Kerbal Space Program + DayZ = ...Firefly?

Beside DayZ, I've recently started playing Kerbal Space Program. It's a game where you build rockets and send little green men off into space to land on their Mün and other planets in their little solar system. The physics engine lets it be moderately realistic in its behavior, enough for a game anyway. The build system is simple enough that a mere mortal can deal with it, or a rocket person who doesn't want to deal with lots of niggling details because nobody is paying them to do this.

I wrung the heck out of the demo version before I bought the full version. There are some significant differences between the two, aside from the obvious lack of features. For one thing, the simulation in the demo is more forgiving than the one in the full game. The full game does have the advantage that the simulation is more "fine grained" than the demo, though. This boils down to meaning that you have to pay more attention to how you build and fly your rockets in the full version, especially the large ones. The demo is more "gamey", in that you can slap together almost anything and get it into orbit. The full version requires a bit more thought and testing.

Recapitulating History

Since the demo's parts are similar to early NASA parts, I decided to get started by just putting together some simple tests to learn about building rockets in KSP.

My first was a capsule with parachute recovery (there's no other capsule or recovery system in the demo, so every flight is a "manned" flight.) I put this on top of a stack separator and a short tank with a large engine on the back and some fins for a bit of stability. I was worried that it would be too short to be dynamically stable along its length, that it would pitch or yaw wildly, but I decided to throw caution to the winds and launch it just to go through the process of getting something off the ground.

The real thing version of where I started in KSP

In spite of a lack of any control system, it flew just fine. It was about a 10 minute flight, surprisingly long for the amount of propellant, I thought. This basic configuration, sans fins, became the core of my next step--build a capsule and service module style combination that I could put on top of different boosters.

I added a dynamic control wheel system and some RCS jets to fill it out. Later, when I tried to use the RCS jets I learned that I needed to add RCS propellant tankage, too. It added a lot of weight, but at the end I had a solid core to build around for an orbital system.

This went on top of another stage separator, a taller tank, and another large engine for another suborbital test.

Mercury Redstone Suborbital Launch

That flight also went well. The fins of the first flight had been removed, and I decided to see how much stability I got with just the reaction wheel system and no fins on the booster. One thing that I missed immediately from the construction information was the lack of a display of the center of pressure on the craft. A basic measure of stability is where the CP sits with respect to the center of gravity (CG) of the craft. CP needs to be behind CG, and the greater the distance between them then generally the more stable the craft will be in the face of perturbations.

The other thing I missed was the lack of a sequencer to control the craft. It's a game, they assume that you want to "fly" the craft. I'm an instrumentation and controls engineer. I expect to build a solid program to get the craft to where I want it, then sit back and let it do its work. A sequencer is sort of a computer that looks at inputs from control instrumentation--acceleration, altitude, etc.--then does certain things at certain times--adjust valve settings, thrust vectoring positions, engine cutoff, etc.

That way you can let the sequencer manage engine throttling on the basis of altitude or velocity, engine shutdown on the basis of same, staging, and firing of the new stage (through that stage's control system.)

In KSP, there are a sequence of events set up linearly that are activated by the space bar. Engine activation (throttling happens elsewhere), stage separation, parachute activation (deployment is controlled by the parachute itself, which deploys as a drogue at high altitude then opens fully at about 500m.)

It more or less works, but having to "fly" each craft gets tedious for me. I'm of the school of aerospace engineer that feels the job is done when the vehicle gets off the ground. Then you just sit back and chew your nails till your bit completes its mission sequence.

Ascent to Orbit

The next step was adding some more power to the booster to get enough velocity for orbit. Given the sort of downrange distance I got with my suborbital vehicles (I flew 3 suborbital flights to different altitudes and downrange distances to get a feel for the craft and the controls), it wasn't hard to get a "seat of the pants" feel for what it would take to stretch the craft for orbital flight. Since the game doesn't give you much in the way of real numbers, that's about all you'll get. The "empirical method" rules here. But since it's just a game, it's not a surprise or much of a problem--I'm just used to having numbers for planning.

I added a second stage between my service module stack and my first stage stack, then added a couple of strap-on boosters to the first stage. Since I hadn't sorted out the sequencing of engines on the first launch, the strap-ons ended up being my first stage, rather than a "stage 0", with the core stage only firing after they burned out and were dropped.

I'd already noticed that the game's world behaves pretty much like our own world. It rotates the same direction, for example, so pitching over to the east would be the most efficient path to orbit. I fired up the booster--fortunately the strap-on boosters had enough thrust to get the whole stack of the ground--rode them up to a decent altitude, staged, then started tipping over to the east.

I took it slow on the tipping, since the whole rocket was so heavy that I wanted to make sure I got enough altitude. As it was, I rode the core stage up, staged, then continued the pitch-over to the east under power the full time. I know it's probably more proper to get the apogee high enough, shut down, then fire up again for a circularization burn at apogee, but I wasn't sweating that at this point.

Having only limited data on the main screen meant popping back and forth between the main screen and the map screen to check my trajectory. I wasn't sure if the game world had the same acceleration due to gravity as Earth, so I didn't know how much I could tell by my altitude and ground-relative velocity (and it bothered me that I didn't have a radar altimeter or some such to know my distance above ground, too. But that really bit me later, when I got to the Mün.)

I did manage to set up a decent orbit, and, yes, with a plenitude of propellant. I would be able to go home again. I played around with raising and lowering the orbit.

And here's where KSP gets really cool.

The immediate display of effects of acceleration on trajectory in the map window is really neat. It's easy to see what happens when you accelerate at different points of your orbit. It also gives players the chance to get stuck in orbit, revealing a bit of physics about energy use. And, even more significantly, changing orbital inclination.

One of the things that irks me is the common perception of "space" being like one big room, where everything that's "in space" is together. It's often presented this way in the simplified presentation of general media, and those people who don't have any direct contact with space work just don't know any better. They see the Hubble Space Telescope as hanging right off the front porch of the ISS, with all the spy satellites, weather satellites, commsats, etc, all right there in a row.

Now, every time I hear someone ask why the astronauts at the ISS can't just grab the Hubble and fix it, or why a Shuttle sent to repair a Hubble can't just ditch out to the ISS if something goes wrong, I'll wish that I could sit them down with a copy of KSP with objects in the respective orbits and let them find out through personal (non-lethal) experience why this doesn't work.

Back to my orbit. I didn't know what my parachute could deal with in the way of incoming velocity, so I decided not to come in from the higher orbit (about 400km), but returned to a lower orbit of about 90km before doing a re-entry burn.

The parachute held up fine. In fact, I learned that the system could deal with returning from orbits beyond 500km, but it was having trouble reducing velocity enough from around 750km. I didn't pancake any spacecraft, but I don't think I'd want to try a direct re-entry from 1000km. I don't know if the game engine does enough simulation to cause the heat shield on the capsule to fail, either. In general, I didn't push it.

I flew several more orbital flights, with minor tweaks to my vehicle design (like having the core booster fire at launch along with the strap-ons). I used different techniques for getting to orbit, in one case going straight up until I had an apogee of 500km, shutting down, then tipping to the east and firing to circularize at apogee. It worked just fine. I also did the routine of going a bit to the east, raising my apogee to about 90km, shutting down then firing a second burn at apogee to circularize. It may have been more fuel efficient than going straight up before circularizing, but it wasn't as easy to fly.

I picked 90km as my altitude just because that's the simulated altitude I've used on numerous test programs to test equipment in space-like conditions of atmospheric pressure (or lack thereof.) I've used other targets as well, like 75km, but I went with 90 because I wanted a little room. And, I was glad to see that KSP seems to pretty well mimic Earth so that I can use familiar numbers like these.

Final Thoughts

KSP should be played in schools, for credit. I would like to think that it can be used without taking away the fun, and that kids could be induced to set objectives for themselves similar to actual space program objectives (rather than just blowing up little green Kerbal people or ramming them into the ground at supersonic velocities.) The game has tremendous potential for teaching, in a "seat of the pants" way, information about ballistics and orbital mechanics. Then, when these subjects are encountered in math and physics classes, the concepts will already be familiar.

While on Facebook, there was a little game someone started of asking what you'd get if you combined the two computer games you were playing presently. In my case it was DayZ and KSP. I figure mixing zombie apocalypse with rickety build it yourself interplanetary space flight gives something like a Firefly game (Reavers=zombies in this case, in case that's not obvious.)

Commercial Spaceflight Isn't About Sending Fatcats to Space

I've seen a fair bit of "hate the rich" sentiment toward various "space tourism" ventures out there, such as Virgin Galactic's White Knight 2, XCOR's Lynx, and other development efforts toward reusable suborbital spaceflight. I feel this is driven by the usual specious reports by the media about space tourism and seat costs in the range of hundreds of thousands of dollars to drive the class warfare point home. Naturally, the first image that will come to someone's mind when seeing these reports is some overstuffed fat cat buying themselves a $200,000 joy ride at the expense of others.

The fact is, a point has been missed here. Space tourism is the economic model that's being used to draw investment for this work, but it's not the reality of where this work is going. In order to get money to do something new, without a proven business model, you have to build a business model from scratch. This means finding something that will presumably pay the bills and earn enough to pay investors a return at least as good as an investment in another proven economic activity, such as investing in a restaurant or manufacturing. In fact, the return needs to be better, at least on paper, to induce investors to take the risk of not putting their money into something proven.

For reusable suborbital launches, the case was made using space tourism. That's because none of the other potential uses is really well known, but a unique luxury offering could be pretty well characterized, and counted on to deliver a return.

But the real value in these quick trips to space lies elsewhere than in joy rides for someone with $200,000 burning a hole in their pocket.

It's Like a Reusable Mercury-Redstone for Suborbital Research

The Next Generation Suborbital Researchers' Conference is one group that's excited about the prospect of cheap suborbital flights. Currently, the overall cost of a sub-orbital flight on a sounding rocket is about $3.5M. The costs to the users are less, because much of that costs is subsidized by NASA, and by sharing of launches between institutions. It costs each institution about $50,000 to $500,000 per launch with somewhere from half a dozen to a dozen institutions sharing the costs between themselves. This gives them the chance to launch about a half a cubic foot to a cubic foot of payload on a short flight on a rocket. It will experience at least 25Gs of acceleration, with shocks of double that or more. Nobody can ride along, so the success of the flight will depend on the researchers' ability to automate their payload (adding considerably to the costs of building and testing the payload before flight.)

Flight on one of the new commercial launchers will cost the institutions about $50,000 to $400,000 per launch. They get to send a person to operate the experiment, and likewise to experience the ride, if they choose. They may also buy a package where they send their equipment, which will then be operated by a space tourist paying their own way who has been trained to operate the experiment, or the package may be activated by the spacecraft's crew.

The commercial space operators are already putting together special deals for the space researchers. They can buy into multiple flights at discounted rates.

Plus, their payloads can experience flight at human comfort levels, 3Gs or less, with controlled temperature, air, etc. This results in far less cost. The same instrument package used on the desktop at the university's lab can be the same one sent on the flight. It doesn't have to go through vacuum testing, extensive testing of the automation under different conditions, hardened against high shock loads, etc. Standard safety design and testing for not bursting into flames and filling the cabin with smoke will still be necessary, but that's a big step down in cost and effort from what's required for a sounding rocket flight. That drops research costs even more.

Another important point is that these flights will be far more available than sounding rocket flights. NASA launches somewhere around a dozen sounding rocket flights each year. The commercial flights will be more frequent, and easier for an institution to get a payload on board, deal with schedule changes, and so on.

Teachers in Space
Another purpose of the new commercial "tourism" flights is to send the sort of tourists I think most of us would want to send. Teachers in Space is a program that can't wait to use commercial spaceflight to send teachers into space with student research at all levels of education. Speaking as a part-time teacher myself, I can say that it helps the students a lot to hear about science and spaceflight from someone who's actually been involved in it. If we have a growing cadre of science teachers who can start a statement to students with, "When I flew in space...", work alongside them on projects they're building that will actually go into space, it will bring a sense of reality and engagement to their education that's so hard to get otherwise.

Other Desirable Space Tourists

There are plenty of other people we, as a society, would like to see get a chance to experience space travel. Make A Wish Foundation flights? Rewards for science fairs? Small companies doing their own research to compete against larger ones? There are many, many uses for these vehicles that have nothing to do with the ultra-rich burning off spare dollars.

Opening Up Space

That just happens to be the easiest way to show that there's a potential profit at the end of the long development process for those who invest in the companies making this happen. So don't be fooled by reports making the commercial space industry out to be nothing more than a new form of luxury for plutocrats. This is about giving little people the access to space that's so far been limited to governments and richer institutions. This is the same sort of revolution that we got with the microprocessor, which brought computers into our homes then into our pockets. Once upon a time, the computer was known to the average person as a tool of oppression. When your bank or government told you that their computer said you owed them so much money, you were stuck fighting a battle against the authority of a tool you didn't have. When we got our own computers, we got the power to tell them back, "Well, my computer says..."

Now, we're on the verge of having space access be democratized in the same fashion. Virgin Galactic, XCOR, and Blue Origin are not the end of this particular road, any more than the first heavy, balky, difficult to build and use microcomputers from before 1977 were the end of the process of democratizing the computer. But if early public sentiment had risen to kill off the early small computers as nothing more than toys for the rich, where would your tablet and cell phone come from today?

Be glad the rich are there, willing to buy tickets for a space adventure. Because they're there, the way is being opened for your kids and their teachers, their work and research.

In the words of Alan Stern, "The access revolution is about to happen. When these guys are flying all the time, and you can fly an experiment over and over and over and get different data sets all the time, close the loop and fly an experiment the next week and the week after, I think we're going to see the best applications be things we haven't thought of yet, because we're kind of looking at it through old eyes." (Aviation Week, June 17, 2013, "Suborbital, But Reusable" reporting on the 2013 NGSRC.)

Why Electronics Took Over the World

How did we end up in a world where computers are everywhere?

Originally, we had vacuum tubes as electronic components. Each of these has to be hand-made. When you consider that even the most basic computer, about the power of a programmable calculator, requires about 4000 electronic switches in it (including some basic control, memory, and interface circuits), you can see that needing 4000 hand made parts is going to get expensive. And that's before you wire them together into a working computer. It's like having to hire a team of scribes every time you want to get a new book.

Each of those tubes is like a decorated capital drawn by a scribe.

Transistors were a big step forward. Transistors aren't made one at a time by hand. Packaging them involved some hand work back when they were new, but the guts of them were produced en masse. Making transistors was like printing a sheet covered in letter "B" so that you could cut them up to have a letter B to stick wherever you need one. Similarly, transistors are made in a large group, which is then cut up into individual transistors then packaged for use.

So why not print the equivalent of a small piece of often-used text, rather than cutting it up into individual letters? This is the basis of the integrated circuit. It was another step forward in reducing the cost of electronics manufacturing. The first circuits were like having commonly used words, in complexity. Over time, technology advanced to allow more and more sophisticated circuits.

Eventually the circuits got more and more complex, and more useful. Building a computer got to be about as complex as creating a book on a typewriter. That means it took patience, and skill, and it was still expensive, but not nearly as expensive as hiring a team of scribes.

Each integrated circuit has from a few to as many as a few hundred transistors on it at this point. Building a basic computer circuit could be accomplished with a couple of hundred ICs.

The next step was a big one. Integrating the entire guts of a computer onto a single die, then printing them not one at a time, but by the tens then the hundreds at a time.

In the mid 1970s enough transistors were printed together, in the right circuits, to make a basic computer. When added to some memory (which was another technology that had recently benefited from the improvements in integrated circuits), a few ICs for control and for interfacing to the outside world, a complete computer could be built out of a handful of integrated circuits. Like my MAG-85 computer project, which uses about 10 ICs to build a basic 70's style computer.

But that wasn't enough. It was enough for calculators and very simple computers that require someone with a high level of skills to get the most out of them. If we'd stopped there, only very technical or very driven people would have computers. We had to increase their complexity to make them more capable, and easier to use.

Since then, we've improved our "printing processes" to allow us to produce integrated circuits that contain not just a few thousand "switches", but billions. Your computer, cell phone, or tablet contains the equivalent of billions of vacuum tubes. And yet, those billions of sub-microscopic electronic switches all together require less electrical power to operate than one single vacuum tube. They also generate less heat.

If we put the entire world population to work building electron tubes as fast as they can, we couldn't produce enough tubes to reproduce the computing power of a single cell phone in a year. In part because we couldn't build tubes that can switch as quickly as the transistors in a cell phone.

Imagine building a few billion of these, by hand. Image courtesy RJB1.

But the computer in the heart of that cell phone is one chip that was printed alongside hundreds of others just like it in a mass production process that's very similar to printing. Many of today's computer chips literally cost less to make than a printed magazine or book. Far less, usually.

This triumph of manufacturing, reducing electronics to a simple, inexpensive, high volume printing process, is why we have computers everywhere from our cell phones to our irons and dishwashers. They're cheaper to build than the parts they replace.

Have a look at a current computer chip sometime. Inside it are several billion man-made structures. You could look at them with a microscope if the top were removed, but you would only see patterns, not individual elements. The individual elements are too small to see in visible light now.

There are several billion man-made things in this image.

Ted Nelson's Computer Lib 40th Anniversary to be Honored at Chapman University

I forgot to mention an additional item in my post on meeting Ted Nelson. Chapman University will be honoring the 40th anniversary of the publication of Computer Lib on April 24th-26th, 2014, presumably at Chapman's campus in Orange, California.

Here are images of the flyer (once again, apologies for the fold. I put it in my hip pocket since I wasn't toting anything else to carry things at the time.)

Lee Felsenstein at Homebrew Computer Club Reunion

Lee was the MC at the main part of the club meetings back in the day, and he reprised that role on the night of the HCC reunion. He was also the designer of the computer in that day that I most desired, the Sol 20 Computer. I loved that system--the look, the keyboard, its operation.

Image by cellanr

There were just two things you wanted to know about the Sol to make life happier: Build the fully expanded system right at the outset. Opening up the heart of the system to expand it later was a major PITA. The other? Use someone else's disk subsystem. Though with the information available today a Helios disk subsystem could probably be made to work.

I still have the sales brochures for the Sol 20. I pull them out every now and then to drool over them again. Part of it is nostalgia, but part of it is the great design itself. Actual Sol 20s sell for more than I can afford, but perhaps I'll build myself a look-alike system from sheet metal and walnut wood sometime, anyway, and print up a nice black name badge.

I still have an Osborne 1 computer. This one is one I got only relatively recently. It is pretty well maxed out on upgrades (disk upgrades, video upgrades, etc.) and is a pleasure to use. It's not as pretty as a Sol, but I enjoy showing it off in current day computer classes. The kids love it--especially the floppy disk drives and the tiny screen. But...they get hooked on Zork.

Lee Felsenstein Today

In our conversation last Monday, Lee showed me a project he's working on today as an educational tool. It's a programmable logic simulator, targeted at middle school students. What Lee showed me was a pair of printed circuit boards that have captive fasteners to clamp them together around a plastic matrix. The matrix holds surface mount diodes, which the students can place into the matrix to program it. In essence, it's a 16 by 8 programmable logic array that is programmed through physically locating the diodes.

OK, I know that sounds totally abstruse to many of you, so let me tell you what makes this a great idea, and why your middle schooler ought to know about this stuff even if you've gotten through life without having to so far (assuming you don't know already).

The core of computers are built out of logic circuits. The memories feed the logic circuits with data (in current designs--it doesn't have to be that way though it's presently the assumption), in essence, the programmable logic is the complement to the memory. This analogy of the logic and memories being complementary components of a computer holds on many levels. It's possible to build logic out of memories--I've done it--but it's not efficient.

Initial education in logic circuits can be accomplished with a simple breadboard and some logic chips. A few AND chips, OR chips, NAND chips, inverters, and so on. Add some resistors and LEDs and the kids are off and running. For a little while. Once they master this, and understand what's going on, they immediately start expanding their ideas.

Then a problem hits. More chips and more wiring between them mean more complexity, and more difficulty in realizing their ideas.

At this point, it's possible to introduce them to programmable logic devices. Teach them that the logic functions they had in the ICs live inside the PLDs, and that they can program the devices rather than run wires. The problem is that this is a big, big jump up in abstraction level, especially for a kid in the middle school age bracket (which is the perfect age to introduce this stuff, which I'll go into later.)

Whereas Lee's invention maintains a physical element. The programming is accomplished by manually placing diodes into a matrix, rather than typing characters on a screen then punching the 'program' button to dump it to a Flash PLD. This keeps it from getting too abstract, encourages experimentation, and maintains the hand-on element that's necessary for students in the 9-13 years age range.

Building Blocks of Electronics

Electronic logic is building blocks. Your kids play with building blocks, right? They start with simple structures to learn how to build more complex structures. Before long, they can use every single piece they've got building large, complex structures. Once the individual blocks and a few simple ways of interconnecting them are understood, they can take off and make great big projects that reach to the ceiling.

It's the same with electronic logic. It's a collection of simple building blocks. The problem is, the complexity of assembly is a little greater. Enough that once you get past a certain level (I'd say 20-30 ICs), it gets progressively more difficult to implement your ideas. The ideas out-race the ability to construct.

This shouldn't be an obstacle. The ideas should be allowed to continue to grow, without removing the physical aspects that make the activity interesting.

The Lee Felsenstein Magic

Lee has hit a sweet spot here. With all the excitement about the Raspberry Pi (which I will save my criticisms of as an educational tool for a future article), Lee's project should have that sort of excitement going for it. This is about students building their own processor. This knowledge is important. This is what the people who caused the microprocessor revolution used to cause the revolution in our lives. This is the knowledge that put a CPU in your telephone, your oven, and your iron. This is what tunes your radio.

Assembling a processor from random logic is a huge project. Yes, people still do that (I've even build a very, very simple one from racks of relays, myself, under cover of testing those relay racks and their support wiring after installation.) Building your own processor with a PLD is a lot easier, once you understand the building blocks.

Lee explains himself well on his project page. Have a look. I will be following the progress of the project.

And I'm really glad I got a chance to meet up with Lee again after all these years. He was one of my mentors and inspirations in my youth, just as he describes those who mentored him. It seems to be a common thread that those of us getting older want to assist the younger generation just as we were assisted when getting started in technical pursuits (as hobbies--the jobs came later.)

And if you're raising a kid--don't just foist off software on them as something to play and "learn" with. Software isn't reality. I've designed any number of computers on paper and in software, and then go on to build far fewer of them. Because software and paper aren't the real thing. The real thing has all sorts of little niggles and oddities that you'll never learn about in any way other than doing the real thing. Teach your kids to solder, use solderless breadboards, and use real components at all levels of complexity. Don't try to do too much at once, start with kits then move your way toward recreating circuits on breadboards then to soldering them on prototyping boards.

But do the real thing. Right alongside your other crafts projects. Because electronics is just as much a craft with some useful products as is crochet or embroidery (both of which I do) or quilt-making or sewing (which some of those close to me do). And most of all, have fun!

Old Magazines: Living in the Past...and Present

Last week I was speaking at the Nevada County Astronomers, an astronomy club I'm in that I really enjoy a lot. Our President, Dave Buchla, happened to decide to clean out some old magazines he had in boxes at his house, and brought in a bunch of old copies of Sky and Telescope magazine from the 70s and 80s with a few other magazines from the same time period thrown in.

Well, I've got my own collection of S&T, I have a six foot tall book case that's over half full of them dating back to about 1979, when I first subscribed. But Dave had a bunch of older ones, most of which I remember reading in the library, before I had the money to have my own subscription. So I snagged a healthy sized pile of those.

Today I picked up the first one on the top of the stack next to my easy chair, and started reading. Honestly, I wasn't sure quite what to expect from reading a magazine over thirty years old, no matter how rosy my memories of it might be. It turned out to be much more than a simple sentimental journey, though.

The Future, From the Past

The magazine happened to be the March, 1979 issue of Sky and Telescope. The beautiful image of Jupiter on the cover drew me to it immediately. On the contents page I learned that this was an image from one of the Big Events of my youth, Voyager 1's encounter with the planet.

A few pages in I stopped my page-flipping at an article on mutual occultations of the planets. The headline included "1557 to 2230". Well, I figured I'd take a look at the chart and see if there was anything coming up now based on thirty-some year old predictions.

Unfortunately, the closest was not until 2065. So thirty years wasn't enough to catch up with the material of the article! A figure on the opposite page illustrated an event that's a bit closer, though, in 2037--a near miss of an occultation. So I dove into the article itself. Thirty years hasn't taken anything from this article. It's as timely today as it was back in 1979.

Dang, I thought, that's why I loved this magazine so much back then.

What Ever Happened to MIRA?

Moving on, I next paused at an article titled "Making it in Monterey". I wondered if the article was about something in Monterey, CA, not too far away from us here in the California foothills. Plus, I end up in Monterey about once or twice a year because we have family there. The word "Cleveland" in the caption of one of the photos confused the issue for a moment, but a quick scan of the start of the article confirmed that Monterey, CA, was indeed the place the article was discussing.

The article describes an effort to found a private observatory by a number of astronomy grad students back in the 70s. The article was very interesting, but the whole time I read it, I couldn't help but wonder what had come of their efforts. Being three decades into the future, I was able to go straight from the article to the internet to get an answer as to what happened.

Well, their daring escapade came to a happy end, at least from today's perspective. The observatory is still in existence, they have managed to construct their hoped-for site at Chew Ridge, and they have numerous public events. It's all on their website,
mira.org.

What a nice way to end the article.

So Much for the First 20-Some Pages

So now I'm about 25 pages or so into the first magazine from a stack that's about a foot tall. Already I've learned more about what's going on in astronomy today than I expected from a stack of 70's mags. I rather more expected to relive some past moments in the way that the "25, 50, and 100 Years Ago" column in S&T does each month, but with a bit more than the paragraph or two they reprint from each issue there.

Things like this are why I wish I could go to something like Google Books or the sites of the magazines themselves from the past (where they still exist) and sift through the old issues of all the ones I enjoyed back when, or the ones I missed out on.

New Call Sign, New QSL Card

I'm afraid I didn't care much for the Extra class call sign I got from the sequential call sign assignment. It was AG6HU. Before it was assigned, I saw on AE7Q's site that I was likely to get a call from the range AG6HT through AG6HV. I would have been OK with HT or HV, but I was hoping I wouldn't get HU. The call sign is funky enough with the AG prefix, but with an HU suffix there's just nothing there to love.

I tried, I really did. I tried coming up with interesting phoney phonetics for it ("higher up", "hugely unpopular", "hic up", etc.) What really sealed that call's fate for me was when I tried telling it to people. It took a minimum of three tried to get it across, even when using the International Phonetic Alphabet. That's bad.

So I applied for a vanity call sign. I didn't rush right out, though I didn't dilly-dally, either. Knowing that I wasn't going to stick with AG6HU meant that I wanted to get a new call before establishing much of an identity with that call. I spent a lot of time thinking about what I'd want that'd still be fun to have 20 plus years from now.

Since retrocomputing and microcontrollers are both hobbies of mine, the call W8BIT seemed appropriate. That's what I put at the top of the list, and that's what I got. W6CPU and W6TTY were high on my list. I didn't realize it when I applied, but another ham applied for W6TTY a few days before I did, and got that assigned during the 18 day waiting period for my new call (not that it mattered, since my first choice was available, but an example of a good reason to have more than one choice and be prepared to not get your first choice.)

