Science!

Personal Memoirs of my adventures in science and how I got started in both science and electronics ...

Sparking My Interests .....

Tube Tester In the beginning there was nothing - as in vacuum (tubes, that is) ...

I grew-up in a time where the vacuum tube was king. Transistors existed, but were reasonably rare in commercial appliances. I recall watching TV on a large (20" tube) Admiral colour set (circa late 1960's) which used over 30 tubes! When it konked-out, my brother and I would remove every tube in the set, take a shoebox full down to the local Towers store, and Mom would go shopping while we tested tubes for an hour (you could tell it was the 1970's - a parent leaving two kids alone in a store for an hour !). Testing tubes was a tedious affair: look-up the number on a large rotating chart, configure the machine for that tube using a series of rotary switches and potentiometers, plug-in the tube, press the button, and HOPE the meter read 'BAD' (in which case, problem solved). If the tube showed good, back it went into the shoebox and on to test the next tube. Eventually, you'd find a bad tube, the clerk would retrieve the replacement tube from under the machine.
Our TV was a console model and was housed in a wooden cabinet. A single dial on the front selected channels 2 through 13 - UHF was simply not a thought in those days. Years later, we got UHF as well (there were two UHF channels to watch bringing the total to eight)! To get UHF we had an external converter box which sat on top of the TV ... turn on the box, wait a few minutes for the tube to warm-up, turn the TV to channel 3, and tune the UHF station on the dial on the box.

Crystal Radio, from the 'Boys Third Book Of Radio and Electronics' My actual interest in electronics has been there as long as I can remember. Since I was a kid (a little kid: like six) I had a fascination with electrical things - items ranging from extension cords to lamps. It started, I suppose, with Dad building simple flashlights consisting of a bulb and two 'D' cells taped to a yardstick. Other things I recall from my childhood include a Crystal Radio built from a design in the Boys Third Book of Radio and Electronics which we got from the local library. I found a drawing Dad made of the actual radio he built on the back of an envelope with a cancellation date of 1969 (Dad typically drew lots of pictures on the back of envelopes) - it consisted of a piece of wood on which an open-vane tuning capacitor from an old tube radio, a 1N34 glass germanium diode from Radio Shack, and a hand-wound coil on a piece of wood dowel was assembled (it was much more crude than the one shown in the pdf, but still effective despite the fact the tuning capacitor was shown on this diagram as being wired incorrectly). Dad had also built a telephone system where he attached two telephones to a board - I don't even recall if it worked (i.e. as an intercom) but it was a source of fascination nonetheless. My parents fostered my interests and I even had my own workshop from the age of six or seven. A few of the most interesting things my parents bought for my brother and I were a hand-cranked generator and a spark coil, both from Edmund Scientific and seen here in their 1977 spring catalog I recently found:

Hand Cranked Generator, scanned from Edmund's Spring 1977 catalog This hand cranked generator was a surplus unit used for army telephones. When cranked it would generate over 100 V: enough to light a 60W bulb! As well, one could not touch the terminals while cranking without getting a minor shock.

Spark Coil, scanned from Edmund's Spring 1977 catalog ... and I did say Sparking my interests ...

Now here was a toy I had a lot of fun with, a spark coil was similar to that from a Model-T car (albeit a newer version with a plastic case). Dad soldered three large brass bolts onto the unit. When a 6V lantern battery powered the coil it produced sparks between two copper wires 1cm apart. The coil would easily light fluorescent tubes. I can't count all of the experiments I did with that coil: everything from transmitting energy through the air by using two large tinfoil plates on the coil at one end (and a second set of plates some distance away with a neon lamp between them), sending high voltage through a trail of graphite filings between the two output terminals, lighting candles from the spark, to shocking my brother's friends who sat in a prewired 'electric chair':). The output, although high voltage, was safe enough because the current was quite low - still, the jolt from the coil was quite startling!

And so, my interest in electronics, and science, was fostered and grew. I had torn apart countless old televisions and radios (keeping many of the parts for future projects) and we had accumulated a large box of vacuum tubes. Dad would also buy electronics magazines like 'Elementary Electronics' from which I learned about various circuits. Of course, a good part of my interest was started by observing my brother, Michael, who was into electronics at the time. Michael had a "101 projects" electronics kit and had progressed from the standard projects in the kit (like an AM radio transmitter) to building several projects on his own including a light-flasher for roller skating which involved placing several bright lights on the bottom of roller skates attached to a transistorized multivib. circuit.

The late 70's were a time when electronics, as a hobby, was the "in" thing and learning kits were common. My brother had one of those "1001" project kits in which you wired circuits between components on spring clips - everything from code oscillators to AM radio transmitters. It was a "MyKit 7" as I recall, from the old Consumer's Distributing store, and it even had an Integrated Circuit. This was the funniest thing, though, since it was a THICK FILM circuit (not exactly what we'd consider an IC today). Components such as resistors and capacitors were fabricated using an applied-paste process onto the inch-square ceramic substrate. Even that was terribly unique since there were no real commercial products employing ICs yet (Computers, sure, but who had ever seen a computer close-up?) ... a few years later and chips flooded the market with everything from logic ICs to the ubiquitous 555 timer. You still see electronics kits like this available occasionally, although they are nowadays a 'specialty' item (whereas in the 70's they were available commonly).

Radio Shack Parts, 1976

For Christmas, well, most kids would look through the wish book .... I'd look through the Radio Shack Catalog :). The few odd parts to the left, taken from the 1976 catalog (from RadioShackCatalogs.Com) show the kind of stuff they offered back then (That site, BTW, is incredible and if you were into electronics during the 1970's it will surely bring back many memories). I'd frequently ask for either a "surprise kit" or a project kit like a P-Box Kit from Radio Shack. Each kit consisted of a red plastic box with a multitude of holes onto which the enclosed parts could be assembled to build a metronome, a radio, or, in this case, a night light (which I distinctly remember my Uncle Bob buying me one Christmas). I work with photonics now, but even back then found optoelectronics (including CdS photocells, LASCRs, and other devices like phototransistors) interesting and in this case, this kit taught me a lot about the operation of the photocell. The instructions for the night light, pictured here have a copyright date of 1968 "Allied Radio Shack" (this is the first page of the instruction manual which also has a good photo of what the completed project looks like). Some kits worked well (like the metronome and the night light) while others flopped (like the shortwave radio - never did have a knack for RF circuitry, even today) but I learned a heck of a lot by building these including some basic transistor theory (like "apply voltage to the base and the device turns on" - I had no concept of hfe back then) and learning to read schematics, relating symbols to the actual component. One of my other favorites was the One-tube radio kit which used a 1T4 tube and ran from a 22.5V battery (which fits into a C cell holder) and a AA cell for the filament. That one worked well as I remember and I have provided a PDF file showing the detail provided in these kits for the amateur electronics enthusiast. While I was totally solid-state centric (and dismissed people who, for example, said that tubes "sounded better than transistors"), I couldn't help but be fascinated by tubes especially since I had seen so many tube circuits in old electronics magazines from the 1960's. For those who loved these P-Box kits check out The P-Box Kits Page.

Aside from kits, Radio Shack also sold components, some individually (like the silicon phototransistor) and others as assortment packs like the transistors shown here. The transistors in the assortment pack were identified by a spot of coloured paint on each: four types were included. I had also bought a package of FETs, as shown here, and used them to build a touch switch ... in 1976, to the experimenter, FETs were quite novel.

While it's hard to find a good electronics surplus store these days (even in the seventies, electronics was already a 'dying' hobby), there were still a few stores like Olson Electronics in Buffalo, NY which supplied both surplus and new components. We'd buy a large (they sold it by the pound) surprise kit when we went "over the ditch" as we'd call it. Inside you'd find all kinds of junk including parts, motors, etc.! These provided a wealth of materials for projects.

Of course, many project ideas came from magazines like Elementary Electronics - the cover of the 15th anniversary issue (Nov-Dec 1978) pictured to the right. Really, we (my brother and I) entered into the hobby of electronics near the end of the era ... you just don't find many electronics hobbyists who build projects anymore (nor electronics magazines for that matter). Perhaps electronics just became too complicated with the advent of micro-miniaturization and the necessity of circuit boards for high-speed circuits, or perhaps kids in the next generation just found other stuff like video games to occupy their time.

My brother recently reminded me that the Rocket Computer featured in this issue was one of my projects, not his, as he had trouble getting the counter to work. Indeed, I recall taking to IC's readily although I also remember a lot of frustration over things like old CMOS chips which were excessively static sensitive and blew with dull regularity. I do remember using a surplus 7-segment display (from a Radio Shack assortment kit of LED displays - RS had a lot of "assortment" packs available with quantities of LEDs, displays, IC's, and other components) and adding a sound module to sound a siren before firing. Click on the cover image to see a more detailed view of the computer ... recognize the background? Very contemporary for 1978. Another project I had built was a touchswitch using a FET. FET transistors were fairly new then (at least to most experimenters) so it was novel. A hand-shaped piece of boxboard covered with aluminum foil served as the touch plate which, when touched, caused an LED to light.

My favourite electronics magazine at the time was Elementary Electronics. Popular Electronics was good, albeit the projects were too advanced for me at the time, and so EE had many simple projects that were easy to understand and learn how they worked (if not build them). Consider the Nov-Dec 1975 issue. Priced at $1.00, the main construction project of interest to me was a spaceflight computer (Project Spaceflight by Malcolm K. Smith). This analog computer project consisted of four utility boxes with a host of meters and switches (labelled, of course, with the requisite "DYMO" raised-plastic labels). The operator was required to "fly" the spacecraft by activating the rocket motor at appropriate intervals to keep it from crashing, all while watching the speed and height meters. This same simulation was popular in the late 70's on early home computers. The actual circuit was two integrators (using 741 OP Amps). Switching the rocket motor on produces acceleration upwards while "gravity" accelerates the spacecraft downwards. Integrating acceleration produces a speed signal (displayed on an analog meter). Integrating again results in height, displayed on a second meter). The goal being to land the spacecraft gently (i.e. at near zero velocity) at the height of zero (i.e. when landing).

I never did build that project, but reading through the article provided a description of how OP-Amps work (including how a split-supply worked) which would prove useful later when I started using these chips in various projects.

It was a timely article - the Apollo missions to the moon had just ended a few years earlier and the Space Shuttle was already announced - and so space flight was still an "in" thing. The author, BTW, was apparently quite a "Trekkie" since he makes many references to Star Trek episodes in the article (which even includes several photos from the series).

Another article I found useful in this issue was An old flash from a new IC which featured circuits using what was at the time my favourite IC, the LM3909 flasher. Other notable features in this issue were a plethora of advertisements for CB's (23 channel, of course, and one from Johnson for a CB featuring a very new LED meter display for signal strength), the required ad for Radio Shack P-Box kits (priced at $7.95 each and including both the one-tube radio and the night light), an Edmund Scientific ad, and a host of terribly cheesy classified ads in the back for everything from "Make $1000 a month stuffing envelopes" to "Beautiful girls wanting American men".

As well as Elementary Electronics (which provided a good start), I also regularly read Electronics Today International (commonly available in Canada) and later Popular Electronics.

Synthesizer Project Other projects I remember building? How about a remote telephone ringer which used a neon light as an opto-isolator and rang a loud bell when the phone rang. Or a timer (555 based) which connected to a pocket calculator - you'd key in "1+1" and the circuit pressed "=" once per second causing the calculator to increment and count in seconds (This was a project from Elementary Electronics magazine, Sept-Oct 1976, entitled "Mark-time counter"). Or a guitar booster which was cloned from a commercial unit (a small single-transistor amplifier, basically). Or a full-blown synthesizer which featured modules like a VCO, sine-wave shaper, and ADSR. This large project, pictured to the right, consisted of a wood frame which held a number of modules built into aluminum panels. It was the size of a commercial keyboard.

And in general, I built a bunch of little circuits on the breadboard using chips like the 4017 decimal counter, the LM3914 bargraph display, and the LM3909 flasher IC: things like handheld games using LEDs.

By the age of twelve I was constructing multi-channel colour organs using SCRs and audio transformers. Most of the basic designs were found in books like '101 electronic projects' which gave a schematic and a basic one-paragraph description ... the 'hobbyist' approach to learning electronics (which I still believe is the best way to learn!). One of my favorite plans was this Single Channel Colour Organ. I expanded that basic design, with the help of an article in a 1967 Electronics Experimenter's book (The "Musette" color organ by Don Lancaster originally in Popular Electronics July 1966), into a five-channel colour organ. Five audio transformers were used to drive five SCRs. R/C filter circuits on the secondaries were used to separate the frequencies for each channel - these proved to be the achilles heel of the design since they are sensitive to amplitude - and years later I would discover how active (OP-Amp) filters work which would have allowed vast improvement (And nowadays, when I built one again in 2010 for my daughter, I just threw a DSP chip at it).

GSR/Biofeedback Monitor, scanned from Edmund's Spring 1977 catalog At the time, my brother had entered the local science fair, building a light communication systemElementary Electronics Mar-Apr 1976 and, following in his footsteps as all little brothers strive to do, I built a project for grade 7 entitled 'A GSR monitor'. My (faulty) hypothesis attempted to prove that plants had nerves. The project (outlined lower on this page) wasn't spectacular but it was a start and involved some interesting electronics like a homebuilt strip-chart recorder. The basic unit itself was nothing more than a homebuilt power supply and a sensitive microammeter in series. Most parts came from a load of old electronics provided by a cousin in Buffalo, NY, who was disposing of a garage-full of old parts and books (electronics and ham radio). On a visit there, my parents picked-up a load of books and parts including things like indicator lamps - those nice little coloured jewels so popular in the 50's and 60's - and like any techie I incorporated lots of indicator lamps in my projects.
Oh yes, and where did I ever come up with the idea of a GSR monitor ?. Back to the old Edmund Scientific catalog ... in 1977 one the interesting things was to study biofeedback and such. Remember, this was the 70's, just after the drug-tainted 60's. Disco was IN, Psychedelic was IN, even mirror balls were IN (Yes, I found them in that catalog as well!). Could you tell this was the 70's from the caption 'Tune in to your tulips'?. And the colour organ I mentioned? They were big in the 70's as well. See for yourself in this advertisementColor Organ - Edmund Scientific in the Edmund Scientific catalog. People think of the 60's as 'psychedelic' but the 70's were almost as strange!

... More Serious Electronics ...

Radio Shack Engineers Notebook circa 1980 It is hard to imagine an engineer over 40 who does not have a copy of the Engineer's Notebook by Forrest M. Mims III pictured here (the 1980 edition). Radio Shack sold all of the components listed in the book (yes, they had chips and resistors in their retail stores) and so one could purchase an SN76477 complex sound generator for $2.99 (the 28-pin chip on the right) and wire it on a breadboard (also available at the store) to make all sorts of noises. Radio Shack's chips all came with a data sheet stapled to the back to assist the builder - in the case of this sound generator chip it was quite extensive and was the most complex chip many experimenters would have dared use - but even a pack of assorted SCRs came with a datasheet describing pinouts and application circuits. The other chip (on the left) is an LM3916 bargraph chip used to make 10-segment LED meters. I bet both of these chips ring a bell to many who cut their teeth into electronics during the late 70s and early 80s.

