVs go—I've had some bad ones!) and wheeled me into the operating room. Nobody told me to count back from 100. There was no "here we go!" announcement or anything. I recall seeing them positioning these big round lightning fixtures over me, and then my next recall is waking up in the recovery room. No paranoia, no confusion, no pain. The post-op nurse took my vital signs, talked to me for a few minutes (probably as a means of evaluating my mental state) and then started shoving my sweats back on me. In a couple more minutes I was in the transport chair heading for the door, and they were wheeling my cart off for the next body on the assembly line. I had no trouble urinating once I got home. I've been a good boy and haven't pushed the envelope in terms of moving around, and I've had no significant pain. Carol's been feeding me home-made chicken soup and abundant love.

December 10, 2000:

December 5, 2000:

December 4, 2000:

I've been fooling with radios since 1963, when I was 11, but if you ever decide you want to try some of the things I've been talking about here this week, the first thing you should get is T. J. Lindsay's book How to Build Your First Vacuum Tube Regenerative Receiver. (The link will take you right to the publisher's site. It isn't available on Amazon for some reason.) The guy writes beautifully, and the book is one of the best and most detailed accounts of radio building I've seen in modern times. (Most other books about building tube radios are from the tube era, pre-1960, and call out lists of parts that are largely unobtainium.) The parts are available from Antique Electronic Supply, though you can cut costs by haunting a few hamfests. Either way, it's a cheap diversion compared to skiing or going to rock concerts. The most expensive thing, actually, aren't the tubes at all but the "B" batteries. (The tubes cost between $2.50 and $10.00, depending on which one you use, and are by no means scarce.)

December 3, 2000:

Problem number 2 on my ailing one-tube radio is that the circuit I used in building it demands a set of magnetic headphones with much higher sensitivity than the ones I have. Back in the 1920s and 1930s, loudspeakers were a bit of a luxury, and most people listened to the radio with headphones. These phones (called "cans" by radio nerds of the era) used extremely fine wire to create a magnetic field that induced vibrations in a thin soft iron membrane. The more windings of that thin wire, the more sensitive the headphones were. Now, the headphones I have are WWII surplus, and while they're well-made, they were not designed for use with the crude 1-tube radio designs that were popular in 1930. They were created for use with multi-tube military radios, and were built for ruggedness, not sentivity. So they don't create a very loud signal with the 1-tuber I put together ten years ago.

December 2, 2000:

I spent a little time with my barely-functional one-tube radio (see my entry for December 1) and found more than one thing wrong with it. Problem one is an interesting history lesson: I had the wrong voltage on the tube filament.

History lesson? Indeed. Back in the 1920s, when electricity-in-the-wall was far from universal (especially in rural areas) many radios worked on batteries. A tube radio needs at least two separate power sources. One supply (called the "A" supply) heats the tube filament until it glows orange-hot, like an incandescent light bulb. The other (the "B" supply) is used to apply electrical charges to the plate and the grids, to make the tube work as it should. The "A" supply had to provide a low voltage at a fairly high current. It was typically a single lead-acid storage cell, which could be charged from a wind generator or even a hand-cranked generator. The "B" supply, which provided a high voltage at an extremely low current, was usually a non-rechargable dry battery, which lasted a fairly long time and was simply thrown away when exhausted.

The voltage of a single lead-acid storage cell is 2 volts. The early battery-operated tubes for "farm radios" (as they were called) were designed to use lead acid cells, and thus required 2 volts to light their filaments and get those electrons jumping. Later on, lead-acid storage cells fell out of use (they were messy, and could produce explosive hydrogen gas if overcharged) and dry cells were used to heat radio filaments. Dry cells produce the familiar 1.5 volts that flashlight batteries (which are dry cells) provide today. So a second generation of tubes was designed to require 1.5 volts to heat the filaments.

December 1, 2000: