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What to put in a HIGH SCHOOL intro electronics course?

Started by Ecnerwal December 3, 2015
I'm contemplating offering a basic, assume nothing electronics course 
during the "winter-session" at our school. 17 meetings over 5 weeks 
totaling about 40 hours. 

I want to offer basic concepts and hands-on, use a soldering iron, make 
stuff. Without treating it as magic, I'm also facing the fact that 
there's no assuming that the students will have had any advanced 
mathematics, so I'm going to need to step away from messy math and stick 
to simple stuff and the occasional "you'll learn more later."

By the time I actually _learned_ any of this stuff, I'd had 4 semesters 
of college engineering math and 1 or 2 barf-back EE courses that taught 
me nothing of use. Then I took electronics for physics and the textbook 
was AoE and the focus was on understanding things, not just memorizing 
what gain formula went with what resistor configuration around an op-amp.

But I can't really see trying to force feed AoE (though I still like it) 
to high school students (nor make them buy it for a 5 week course that 
won't work far into it.) On the other hand, I'm certainly not looking to 
repeat my glorious barf-back (rote memorization) experience, which 
really was a waste of a class.

I can probably limit the class to 5 or 6 students, (it's one of many 
offerings in a small school) and meeting times are all long enough to 
get some hands on in every session.

I don't have much of anything nailed down yet, but will need to do so by 
January (and decide if I'm gong to take a stab at it by Saturday.)