I took to digital readily - probably because I lacked the theory to understand analog properly! When you're self-taught in electronics by 'the hobbyist approach' you tend to focus on building things and not on how they work, yet to do analog justice you really need to understand circuit design, frequency response, have a decent ability to apply math, etc. Sure, I could design simple circuits and knew enough to put a large resistance in series to limit current but designing circuits like analog filters requires more complex math which I just didn't have. For digital there was little theory to understand - apply 5 volts and the rest is simply ones and zeroes! The math was exceedingly simple (once binary was understood) and it either "worked" or it didn't. Ahhh, a niche I fell into. Of course throughout the 70's computers were becoming more common. Most were the 'blinking light' style with large impressive front panels like the PDP-11's at the science center in Toronto that one could play 'tic-tac-toe' with. One local grocery store, Dominion as I recall, even went computerized with modern cash registers and a central computer (behind glass) complete, of course, with blinking lights. By grade 8 I had a my own computer, a REAL computer, an Ohio Scientific Superboard II. This glorious machine had 8K of RAM (expanded from the factory-standard 4K), stored programs on cassette tape, and displayed video on a TV as 24-column text. On the hardware side, I built I/O interfaces (to drive LEDs and read switches) and my own memory expansion using 2114 RAM chips. On the software side, I learned to program BASIC. I really 'cut my teeth' on that machine which was my first real hands-on intro to computers.

Science, like electronics perhaps, was in a similar boat for the home experimenter since I have a collection of odd magazines from the 1960's like Science ExperimenterScience Experimenter, 1968 with articles on the construction of Tesla coils, Van De Graaff generators, and more. I was too late to shop at places like 'Morris and Lee' (seen in ads in those old magazines), a science store in Buffalo which sold kits for many pieces of apparatus as well as things like diffusion pumps! It is possible I was born a few years too late. Then again, nowadays, the internet has filled-in the gap to a large extent allowing the rapid exchange of ideas just not possible before. Still, the notion that one could walk into a science shop and purchase a specialized thing like a diffusion pump?

Brain Candy: The Ontario Science Center ....

Ontario Science Center Laser Demo, Photo from a brochure circa early 70s I suppose I can't say enough good about my parents. They indulged my scientific curiosities, financed projects, and took my brother and I to the Ontario Science Center in Toronto at least once a year (A place I took my kids to when they were younger). The science center is an awesome facility featuring displays on a host of science topics ranging from astronomy to chemistry and up until recently featured a display on lasers. As a kid in the 70's I recall well watching the display with awe! The center opened in late 1969 and was groundbreaking in that the displays were interactive and visitors were encouraged to push buttons (see the "coffee" machine below). It was likely one of the first museums of its type.

Ontario Science Center Laser Demo, Photo from a brochure circa early 70s The focal point of the display was a huge carbon-dioxide laser. Built for Expo '67 in Montreal by the General Electric company of France, the laser found a home at the science center for the next thirty years until being retired recently. The laser was several metres long and had a rated power of about 100W. Demonstrators would evacuate the tube and then slowly leak helium (first), then nitrogen, and finally carbon-dioxide gas into the tube as fantastic colours appeared each time - you could see the gas travelling through the tube as the colour changed! After the last gas was added the laser began to lase and would burn a hole into whatever was in it's path. My fascination with that beast (and it was a beast by today's standards - we have a small air-cooled Synrad Firestar unit which has higher output powers) as well as the argon laser they had there (with its vibrant blue, green, and violet beams split by a prism) sparked my pursuit of studies in lasers which continues today (Hey, in a technology field you NEVER stop learning!).

Ontario Science Center, Circa 1970s If I had to say one one place 'turned my crank' for science it would be the Science Center. The place has changed in the past 40 years but it's still a fun place (and YES, I still consider science FUN). For a view of what the place had in the 1970's, just click on the map to the left to find a map of the facility with highlights of all the demonstrations. The old laser display was removed reportedly because they could not afford to repair it any longer. The Electrical display, featuring a large Tesla coil, as well as the Chemistry display featuring liquid nitrogen are still there (although they have moved). As well they have added some neat stuff like a small metal foundry. I would not have noticed when I was a kid, since I had no interest in astronomy, but the center also features a small planetarium and a few years ago an IMAX theater was added.

I haven't been there in a decade or so, so there are probably a hundred other changes since then!


Photo stolen from the OSC Memories page On the famed COFFEE machine ....

One machine that fascinated me (and one I likely monopolized at the OSC) simply said 'COFFEE' and was located in the center hall. The machine was built from discrete components and had a series of coils and capacitors for filters and oscillators. Lamps lit up the letters "C", "O", "FF" and "EE" as the machine spoke. Visitors could vary parameters using two analog pots to make the word sound different: bass/treble could be varied as well as the tone of the word from a "question" to an "exclamation". I recently located this photo on the OSC Memories Facebook page. The photo was stolen from this page - no photo credit was recorded on that site.

The machine was actually built by Philips for the Evoluon, a science museum in the Netherlands. I found a site dedicated to the Evoluon which features a nice article on the 'coffee' machine as well (the photo I have here was apparently taken from that site). Watch the movie of the Evoluon on that site and you'll see that the OSC, which opened in 1969, apparently took a number of ideas from the Evoluon (which opened in 1966).

Need more "Coffee"? You can hear a clip of that machine operating here (the sound clip was extracted from a video profiling the Evoluon center (when it was a science center in the 1960's and 70's) ... that video is available on the Evoluon site as well. The Evoluon, BTW, closed in 1989 as a science museum. The only point I debate on that site was that the coffee machine was given to the OSC in 1989 .... I recall it being at the OSC in the 1970's!

Personal note: in the 1980's I built a voice synthesizer based on a GI SPO-256 chip (Radio Shack actually sold these at one time). The first word it ever said: "coffee" :).

Other really neat stuff I remember at the OSC which is now gone:

  • The enormous tic-tac-toe game in the center of the main hall powered by a PDP-11 (probably an 11/45 with a full rack of switches and lights on the front panel). The center hall now houses a psychology exhibit but back in the seventies, computers were all the rage and still somewhat new to the public (I mean, they sent you bills, but you could never really interact with one). Other exhibits in that same area included a logic gate demonstrator for AND and OR gates which used ping-pong balls to show how logic signals 'flowed' through these elements.
  • In the mezzanine upstairs, the transportation display with a working model of canal locks in which a model ship ran up and down the locks. It even had a cool set of lights on a board just like real locks do (which control ship movement).
  • In the lower area, the atom exhibit with a display of Rutherford's Thorium decay experiment and the required small theatre showing the classic film 'The Powers of Ten' (you can find that film on YouTube nowadays: it is still worth watching).
Like I said, take a look at a map of the center showing highlights. If you were there in the 70's, it will probably bring back a host of good memories!

The kids at the Science Center

My kids in 2003 at the science center 'playing' with the Van De Graaff generator and having a hair-raising experience.

Adventures In Science ....

The science center had given me an interest in lasers which, more than anything else, fuelled my drive towards studies in physics and engineering. As a kid, and even now, I was never sure whether I should go into physics or engineering - as it ends up, I did both. Not sure I'll ever decide which is more interesting and certainly in the science center in the early 70's I found both fascinating. Lasers (physics) were really neat but so was the machine that said 'COFFEE' (engineering) and the big PDP-11 computer running the tic-tac-toe game in the center of the place. Hmmmm ... decisions, decisions ...

My interest in "pure" science developed in parallel to my interest in electronics. Like I mentioned above, I was always fascinated with optoelectronic devices making the bridge between the two subjects. Our family made annual trips to the CNE (Canadian National Exhibition) in Toronto and one stop was always at the Edmund Scientific (now Eftonscience) booth. I'd always pick-up science trinkets, lenses, and prisms. As a (young) kid, I'd put a prism into the path of a sunbeam coming through the front window and marvel at the intense colours in the spectrum. It was little inspirations like this that drew me into the field of science, as well as those frequent trips to the science center.

I had dabbled into building odd science projects: I had attempted (with no design and almost no concept of the theory required) to build a carbon-dioxide laser from a Pringles chip can ... oddly is did not work ;). Science looked like fun, but I didn't really have the background at all.

Now, one of this main vehicles that drove me into science was participation in science fairs starting in grade 7.

My older brother had entered a few science fairs in the past and, visiting him while he setup his project, I was intrigued to say the least. I recall being attracted to a project in which the students built their own electron microscope using a long glass tube, external magnets, and a television screen as the output (with the electron gun removed). At the time, I did not recognize it as a variation on the Amateur Scientist design but I was totally fascinated by it.

GSR Monitor Project, 1979 It was 1979, grade seven for me, and a science fair was looming at school. My interests, at the time, were primarily in electronics and reading through the Edmund Scientific catalog I was interested in building my own GSR (Galvanic Skin Response) meter - primarily as a lie detector. The electronics were simple enough: a basic transformer power supply (built in a wooden box) and an old (round-style) sensitive microamp meter (courtesy, along with a huge amount of other old electronics and magazines, of a cousin in Buffalo, NY). The basic unit worked but to really make it interesting I wanted a strip-chart recorder! Dad built the basic wood box and installed a slow motor and paper roll and I built the electronics which consisted of a single power transistor as well as a pen mechanism which consisted of an old relay removed from a pinball machine. When the resistance (GSR) of the subject fell below a preset value the pen moved. The entire project, along with the recorder and the backboard, can be seen here in one of the few photos I could find of the project (an old Polaroid instant photo).

While the project looked really neat (featuring glass jewel indicator lamps from the 50's), the actual science involved was thin at best - but back then for me it was all about 'BUILD IT'. Using plants as subjects (another idea from that old Edmund Scientific catalog I had mentioned at the beginning of this page) I found that talking to these plants made them respond. My conclusion: plants have nerves (! ouch !) ... Didn't even consider that the carbon-dioxide from a person's breath might have had something to do with the response. Suffice it to say that while the project looked impressive enough (lots of lights on the front panel and the moving pen was interesting to watch) it didn't do well at the fair. 'Build and show' is one thing at a science fair but if the real science is missing, so is the point. Regardless, I _learned_ by looking at other projects and so an important purpose was served! Failure isn't failure at all if one learns from one's mistakes.


Sound Telescope Project: photo from the Evening Tribune newspaper, May 5, 1980 Grade eight and I needed (OK, Wanted) another project. In the back of an electronics magazine I found an ad for plans (the company was 'Information Unlimited' as I recall) for a number of interesting devices including a small Tesla coil and a 'Sound Telescope'. Dad ordered both sets of plans and the sound telescope looked quite neat - picture a series of tubes, each resonant at different sound frequencies, with a sensitive amplifier and headphones. Mounted on a shoulder-mount (and looking a bit like a rocket launcher) we built it from a load of CPVC plastic tubes (the white, rigid type used for water, at a cost of $30 for all the tubes). A microphone from Olson electronics picked-up the sound which was fed to an amplifier scavenged from an old portable reel-to-reel tape recorder (bought at a garage sale for a few dollars) and was made even more sensitive by adding a homebuilt preamplifier between the the microphone and the amplifier (using one transistor - a design I used for a "linear power booster" for my guitar which served as a preamp). I built the amplifiers into a small plastic box from Radio Shack and powered it from two 9V batteries. The machine worked, and was amazingly directional. It won a few small awards at the fair including an honourable mention from the Youth Science Foundation and a bronze medal award from the US Army which was usually reserved for senior students (I was, apparently, the first junior ever to receive it). The science was certainly better (at least there was a tangible principle here) and winning an award, especially a bronze medal, certainly encouraged me to continue. (That bronze medal is still among my most cherished awards)

One of my biggest limitations might well have been access to information. Unlike today, where the internet has led to drastic changes in the way information is available, I was restricted to a large degree to magazines (electronics was a popular hobby back then so there were a number of periodicals available), the public library (where I had to manually search through old Scientific American articles from the stacks), catalogs (great for ideas), and old magazines like a 1968 copy of 'Science Experimenter' which featured a host of neat projects (a Tesla coils, a Van De Graaff generator), almost all geared to science fair projects. With electronics still a popular hobby, there were, at least, a number of decent electronics and surplus stores within a few hours drive. As a kid, one of our favourite shops was Olson electronics in Buffalo where we'd always pick-up a surprise pack of assorted electronic items for dirt cheap. Later, Active Surplus in Toronto became a favourite.


When I was in grade eight my parents bought me my first real laser. Indeed, I was fascinated by lasers since I'd seen them at the Science Center but to actually own one was almost unthinkable, and here was one available and almost affordable! The laser, purchased from Arkon Electronics (on Queen St. in Toronto and long since out of business) was a soft-sealed glass HeNe tube and a power supply kit consisting of a bag of parts and a photocopied schematic. The kit was simply listed in their advertisement in Electronics Today magazine as "HENE Laser Kit $149.95" (That seemed like an awfully large sum of money back then, but I sooooo wanted one - owning a laser was like owning one's own interstellar spacecraft :). I built the laser in a day, the power supply on a piece of perfboard, and Dad built a wooden box to house the tube. I used the laser for countless experiments in the two years it lasted before gassing-out (Old laser tubes, being soft-sealed, had particularly short lives). The night I got it working I was already experimenting with mirrors and making a laser light show - all to the tune 'Another One Bites the Dust' as I recall (funny the odd things you remember ;) - it was probably a first attempt to build a laser show like I'd seen at the CNE in Toronto. This new 'toy' was fascinating and it was amazing what happened when you put things like ornamental plastic in front: interference patterns galore!

First HeNe Laser
Seen here in the wooden box, the tube was mounted in three 'cradles' lined with foam. The output apeture was a modified RCA audio connector with the center terminal removed - mating fiber optics could be made cheaply with RCA plugs. A teacher provided me with a piece of fiber optics to experiment with.

Lasercom Project In grade nine I used this laser to build a light communications system for a science fair project in the local Niagara Regional Science and Engineering Fair. That project won me a trip to the Canada Wide Science Fair (CWSF) in Waterloo, Ontario (where I later studied). The project started as a laser-light show and ended-up as a full-fledged communications system. The trip to the CWSF was important to me personally as it showed me how to do research and allowed me to network with others. I got a taste of dorm life, had tours of labs at the University (which included seeing a massive argon laser), and had fun in general (they had PET computers at the dorms to play games, and a room full of the latest video games including 'Elevator Action' for which I built a MAME machine years later). At that fair I recall meeting one guy who built a number of homebuilt lasers, as well as another who built a really neat robotics project (it resembled R2D2 of Star Wars fame).

To give credit where due, my laser project was an improvement over one my big brother had built years earlier (also for a science fair). In his project (he got the original idea from an Elementary Electronics magazine in 1976Elementary Electronics Mar-Apr 1976) he used an LED (both visible and IR) as a source, and free-space as a medium (no fiber), picking-up the light signals using a parabolic reflector designed as a solar cigarette lighter. With an FPT-100 phototransistor at the focus of the reflector, gathered (modulated) light was collected and the signal amplified.

I present below the abstract for the project scanned from a typewritten (yes, word processors were rare in 1980) page I found in my parent's attic in 2002.

The First Lasercom System

The first Lasercom system was built for a demonstration in an "open house" night at my school. This is when I decided to use it as my science fair project. First, the laser had to be modulated. The idea for modulation was obtained from an old Popular Science magazine which described a foolproof burglar alarm system. It was hard to foil because it used 60 Hz modulated light source (He/Ne laser) instead of the usual plain red light beam, thus a flashlight cannot be used to "fool" the alarm system.

The article suggested the power line to the laser tube be cut and a small filament transformer be inserted in the circuit. A 60 Hz tone from the power lines is extracted by another transformer and the tone output was fed to the other modulation transformer. It was thought that if a 60 Hz tone can be impressed on the beam then a varying frequency signal could also be used. This method was tested and was found to work quite well.

In the first prototype system, the audio signal from a radio was fed to the modulation input on the laser. The beam was split in two parts by a piece of glass. The weaker beam was fed to a silicon phototransistor and to the input of an amplifier. The more powerful beam was reflected off a mirror and then off a second vibrating mirror which was connected to a speaker coil driven by the output of the amplifier. The mirror vibrated in step with the signal, thus the reflected beam also vibrated,making a small laser light show and also demonstrating the principles of light communications.

The diagram below shows how the original demonstration system worked:

First Lasercom System

Once again, two basic ideas came from books. The first was the modulated HeNe laser which I saw in an old Popular Science magazine. That approach, too, was similar to the one used in the Elementary ElectronicsElementary Electronics Mar-Apr 1976 magazine article in which impressed voltage from a series transformer was used to modulate the bias current (in the magazine article, modulating the LED bias current and in my case, modulating the actual laser tube current). The second was the light show which used a simple mirror bouncing on a membrane stretched across a speaker. Care to guess where that idea came from? Check this outEdmund Scientific Catalog 1977 to see the original 70's psychedelic light show. Most of these units used a projector with colour filters to produce multiple coloured beams. Mine used a HeNe laser to give a sharp 'dot' of light. My project was really just putting it all together: The modulated laser to send the audio signal, a photodetector and amplifier (modified cassette recorder) to receive it, and a speaker with a mirror to deflect the beam. There was some decent science in that project and unlike earlier 'build and show' projects, I was now putting-together concepts on my own. The modulation of the high-voltage, for example, was the taking of a basic idea and expanding on that idea ... the very nature of science itself (i.e. building on known concepts). This was required for any decent project.


Robot Arm Project By grade ten, I would have loved to have done a laser project but my HeNe laser was dead (it lasted only two years before the soft-sealed tube gassed-out) and besides, I was now fascinated by robotics having seen a neat robot at the CWSF in Waterloo the past year. I decided to use my old (not at the time it wasn't) Ohio Scientific computer to control a robotic arm (robotic arms were all the rage, after all, Canada just contributed the arm to the space shuttle). I learned all about interfacing (address and data buses, clocks, and all that jazz) and had my computer control a basic arm which was completely homebuilt. The robot is seen here to the far left with the controller (with a panel of LEDs indicating I/O status) towards the bottom of the photo. Another photo of the robot arm shows the arm mounted on a shelf above the controller and computer in the actual project display. The computer, a single-board with integral keyboard, was packaged in a homebuilt plywood case which held the computer, power supply, and the I/O circuitry built on 44-pin cards. The small TV atop the computer served as a monitor (which was large enough, given that the display resolution was only 24-characters by 24-characters.
That engineering project garnered a trip to the International Science and Engineering Fair (ISEF) in Houston, Texas. I did not place at the ISEF but again, the experience was incredible for I was able to see what is required to make an 'International' grade project - while it was a good engineering project it demonstrated nothing new or novel. I noted that the projects that _did_ win had certain characteristics and all used references from scientific journals like 'Applied Physics'. I had to get my hands on those and was told to check the local University library as they often have these collections available to the public. Brock, our local University library, stocks numerous physics journals which served as an invaluable source for ideas. The ISEF just overwhelmed me - the projects were awesome, the venue was huge (the Astrohall in Houston), students from around the world (Japan, China, Sweden, England, etc) were there ... it was a great place to exchange ideas. I was also turned-on to science, more-so than engineering at this point in my life.


OK, I was still intrigued by lasers (had been since I saw them in an old 1967 book on lasers) and desperately wanted to construct a working laser 'from scratch'. My fave? The argon. Having seen these at the Ontario Science Center as well as at a few laser light shows I was in awe at the vibrant green and blue beams. It is still my favourite laser, despite the fact that owning an argon is a bit more art than science. Soooooo .... I set out to build one. Gathering a load of information on the laser I decided a pulsed laser was the only practical way to do it (the gain is high, the average power dissipation is low). I learned basic glassblowing and using soda-lime tubing (which can be worked with a low-temperature propane torch) built a basic laser tube. It took me a week of experimenting with glass to learn _how_ to glassblow well enough to make that tube. The tube used electrodes from a spectrum tube (bought new from a science supply house and cannibalized almost immediately) and the ends of the glass tube were carefully sawed at Brewster's angle. Quartz pieces (compliments of the glassblower at Brock) were used for tube windows and epoxied on. For a vacuum system all I had available was an old Cenco single stage vacuum pump (compliments of the high school) and I purchased a lecture bottle of high-purity argon (along with the glass tubing, both from Sargent-Welch scientific).

Argon Laser Project - Invoice Again, my parents supported my science 'habit' and forked-over the $275.69 for parts as seen in this invoice from Sargent-Welch scientific for many of the materials required for the project. Several interesting items to note include (a) the fact that the glass was sold only in large bundles of 5 pounds, (b) the argon gas bottle and valve cost $67.20 in 1982, and (c) I ordered these parts in July for the science fair next March! Indeed, this project (and the ones which followed) involved major investments of time and effort - but I knew that was required for an "International" caliber project. In addition to the items on this invoice, several parts such as high-voltage diodes (Varo VG-20) and capacitors (high-voltage disc type) were ordered from an electronics component supplier adding to the cost of the project (which was probably $500). Of course there was also an order to Edmund Scientific for the aluminized mirrors.

Finally, the last item on this invoice "belt" was for a VanDerGraff generator I built for a friend which used a teletype motor to drive a belt within a piece of black ABS plumbing. Two stainless-steel salad bowls served as the top high-voltage terminal.

Well, constructing a gas laser, especially a low-gain one like an argon, on a piece of 2-by-4 lumber is begging for disaster and the laser never really ran as a laser. I could not afford proper (i.e. concave with a dielectric coating) mirrors and so a first-surface enhanced-aluminum telescope mirror was used with the hopes that the pulsed gain of the blue argon line would overcome losses in the laser. This was probably the biggest problem with the design: had I thought harder (and done some calculations using the gain threshold formula), I'd have made the laser 2m long since a 2m long pulsed argon would likely have exhibited over 30% gain and the bugger might have worked. Mind you, this was by no means a loss as I learned an ENORMOUS amount about vacuum systems, high voltage work, and other techniques I'd need now and in the future (even now, my early experiences with high vacuum are invaluable). Still, what to do with the argon in which I'd now invested precious time (started in July, completed by December) and (my parents') money? The answer was in an journal article (in the Journal of Applied Physics, Vol 48, No 3, pp. 1385) concerning the 'plasma pinch' effect in which a high current through a gas plasma generates a magnetic field which 'pinches' the plasma causing current to be reduced after which the plasma expands and current increases: the plasma current hence oscillates. By this time I was begging Mom to drive me to the local University library and leave me there for the afternoon. I spent hours in that place, bringing along with pockets of change for the copier.

Current Modulation Oscillograph I needed a decent oscilloscope (which I borrowed from Mr. Zavitz who serviced electronics and was also an Ohio Scientific computer enthusiast, hence how I met him) and an open-shutter 35mm camera to record the oscillations occurring in the discharge {This all seems so primitive today - now I simply plug a USB key directly into my scope and capture it}. Current was monitored with a Rogowski coil (a small transformer) in series with the discharge (small enough that its inductance did not affect the discharge much). A typical oscillograph is shown to the left. Because the photos were quite dim (the camera captured only a single trace of the scope beam) the output was traced onto a piece of translucent drafting film and placed on to of the original photo. The observed trace shown here was from the upper-edge of a low-pressure discharge of 88.2A. An 8.25MHz oscillation was observed.

Aside from the primitive vacuum system, the power supply consisted of a small neon sign transformer (obtained from a surplus store) with variac to control power, a few HV diodes ordered from an electronics supply house, and the handmade laser tube.

Current Modulation Project

The above photos show the power supply (with a small neon sign transformer), capacitors used in the project, and the laser tube, glowing, with an argon discharge. Click on the photo above to see a detailed view of the laser - all the gory details including copious quantities of vacuum wax used to seal the tube.