Another one that would have been a lot of fun is KO5MAC, since I'm a fan of the COSMAC microprocessor (the RCA 1802.) It's a bit more specialized than simply "8BIT", so it ended up as a lower preference. Beyond the first three choices I listed, I didn't worry much about the order of the other calls I put on the list relative to my preferences. Any of them were better than AG6HU, and I pretty well expected that things weren't very likely at all to go past the top three. KO5MAC would probably have been my fourth choice if I had arranged them. It's an awfully fun call sign, just like the 1802 is a really fun chip.

I considered having a call with my current favorite microcontroller referenced, the Atmel AVR, like, say K6AVR or W6AVR (no idea if these are in use or not.) But that seemed potentially even a bit more narrow than the COSMAC reference, especially when viewed from the perspective of 20 years from now.

I got my new call sign on the 4th, I'd already figured out what I wanted to do for my QSL card. I got 100 of them printed up today. Here's what it looks like:



Ready to Go, Almost
On the more practical side of amateur radio--making actual radio contacts--I'm still moving things forward. Yesterday afternoon I replaced the towels stuffed in the window where the antenna cable comes through with a purpose-made wooden feedthrough. It looks a lot less "redneck" than the towels stuffed in a window casement.

Unfortunately, I don't have a good ground to the transceiver in its temporary home yet. I'd hoped to have time to pull that in yesterday but time ran short. But that's next. I'm not too worried about the ground when I'm just listening in, but before I key the mike I want to have a good ground on the radio's chassis. Then I'll be ready to jump into 40 meters, and possibly 15 meters.

I've been listening in a lot on 40 meters over the past week, and I'm starting to get a pretty good feel for the band. Like what frequencies folks are using pretty commonly, what sort of traffic is going on when (daily nets, some of the weekly nets, and so on.) So I'm pretty confident I won't seem to be a complete and total lid when I do key up. Though I'm prepared to make _some_ mistakes, it's part of the learning process.

Then the next major step is to clear out my corner of the garage, put in an AC/heater unit in the wall, a raised floor, and a bit of insulation. A few more touches like a mecca ground plate and feedthrough panel then I'm ready to put in shelves and furniture.

Somewhere in there I want to get or build a decent morse key or keyer. All I have on hand right now are a couple of ones of about the quality that were in kid's science kits 30-40 years ago.

So long as my current antenna keeps me going, I'll just go with it until the new radio shack is done before hanging up a new multiband antenna. A G5RV has been highly recommended to me by at least two hams. I've got a good idea of where a full size one would go on my property, and I'm looking to see if I can fit in a double-size one at right angles, more or less, to the first. That'd (hopefully) get me on the 160m band, too.

Lots to do, lots to do. In the meanwhile I'm going to grab my HT and make some contacts on 2m simplex.

73

Repairing the "Unrepairable" Microscope

The school I teach at has a small number of microscopes used by our science classes. I also use them once a year for a lesson where I bring in a bunch of microcircuits made visible to let my students see what's on a chip directly. I also bring in a wafer and some dice (the microcircuit variety, not the Yahtzee variety) for the kids to see and handle.

The exhibits themselves range from a 1959 transistor with the top of the can cut off to reveal the chip and a 1965 dual op-amp similarly prepared to a 1st generation microprocessor to late 80's memory circuits. All together I have about six to eight things I can put under the microscopes that would be interesting to look at.

Since I've been with the school, one of the microscopes has had a label on it reading "Broken, Save for Parts" on it. Since there are only six microscopes, including this one, it means I have to spend time in class changing over each scope from one object to another. Fortunately I've gotten good at talking while focusing a scope and shifting the light and indicator around to the best position. But it would be awfully nice to have at least one more scope. Recently another of the scopes got damaged, reducing us to only four scopes. This is really too few, especially for our science classes.

I Can Fix That

Our science teacher found out I work on optics (I build telescopes as a hobby, in addition to my work with sensor systems professionally.) She asked if I'd be willing to take a look at our newly broken scope. I agreed, and suggested that I might take a look at the "parts only" scope as well, since neither of us knew what was wrong with it.

The office staff let us know that the other scope had been declared "unrepairable" by a scientific instrument repair service that had looked at it several years ago.

When I took a look at the "unrepairable" scope, the optics appeared to be in perfectly good condition. The adjustments and controls were likewise all in good condition. All I found was that the light built into the base did not turn on. I had a light handy, for my own scopes I prefer a light that isn't built into the base, that way I can just grab another light if one of the bulbs burns out when I'm in the middle of a job. More than half the time I'm looking at something opaque anyway, and when I do look at translucent samples I use a mirror as often as I use a lamp for a backlight.

I opened the base to the "unrepairable" scope, wondering what would prevent the light from being fixed. Perhaps a small fire from a prior fixture?

Since When Is A Bulb Replacement "Unrepairable"?

When I got inside there was nothing worse than an empty light socket. The previous light had burned out, been removed, and not been replaced. I could see why, in part. It was an odd sort of bulb. The base style is the same as that for an automotive type "1004" bulb. It's a bayonet mount with two contacts at the tip of the base rather than the usual one. The designation is BA15D. It's an unusual type of bulb, especially for 120V. They run from about $5 to $35 depending on how specialized your supplier is. But they're not unavailable, by any means.

Still, they're hard to come by for people used to picking up light bulbs at hardware and grocery stores, so I decided to replace the base with a more common screw base. A standard medium size screw base, as used on most incandescent lamps around the home, would be too large to fit in the microscope's base. A small "candelabra" base would fit handily, but I wanted to make sure it'd be easy to get lamps in the right range of brightness. Candelabra base bulbs of up to about 15W are easy to come by in a size that would fit. But above that they tend to be the larger "flame" shaped bulbs in the 25 to 40W range, which wouldn't fit properly.