In grade 11 I entered that project, which also featured a presentation board of 'International' caliber (it was freestanding and about eight feet tall), and did extremely well at the local fair winning a trip to the International Science and Engineering Fair (ISEF) in Albuquerque, NM that year.

Current Modulation Project

I present the abstract for that project below:

CURRENT MODULATION IN THE PULSED ARGON-ION LASER DISCHARGE

This is an investigation of the phemonemon, factors affecting, and the causes of current modulation in the pulsed argon-ion laser discharge. If the amplitude of the modulation varies inversely as tube pressure and occurs only at high discharge currents, it may prove that the modulation is caused by the plasma pinch effect. The pinch effect, which may be responsible for the modulation during the main part of the current pulse, is calculated to occur at discharge currents of 30A or greater. The modulation occurred only when employing the 1 uF discharge capacitor and only at the upper and mid-trailing edges of the current pulse. The amplitude of the modulation was varied to a greater degree at the lower-trailing edge than at the upper-trailing edge. In addition, modulation frequency increased at the lower-trailing edge of the current pulse. The data suggests that the modulation does occur in the laser discharge, varies inversely as tube pressure and occurs only at high discharge currents. As large currents are needed to cause the modulation, these findings seem to indicate that a cycle of plasma pinch and destruction of the pinch is responsible for the modulation. Since the frequency of the modulation is lower at the upper-trailing edge of the current pulse, it seems that ion-acoustic waves are present as a cause of the modulation during the early part of the pulse.

First Award - Optical Society of America
Third Award - General Motors ISEF


It placed third overall in the ISEF (quite respectable) in the physics category. Aside from placing, the trip itself was just spectacular! I have fond memories of that trip - it was my favourite science fair trip of all time - and here are a few highlights ...

Hover, then click on any photo for a larger version

ISEF at Albuquerque NM 1983

ISEF at Albuquerque NM 1983

ISEF at Albuquerque NM 1983

ISEF at Albuquerque NM 1983

ISEF at Albuquerque NM 1983


Home to a huge hot air balloon festival each year, Albuquerque NM was and incredible experience.

Entertainment was top-notch and a Laserium laser light show playing Laser Floyd was presented on opening night.

Geek Haven: one tour I took was at the Los Alamos linear accelerator facility. You just don't get to see that every day!

We took a side trip to Santa Fe where the entire town is constructed in adobe style architecture.

Another tour I took was to Sandia Peak. At over 10000 feet, there was snow on the mountain.



At the fair in NM, I met James G. Small from MIT. At the time I recall saying something dumb like 'you wrote the article in the Amateur Scientist on the dye laser'? Close ... he wrote the article on the nitrogen laser, now famous with almost all laser enthusiasts! We talked for over an hour and essentially designed my _next_ year's project. I'd tried to build a nitrogen before, but did it all wrong using thick copper plates. He put me on the right path and for that I was grateful! In the bowels of Active Surplus in Toronto I found the required thin PC board (0.015" thick) from which the laser was built. I used that single-stage vacuum pump to evacuate the tube and rented a Q tank of nitrogen on my brother's account at the local welding gas supplier (he had an oxy-acetylene welder and so had an account with them for tanks). I borrowed his oxygen regulator which, with an adapter, regulated the flow of nitrogen into the laser. After a few blown PC boards, the laser was at last a success, and I was on my way to building a dye laser for experiments.

The banner for this page is a drawing from that Scientific American Amateur Scientist article written by Small in the 1970's describing the construction of a simple nitrogen gas laser which outputs in the ultraviolet. This article was, of course, the inspiration for the construction of my nitrogen pump laser.

Original Dye Laser This is a scan of the only remaining photo of my first working dye laser prototype (an old instant Polaroid photo). UV radiation from the nitrogen pump laser enters from the upper-right passing through the cylindrical lens (mounted on a focussing tube from an old microscope) and onto a cell containing Rhodamine-6G dye solution. The flat HR and OC are in the triangular mounts on either side of the cell. The entire laser was built on a piece of 1-by-6 wood. It was built simply to prove that it could indeed be done and despite the simple construction, worked extremely well producing a bright yellow beam.

The actual laser used in the experiment (outlined in a photo below) was much more stable: it was built on a 3/4" thick piece of aluminum with aluminum mounts for all optics, a precision rotating stage using multiple bearings for a diffraction grating used to select the output wavelength, and space was provided between the dye cell and the grating for additional collimating and wavelength-selecting optics. The main point of the experiment was to use an inexpensive dielectric filter as an intra-cavity etalon to reduce the linewidth of the laser output drastically.

1984 ISEF Project

The Laser and Controller from a circa 1984 photo taken for the local newspaper. Three gears on the side are part of the high-precision grating drive while the dye cell (outlined below) is under my little finger.

Click on the image for a much larger version



Apparatus

Dye Cell lasing. Radiation from the nitrogen laser enters from the left producing a line of excited dye molecules in the cell which is filled with a solution of Rhodamine-6G.

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Mark Csele's 1984 ISEF Project The apex of my science fair project experience is seen in the photo to the left. My 1984 science fair project placed first prize in the 35th International Science and Engineering Fair (ISEF) held in Columbus, Ohio that year. As well, I had won a trip from the US Air Force to visit several R&D facilities in Maryland, Ohio, Tennessee, Texas, and Florida - I was the only non-US citizen to have won such an award.

Mark Csele's 1984 ISEF Project The ISEF is the Olympics of science fairs and is the only international science competition for students in grades 9 through 12. In the 80's, the major corporate sponsor for the ISEF was General Motors. Nowadays it's Intel for the IISEF.

I left the project display board at the fair since it was a considerable expense to ship it back however I did remove the photos (and whatever else could be ripped from the board) and recently, a remaining piece of the project was located in my parents' attic as seen in these photos:

Observations

Observations: The right-panel from the project as seen above. Includes output spectrographs showing performance of the laser as well as condensed results.

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Apparatus

Apparatus photos from the center panel outlining equipment used in the project. The spectrograph used to record results in seen in the lower-right corner photo.

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Spectrographs

Typical spectrographs of the laser output taken with a homebuilt spectrograph built for this project. The top graph is the output from the laser using Rhodamine-6G, the middle graph is the output when using 7-diethylamino-4-methylcoumarin.


Spectral Width

Spectral Width - enlarged segments from the film spectrographs when the laser is operated on a single-wavelength. The width was decreased to almost 1 nm by including an intra-cavity dielectric filter which is tuned by changing it's incident angle.


This project examined novel tuning mechanisms for a dye laser. A crude (but high powered) nitrogen laser was used to pump a tunable dye laser. The project took a full year to construct. The abstract describing that project from the 35th ISEF:

WAVELENGTH SELECTION IN THE TUNABLE DYE LASER

The experiment presented will investigate the factors affecting the spectral characteristics of a nitrogen laser pumped tunable dye laser. The wavelength selection system is unique as it uses a medium resolution diffraction grating instead of a high dispersion type usually found in this type of laser, thus a grating used alone as a wavelength selector should yield high spectral widths of the laser output. The use of intra-cavity wavelength limiters -an optical slit or filter- should reduce the spectral width to approx. one nanometer. Rhodamine 6G; 7 diethyl amino, 4 methyl coumarin; sodium fluorescein; a mixture of the two preceeding dyes; and 4 methyl umbelliferone were employed as the organic lasing dyes. Ethanol was found to produce the strongest and most stable lases. Tested concentrations varied between 5 x 10-5 m/l and 1 x 10-2 m/l. Using a 600 line/mm diffraction grating alone, spectral widths of approx. 6 nm were produced. The use of an intra-cavity optical slit between the dye cell and grating reduced the spectral width by one-half, while the use of a dielectric filter (As a Fabry-Perot interferometer) reduced the spectral width to 1.2 nm. Using five dye solutions, a continuous wavelength range from 602 nm to 392 nm can be covered. Since the wavelength range is so broad, the laser may be useful as a spectrographic emission source; however, a high dispersion grating must be used to obtain low spectral widths. Data obtained on the use of a slit or filter can be applied to a laser employing such a grating.

First Award - American Association of Physics Teachers
First Award - General Motors ISEF
First Award - United States Air Force
Honorable Mention - Optical Society of America

There was real science in there: like my grade 9 project I took a common element (dielectric filters) and applied it in a novel manner. Where many lasers used an expensive etalon to reduce spectral width, this one used an inexpensive dielectric filter. And unlike my previous project where I lacked the mathematical knowledge to fully describe and predict the effect I was seeing, I researched this one thoroughly and understood the ins and outs of dielectric filters and gratings!

Here's a few shots from that fair:

Hover, then click on any photo for a larger version

ISEF 1984 Project - Columbus, Ohio

ISEF 1984 Project - Columbus, Ohio

ISEF 1984 Project - Columbus, Ohio

ISEF 1984 Project - Columbus, Ohio

ISEF 1984 Project - Columbus, Ohio


Where's My Project?? This sea of projects is the ISEF

My project in the 1100's

Proud as a peacock ... my first place award

One of the tours to the Columbus zoo. This little cat had a habit of jumping right at the tourists behind the glass.

Gary Hart, presidential hopeful, had a rally in Columbus while we were there.


USAF Award Plaque - ISEF 1984 Winning first award was a huge honour, but perhaps the best prize of all was the USAF award which included a week-long trip to air force R&D bases around the US (it was one of the most highly prized awards at the ISEF at the time and apparently, I was the first non-US citizen to ever win this award). It was a truly once-in-a-lifetime experience ...

Hover, then click on any photo for a larger version

USAF tour (ISEF award)

USAF tour (ISEF award)

USAF tour (ISEF award)

USAF tour (ISEF award)

USAF tour (ISEF award)


Our trip began at Andrews AFB in Washington. Air Force One was parked on the same runway as our plane.

We met many AF brass including the secretary of the Air Force

In AF style, transportation was on whatever aircraft were available: in this case, a C-130 transport!

The group of us at Arnold AFB in Tennessee. This was an official photo since cameras were not allowed at this base.

An official USAF photo of the group of winners taken at Cape Canaveral AFB in FL


To find out more about the laser I used in that project check out the Dye Lasers Page on the as the Homebuilt Lasers Site which also details the design of these lasers.

In the course of researching this project I had photocopied almost every laser article in the Amateur Scientist columns. As well, I used a good number of scientific journals for information: Applied Physics, Applied Physics Letters, and the like. I spent a good deal of time in the library at Brock University researching (this was, of course, long before the web and so information on amateur laser construction was much more difficult to come-by.


Mark Csele's 1985 ISEF Project Finally, in grade 13 (in Ontario, at the time, high school was five years), I entered a two-year project entitled "Wavelength Selection in Tunable Dye Lasers". The project was essentially a comparison of the spectral characteristics of the nitrogen-laser pumped dye laser (1984's project) to that of a new flashlamp-pumped laser. This laser was built around a capacitor obtained from a surplus defibrillator purchased from a surplus store in Buffalo, NY.

Mark Csele's 1985 ISEF Project A close-up of the project itself shows the flashlamp-pumped laser on top and the computer-control underneath. The computer, an Ohio Scientific 6502-based system, was built into a PDP-8/A case as seen here. The laser was configured as a spectroscopic light source - the computer controlled a step-motor which tuned the laser through the entire range. The laser was fired at intervals, and the transmission through the sample recorded. Beside the monitor and the keyboard are the controllers: the top panel controls the laser itself (charging of the capacitor and firing the flashlamp) and the lower panel the interface between the computer and grating drive.

The project was more engineering than science and the flashlamp-pumped laser lacked a totally unique element (unlike the nitrogen-laser pumped dye laser) - frankly, it was a matter of biting off too much. I should probably have concentrated on the optical elements of the laser instead of the computer-control system as I did. Regardless, I won the local fair and it was suggested that I go to the CWSF (in Cornwall that year) rather than the ISEF since the project was very similar to the previous year's entry. I placed second at the CWSF that year.

Off to School

University was a bit anti-climactic, at least the academic part: I was no longer 'the smartest guy in class' nor was I busy indulging in science which _I_ found interesting rather I was studying whatever was in the curriculum and in many cases, getting buried in school work.

My Dorm Room at University of Waterloo

School was comfortable enough. For several years during my first degree (at Waterloo, studying physics) I lived on-campus at the Village-1 dorms. My room featured a PC, a stereo, fridge, microwave oven (which as disguised as a filing cabinet since cooking appliances were forbidden), and (for one very hot summer term) an air conditioner carefully ducted through the window to exhaust hot air. In retrospect, the air conditioner contributed greatly to my success that hot summer since I was more than happy to stay in my cool room and study calculus, which is what I was there for in the first place. Of course, it was not an "allowed" item, especially since it blew breakers when other students in adjoining rooms tried to use a hair dryer - the addition of a simple timer to shut it down before everyone else awoke solved that problem (leaving me only to explain why each morning I had to dump a pail of extremely cold water into the sink).

... and despite school, I still had time to learn some neat stuff ...

During these days, I dabbled with a few interesting things like high voltage, made frequent trips to the surplus store in Waterloo, bought a ton of surplus at University surplus sales once a year, built a three-channel colour organ for nostalgia's sake (visible in the photo above), and made an interesting little transmitter to hijack FM stations replacing _their_ signal with my signal (which usually involved offensive music like einsturzende neubauten).

Old Spahgetti Factory Periodically, we'd make trips to Toronto, occasionally to visit the science center and occasionally to shop the surplus stores on Queen Street followed by dinner at the Old Spaghetti Factory .... always a treat! At the surplus stores we'd buy a whole bunch of computer parts, cheap, and use them for various microprocessor projects (like the EPROM programmer outlined below).

I have always enjoyed dabbling with high voltage (as you can see from the spark coil I had enjoyed using as a kid at the top of this page). Well, you meet some really strange interesting people in the dorm like one curious soul, Kenn Heinrich, who built a large Tesla coil in his dorm room. Kenn's coil consisted of two neon-sign transformers (15,000 volts each) driving a metre tall coil wound on black ABS pipe. In its peak of operation, it produced arcs 26 inches long! That corresponds to approximately a half a MEGAVOLT! (You don't measure voltages that high with a DMM after all). Numerous improvements (e.g. a low inductance spark gap) and numerous mishaps (e.g. starting carpet on fire when the side of one transformer exploded violently) led to the final version which caused a big enough stir at the dorms to have the Ontario Hydro safety inspector pay Kenn a visit! Needless to say that pretty much curtailed development before he hit the 'holy grail' of One Megavolt. Unfortunately, I can't find photos of Kenn`s coil in my memoirs but I did locate a photo of a second coil built by Mark Koehler, also at the dorms. This was a more 'refined' coil (meaning it did not start any fires, wipe out any cable systems, nor punch holes through aluminized dorm mirrors being used as capacitors) using a large double-sided printed-circuit board we obtained from K-W surplus as a capacitor (visible in the background).

Marx bank Generator Aside from helping in the development of those Tesla coils (I had learned a lot about fast discharge circuits from my days of building lasers for science fair projects which was useful here), I built myself a Marx-bank generator in my dorm as seen here (the original application envisioned was likely as an excitation source for a pulsed neon laser). The device produced about 200kV but with a risetime in the nanoseconds - the Fourier transform is quite broadband so it kills almost all forms of communications. The generator was built from pieces of ABS sewer pipe (one of my favourite materials) used as coaxial capacitors with spark gaps fabricated into plumbing tees between the caps. That generator threatened my new PC more than once (I had already had to rebuild the output drivers on my CGA card a few times due to a flaky monitor and wasn't looking forward to diagnosing yet more problems) so it was shelved before it cost too much time in repairs of adjoining equipment ... in a ten-foot square dorm room there isn't much space to escape a rogue high-voltage arc that follows some odd, unpredictable, path!