So it came down to an "intermediate" size screw base. Bulbs for these are common at hardware stores and such, as "high intensity" lamp bulbs (in 40W), and as lamps for vacuum cleaners, appliances, and such. 20W to 40W are common.

You Can Get the Bulb, But Not Its Base

Now the problem was finding such a base. I checked several hardware stores and lighting stores, with no luck. They all sold bulbs to fit an intermediate base, but no actual lamp bases in that size. I checked Radio Shack, just on the off chance, and my prejudices about their current parts stocking were confirmed. I even considered using the halogen lamps with the loop and straight leads on them. While the lamps are readily available, once again the bases are not.

I went to several stores and looked at cheap lamps, looking for one I could cannibalize without paying too much for the privilege. No luck, the LED lamp rules there, and none were suitable for a microscope. Neither the light pattern nor the size would work.

Finally I tried yet another hardware store while I was in another nearby town. I was ready to give up on intermediate size and go with candelabra, and hope to find a 20 or 25W bulb to fit. They had a single bulb wired fixture with a candelabra screw base. It looked perfect. The fellow minding the shop floor mentioned a lighting store nearby that I hadn't been to, as well. So I bought the candelabra fixture, a 15W bulb that would fit it, and headed over to the other store.

There they had lamp components in parts drawers, a very promising sign! I found several different types of base, but all in candelabra or medium size. One of the workers there helped me look, but we didn't turn up an intermediate base. We did turn up an adapter to go from a candelabra base to an intermediate base, though. I got that and a 25W bulb to fit, then went home with the lot.

Once home, I test fit the new fixture in the base with duct tape. I pulled out a selection of slides, and selected one with a nice thick feather sample on it to test the light level. I started with the 15W bulb and a thick section of the feather. The 15W bulb illuminated it, but not as well as I would like for students. Student's eyes aren't trained to pick out details yet. They need things well illuminated to help them see what they're supposed to see.

Putting It Together

I put in the adapter and the 25W bulb. That worked perfectly. Bright enough, without being too bright, even with a bacterial sample on a slide. In fact, the bulb aligned with the reflector in the base better with the intermediate base adapter. So I removed the old fixture from its bracket. Prepped the bracket and plastic welded the new base's fixture into place. I cut out the old fixture's wires, desoldered one end from the light switch, soldered and spliced the new fixture in. When it was all done, it looked like it was supposed to be that way. I tested everything to check for operation and safety afterward.

Then I added some labels to describe how to change the bulb to the outside of the case, and what bulb to use.

Now the "unrepairable" microscope not only works great, but can be maintained by an ordinary person without calling the "scientific instrument repair" service.

HFE: Sacramento Area Electronics Parts Source

There's a neat little place in Sacramento--next door to North Highlands--that sells lots of electronics supplies and surplus stuff, as well as some consignments. It's called HFE Electronics. It's at the prior location of HSC (Halted Specialties Corp., better known as HSC Electronic Supply.) HSC decided to consolidate, pulling out of the Sacramento location after over 25 years and focusing their attention on their Bay Area store and online sales.


HFE fills the gap that would have been left with the loss of HSC in this area. Not only that, but they've picked up for the Popkey Electronics store that recently closed here. They bought out Popkey's stock and are integrating it into their inventory now.

HFE is a fun place to poke around, ask questions of the staff (or, in my case, I more often get involved in helping the staff answer questions from other customers) and otherwise pick up all sorts of fun bits of electronics. They have everything from discrete components to ICs to equipment. There's new retail stuff as well as heaps of surplus and used stuff. There's lots of bits and bobs for those of us who like playing with microcontrollers, those of us who like building up analog circuits from scratch, amateur radio people, digital electronics types, tinkerers with pre-existing equipment, repairers of the $100 item with a broken ten cent part, and so on. Count me in all the above categories. I seldom get out the door without being about $100 lighter. :)

Among the things I noticed my last time in (no guarantees this will all be there when you walk in, especially if I beat you there) are:

• An Odyssey 2 game console from the 70s (based on the 8048 CPU, with lots of room inside the case for mods!


• Some Tek scopes and modules


• An old Mac SE/30 unit (sans keyboard and mouse.)


• Lots of interesting rocker switches


• A bunch of LCD displays with 44780 controllers and similar


• Oodles of LEDs and displays (I've picked up a bunch of dual digit 14 segment displays, among others.)


• Prototyping boards, tools, wire jumpers for solderless breadboards, and other proto stuff.


• Interconnects and sockets of all sorts of varieties.

This barely scratches the surface, and while some things are one-offs (like the Mac and Odyssey 2), much else is regular stock stuff. So if you're ticked about the fact that "Chicken Shack" doesn't have your favorite digital latch any more, take a stop by HFE Electronics.

HP-35s Calculator Review: an Engineer's Look

I've picked up an HP-35s calculator, see my full review.

The design hearkens back to HP's classic calculators for which it is still well known, such as the HP-41C, HP-65 and 67, and to a lesser degree, the HP-35. Unlike the original HP-35, the 35s is programmable and has lots of memory. It's more like an HP-67 or HP-41CV in many ways, which has spawned some unfair (to my mind) criticism.

I like the HP-35s a lot, you can find out why, and what I think could stand improvement here.

Fun with the "Sharpie Test"

Among my various hobbies is telescope-making. I'm in the process of making a Gregorian telescope right now. My daughters are also making telescopes. The older one is making her second mirror, an 8 inch f/7 for a Newtonian. The younger one is making her first mirror, a 6 inch f/8, also for a Newtonian telescope.

One of the parts of making a telescope mirror is what's called the "Sharpie Test", where you draw all over the mirror with a permanent marker (you can guess what brand usually gets used) to make sure you're working the entire surface of your mirror well as you grind it. They describe the test in detail on one of their tutorials over on gotgrit.com.