Radiation Warning, Kr-85 Well, I received an e-mail from Kenn. Might be respectable now (two kids and such ... who knows, might even have a minivan by now :) but he _has_ outlined his coil experiments on this page. Yes, ABS sewer pipe was one of my favorite materials to build lasers, etc. from and yes, the 'offending' laboratory equipment was hidden under my dorm bed when the safety people paid Kenn a visit :). He did fail to mention the radioactive krypton-85 filled tubes we once got at a surplus store in London, Ontario, though ... (The same one which was playing Kate Bush music after poor Kenn had just been subjected to an hour and a half of this by me on the trip down ... doesn't it just figure :)

Z8 Eprom Programmer I also learned about microprocessors and microcontrollers and built my own Z-8 based EPROM programmer to further my hobby in computers. Until then, I had built numerous interfaces and memory expansions to my old Ohio Scientific computer but had never actually built a microprocessor system "from scratch". In those days, EPROMs were a necessity and few people had a programmer: mine used a Z8-BASIC chip (Z8671) and was wire-wrapped on a piece of perfboard. A bank of DIP switches configured the socket for various types of EPROMs (the unit was originally designed for 2716 and 2732 types but was expanded many times to accomodate multiple types). These switches configured the function of various pins as well as voltages (Vcc and Vpp), the rest was done in software written in BASIC. To use the programmer the main program was first uploaded from a PC to the unit then data was uploaded/downloaded to the chip in the same manner. Visible in this photo is a stack of 2K RAM chips with the chip-enable lines bent upward and wired to a 74LS138 decoder (2K chips were all that was available cheaply from surplus suppliers at the time).

Here are a few close-up details of the Z8 Eprom programmer including the Bottom of the board showing the mass or wirewrapping and the Switches allowing the programmer to be configured for various types of chips (these actually configure the function of various pins which change based on the chip in use).

They say school "teaches you to learn" and that it did. The art of learning is one all student must master and included many late nights studying including, in my final year, the occasional "study party" in the physics building where a bunch of us got together to attempt to decipher what the prof covered. At these parties, attended by twelve or so students, we'd get together and try to solve problems from class. We'd collect $2 from everyone, run out to the closest convenience store to buy chips and Coke, and spend hours poring over complex problems. When someone got it right, we'd all examine _how_ to solve the problem properly. All part of the learning process!

After I did physics at Waterloo, I did computer engineering at McMaster, and then real-life set-in somewhere along the way (mortgage, marriage, kids, cat ... I hear a country song in there somewhere). Still being an 'Amateur Scientist' at heart, I have constructed several lasers since those science-fair days, many outlined on the Homebuilt Lasers Site. And since I'm still into embedded control I have built a number of Projects, most PIC-based. I have even recreated my old colour organ, this time using a DSP chip to accomplish all filtering.

A New Chapter .... Quite Literally

Photonics Program Grand Opening Enter the launch of the Photonics programs at Niagara College in 2001 and I find myself once again (happily) knee-deep in the field of lasers, teaching numerous laser courses at the technician, technology, and (when we offered it) applied-bachelor level (see the Courses page on the Technology website and check out PHTN1300, PHTN1400, PHTN1432, and PHTN1500). The article to the left, from the Evening Tribune (Oct 3, 2001) shows the grand opening of the program in which our college president Dan Patterson used my baby flashlamp-pumped YAG laser to cut a ribbon and open the lab. Our programs, and new laboratories therein, have required the construction and rebuilding of many lasers and laser systems. Our high-powered laser lab has three large-frame argon-ion lasers (Coherent Innova-90 and Innova-200, and a Spectra-Physics 2020) as well as a few smaller air-cooled argon and kryptons, several carbon-dioxide lasers including an MPB DC laser and several Synrad RF lasers, a Lumonics 600 excimer with Hyperdye-300 dye laser, a tunable Ti:Sapphire laser, two YAGs (one diode-pumped Lee LDP-20 and one flashlamp-pumped Quantel 660 unit), and a host of other laser projects. As well as lasers, my other forte is high-vacuum and thin-film technologies. We have built a Mass, Optical, and Infrared Specroscopy lab at the college which features two turbomolecular pumping systems for reprocessing gas lasers (HeNe, Ar, Kr, etc) and for mass spectroscopy work. We also have a full class-1000 cleanroon for production of thin-film devices. Our deposition facility include thermal, sputtering (Lesker PVD-75), and eBeam systems. Our programs are in full-swing and I shall be busy teaching courses in Photonics for many years! While originally hired at the college to teach computer engineering technology, my teaching load is now primarily photonics courses.

Fundamentals of Light and Lasers

I am the author of a book entitled 'Fundamentals of Light Sources and Lasers' published by John Wiley & Sons (ISBN 0-471-47660-9). The fact that 'Wiley' is the publisher is a non-intentional, however appropriate, match since 'Wile E.' is indeed my favourite cartoon character and indeed I've had a few 'Wile E.' moments in the lab (as in the production of smoke followed by the expression 'Oh Well, Back to the old drawing board').

Focussing primarily on lasers, the text introduces background concepts necessary to understand lasers including the nature of light itself, blackbody radiation and atomic emission, as well as basic quantum mechanics. Lasers are covered in detail with practical, real-world examples (as well as experimental proof of many otherwise esoteric concepts) found throughout. The last six chapters of the text outline various laser systems in detail including visible, UV, and IR gas lasers, semiconductor lasers, solid-state lasers, and tunable dye lasers.

As well, I have also written an article on lasers for the Kirk-Othmer Encyclopedia of Chemical Technology also by Wiley.

And so, I am back in the field in which I started although some things have changed: I have better equipment at my disposal (like thin-film evaporators for fabrication of precision optics and turbomolecular high-vacuum systems) and more lasers in my lab than I'd have ever dreamed possible. I think of my return to lasers as my having come 'full circle' although engineering has certainly helped, not hurt, my knowledge of lasers since I now tend think "like an engineer" about problems which are otherwise purely scientific in nature.

Weird Science:

I was asked to help with a video for the police services video unit to used for training officers in electrical safety issues - for example how to deal with situations involving fallen wires. Here's a few shots from the video.

The script required a chicken to be fried with electricity ... a difficult feat unless you've got a LOT of current available. The producers of the video contacted the utility and were told it couldn't be done so I was contacted next. In this case, the chicken was fried with three-phase 208 Volt AC in our laser lab. That lab has it's own transformer and safety shut-off switches allowing a 'safe' demonstration Don't try this at home, even if you have 200 Amp, three-phase, 208 volt service. It's dangerous, and besides, it smells REALLY BAD - so much so that the class in the room adjacent the lab was 'affected' (I feel like a guy on Mythbusters saying that :).

Finally, another segment required the similar treatment of a hot dog. Again, a high current was used causing the weiner to heat and split as seen here.

In the end, the video made a graphic demonstration of what electricity can do to flesh with the hope the viewer has newfound respect for it. That chicken was fried with 208 volts ... most power lines are between 1 and 15 thousand!

Weird Science, for a good cause!

Today ....

I still like science, and electronics, and never did decide whether I wanted to be an engineer or a physicist when I "grew up". For the first ten years of my career at the college I taught embedded systems design (and did a host of embedded projects while 'moonlighting' as well). Today, this topic has been relegated to hobby status and I continue to design and build a number of projects using both PIC and dsPIC microcontrollers. In 2010, I used a dsPIC chip to build my daughter a color organ for the rec room (The article was published in Circuit Cellar magazine in April 2011).

Laser BeatlesIn the field of science, I still find lasers fascinating ... good thing, too, since the majority of my entire teaching load consists of courses on laser technology. I still enjoy a good laser light show and while camping in the Rochester NY area in the summer of 2011 took the family to "The Beatles in Laser Light" show at the planetarium there.