Well, I like to have some fun with my Sharpie tests, I get tired of just drawing plain old grid patterns. So I like to draw other things. Pizzas are a favorite. I also draw all sorts of cartoons on the mirror. They only last a few minutes, so it's very ephemeral as art goes.

My wife suggested I take some pictures, and after reminding me of the idea enough times I finally took pictures of a couple of my Sharpie test patterns, and now I've finally posted them. Here you go.

Enjoy.










Not all my drawing have cats, I just got more pressure into taking pictures when they had cats.

Busy, Busy, Busy

Preparing for the start of school has had me busy lately, as has a personal project.

I've just about finished a rebuild of my class site, the new version should be posted within the next two days (as I write this the new version exists only on my local disk.) I'm also preparing the early handouts and organizing my class notes.

Also, my daughters and I are making some telescope mirrors. We've just transitioned from polishing to figuring. So a lot of my spare time has been spent hanging over a Foucault tester looking at shadows.

So the blog is neither dead nor forgotten, just off to one side for a bit. Stay tuned!

Programming: Art, Not Science

In the course of a discussion over at the wonderful Hacker News site, I saw a hoary old canard raise its head, again. It did not dominate the discussion in any way, one of the things I like so much about Hacker News is that the discussions there tend to be very well balanced. The Ask YC and Ask HN threads are among my favorite reading on the internet.

The discussion was started by a question asking "Are You Religious?" The statement within this discussion to which I refer was part of a logic chain presented that ran something like this:

"Programming is a scientific discipline, therefore its practitioners think more scientifically than the common populace, therefore they have a greater likelihood of having a correct and enlightened outlook on X."

The X in question needn't concern us, particularly since it's so easy to kick apart the foundation of this line of argument.

Programming isn't science. It's not even scientific.

Programming is an art.

Programming is an applied art. Comparable to mechanical engineering. Both have connections with science, but neither is science. I've done both professionally, and of these two mechanical engineering has the closer ties to science, and requires far more rigor in the application of scientific processes. Programming, on the other hand, is much more at the "soft" end of the applied arts. Its connection to science is far looser, and much more akin to the connection between science and the fine arts, like painting.

One likely source of confusion is the college catalog term "Computer Science." Another is the common confusion of technology with science.

Computer science classes don't teach science, and the scientific method is absent in these classes. It's not there simply because it isn't used. Computer "science" classes are all about technique, as much as a class in ceramics or oil painting is about techniques in those arts, or a class in processes of materials is about techniques for producing desired items from raw materials. Technique is about the application of the products of science, but also a means of codifying and transferring practical experience.

I took computer science classes long enough ago that actually programming was not even a required part of the class. The focus of the classes was on determining the computability of problems, approaches for breaking problems down into computable pieces, and designing methods for incorporating computation into an overall problem solving process. We had plenty of material without spending any class time on computer languages. Yet this still was not science. The class was closely analogous to an introductory engineering class. It was about problem solving technique, not about science.

I have worked alongside actual scientists and done science in the course of my work. My electronic and mechanical engineering work, not my programming work. Programming is among the skills I have used to support this work, but that doesn't make it science any more than the writing, drawing and, yes, cartooning that I have used in support of such work. I have conducted scientific research in the course of my work--though I still don't hold myself out to be a scientist, the scientific work I have done was conducted with far narrower goals than the advancement of science. I only had to do enough research to answer some specific question or to bring a specific set of observations in line with existing theory. Once that was achieved, my research (and the support for it) came to an end. I haven't had to conduct research with the rigor necessary for peer-reviewed publication or the scrutiny contingent on a change in basic theory. Though I have worked alongside those who have, and contributed my work to theirs.

There are sciences associated with programming, to be sure. Information theory, mathematics, and so on provide programmers with theory to guide their practice just as materials science and physics provide theory to guide mechanical engineering. But that doesn't make engineers or programmers scientists.

The fact that programming is art, not science, does not take away from it in any way. There is a panache about science in our society that may make it seem to be so, but honestly society in general hasn't demonstrated much judgement in what is and isn't science. Technology is regularly mistaken for science. Technology is...technique, study of. Therefore art. Programming is a technical pursuit, a "practical art." Our society has been greatly enriched by its practical arts, there is no call to be ashamed of them if they are not science.

However, we should not look to the practitioners of these arts as being "more scientific" in their thoughts and outlooks than people of other disciplines. In fact, it is perfectly possible to be a scientist and still be as much a mere mortal in terms of personal philosophy as a non-scientist. Practitioners of practical arts are just as capable of being impractical outside their particular line of work as a masseuse, a hair colorist, or an astrologer. You can design a building that will stand while going home at night to work on proofs that the Earth is flat. You can write an efficient transaction processing system while in the middle of a years-long project seeking to write code to summon the spirits of dead people. You can give a good backrub then go home to practice telepathy on your pets.

Programmers are people. They regularly apply a range of problem solving techniques to their work. This does not impair their human capacity to adopt a wide range of philosophies and beliefs.

Programming is not a science. It does not require, or often use, scientific discipline and rigor. Its practice does not impart greater wisdom or intellectual incisiveness to its practitioners than any of many, many demanding disciplines.

Programming is an art. It is an art with magnificent application, and a medium that is accessible in a way that no other can approach, except perhaps pencil and paper. The works of that art are certainly reproducable in a way that works outside the digital medium are not. Confusing it with a science is not doing a favor to programming, and saying that programmers are elevated above some theoretical level of "the masses" in discernment isn't doing programmers any favor, either.

Programmers have every reason to be prooud, but for what they are, not what they aren't.