-- 
Cats, coffee, chocolate...vices to live by
Please don't feed the trolls. Killfile and ignore them so they will go away.
On Wednesday, December 2, 2015 at 7:09:00 PM UTC-10, Ecnerwal wrote:
> I'm contemplating offering a basic, assume nothing electronics course=20 > during the "winter-session" at our school. 17 meetings over 5 weeks=20 > totaling about 40 hours.=20
Doesn't exactly sound like an electronics course. It sounds more like you w= ant to create a "maker" course, using electronics. Maker is basically the c= oncept of just making stuff, and not really need to know the theory behind = it. Just follow steps A-Z, and boom you have made something. Most schools d= o this to get kids interested in the subject. Just the soldering alone may take awhile, and may be boring if you start of= f with this since one can't build anything until he learns soldering. So I'= d start off using solderless breadboards. Design a few kits using this conc= ept. And then maybe bring soldering into the course later when they already= have a few built kits under their belt. I do hope that they do get the very basics out of this - especially logic g= ates, since this will be vitally important if they do pursue further. Logic= gates isn't really math. Actually, it may be fun to give them a few logic = gates projects. Start off small like playing with LEDs and 74 series ICs, a= nd then move on up to 7-segment LEDs and BCD stuff. Here's an awesome audio project to use as a soldering project: http://www.ebay.com/itm/1Pcs-New-9-15V-Voice-Control-Level-Indicating-Voice= -Indicator-Module-DIY-Kits-/291548836254 Some good things about this kit: The kit is cheap! The solder pads are big,= the board is one-sided, and the silkscreen documents everything. And, it i= s very easy to troubleshoot. Once they finish building this, they'll have s= omething really cool to take home.
Ecnerwal wrote:
> > > I'm contemplating offering a basic, assume nothing electronics course > during the "winter-session" at our school. 17 meetings over 5 weeks > totaling about 40 hours. > > I want to offer basic concepts and hands-on, use a soldering iron, make > stuff. Without treating it as magic, I'm also facing the fact that > there's no assuming that the students will have had any advanced > mathematics, so I'm going to need to step away from messy math and stick > to simple stuff and the occasional "you'll learn more later." > >
** After teaching them to solder - why not divide the class into two teams and get each to build a "crystal" radio. Have them wind the coil ( 120 turns on a 2.5 inch former ) and use a germanium diode and piezo earpiece. First to hear a radio program gets a reward. The theory of operation is not too frightening and most are intrigued by how few parts are essential to make a working AM receiver. Obtaining a couple of usable tuning gangs could be an issue, if no old radios can be found. Then they can move on to *semiconductors* by making a two NPN transistor "flip flop" drive a pair of LEDs. Heaps of basic stuff to learn about with that. They should all learn to read resistor colour codes, any teenage girls will likely think they look cute too. I started out with "body-end-dot" types but you can give that a miss. ... Phil
On 12/2/2015 11:08 PM, Ecnerwal wrote:
> I want to offer basic concepts and hands-on, use a soldering iron, make > stuff. Without treating it as magic, I'm also facing the fact that > there's no assuming that the students will have had any advanced > mathematics, so I'm going to need to step away from messy math and stick > to simple stuff and the occasional "you'll learn more later."
How about teach and build a basic linear power supply. What does the transformer do? What does the bridge rectifier do? Ripple What does the filter cap do? Filter size What does this series resistor do? Why did it get hot? Oh so if we use two-1/2 watt resistors instead of one! What does the zener diode do? What does the Pass transistor do? What is the load. What is the load current. There is a whole lot of learning in there. Transformer ratios, different filter caps, current flow through the bridge rectifier, AC to DC, Ohms law, setting current flow in the zener, the transistor voltages. You can dig as deep into each section as your time will allow. Mikek
On 12/03/2015 02:39 AM, Phil Allison wrote:
> Ecnerwal wrote: >> >> >> I'm contemplating offering a basic, assume nothing electronics >> course during the "winter-session" at our school. 17 meetings over >> 5 weeks totaling about 40 hours. >> >> I want to offer basic concepts and hands-on, use a soldering iron, >> make stuff. Without treating it as magic, I'm also facing the fact >> that there's no assuming that the students will have had any >> advanced mathematics, so I'm going to need to step away from messy >> math and stick to simple stuff and the occasional "you'll learn >> more later." >> >> > > ** After teaching them to solder - why not divide the class into two > teams and get each to build a "crystal" radio. Have them wind the > coil ( 120 turns on a 2.5 inch former ) and use a germanium diode and > piezo earpiece. First to hear a radio program gets a reward. > > The theory of operation is not too frightening and most are intrigued > by how few parts are essential to make a working AM receiver. > Obtaining a couple of usable tuning gangs could be an issue, if no > old radios can be found. > > Then they can move on to *semiconductors* by making a two NPN > transistor "flip flop" drive a pair of LEDs. Heaps of basic stuff to > learn about with that. > > They should all learn to read resistor colour codes, any teenage > girls will likely think they look cute too.
Just make sure to teach them the clean version of the mnemonic. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
On 12/03/2015 10:33 AM, amdx wrote:
> On 12/2/2015 11:08 PM, Ecnerwal wrote: >> I want to offer basic concepts and hands-on, use a soldering iron, make >> stuff. Without treating it as magic, I'm also facing the fact that >> there's no assuming that the students will have had any advanced >> mathematics, so I'm going to need to step away from messy math and stick >> to simple stuff and the occasional "you'll learn more later." > > How about teach and build a basic linear power supply. > > What does the transformer do? > What does the bridge rectifier do? > Ripple > What does the filter cap do? > Filter size > What does this series resistor do? > Why did it get hot? > Oh so if we use two-1/2 watt resistors instead of one! > What does the zener diode do? > What does the Pass transistor do? > What is the load. > What is the load current. > > There is a whole lot of learning in there. > Transformer ratios, different filter caps, > current flow through the bridge rectifier, > AC to DC, Ohms law, setting current flow in the zener, > the transistor voltages. > You can dig as deep into each section as your time will allow. > > Mikek > > > > >
Some of JL's open-gate MOSFET tricks are fun. I might start with static electricity (sticking balloons to the ceiling works well in Mass in the winter), then do a FET demo, which naturally takes you into the idea of current and voltage. FETs are a lot easier for people to understand. I'd probably steer clear of inductance except as a mention, but capacitance is easy to demonstrate with a small water tank and pressure gauge, or even a balloon and air pressure, except that the pressure vs volume curve is nonlinear for a balloon. BJTs are hard enough to explain that I'd stick with FETs for the most part. 2N7000s are cheap enough that it doesn't matter how many they blow up. The maker thing is great, *provided you lift the hood and show the workings*. People tend to think that using canned Python libraries to make a RasPi blink a LED makes you a techie. Doing it with a 555 makes you learn something, even if it's on one of those miserable white protoboards. (New ones are OK for awhile, till somebody sticks in a TO220 or a 1-W carbon resistor and bends the metal out of shape.) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
In article <85b32307-8998-48db-ad52-228c30412a17@googlegroups.com>,
 groink1@gmail.com wrote:

> On Wednesday, December 2, 2015 at 7:09:00 PM UTC-10, Ecnerwal wrote: > > I'm contemplating offering a basic, assume nothing electronics course > > during the "winter-session" at our school. 17 meetings over 5 weeks > > totaling about 40 hours. > > Doesn't exactly sound like an electronics course. It sounds more like you > want to create a "maker" course, using electronics. Maker is basically the > concept of just making stuff, and not really need to know the theory behind > it. Just follow steps A-Z, and boom you have made something. Most schools do > this to get kids interested in the subject.
Not really - too many "makers" are _very_ voodoo/magick about how things work, and I'm shooting a bit higher than that. But I'm not aiming for the Maxwells equations approach (MIT 6.002 is a lovely on-line course, but scares HS students in my experience - unless you just fast forward to the glowing pickle at 36:45 in the first lecture.) But I do want this to be a hands-on laboratory course. I did teach ~600 freshmen engineering college students to solder a few decades back, so I'm good with that part, though there will likely also be some protoboard. [I think I'll leave the nitrogen laser out of this course, though - the thyratron alone would blow my budget. ;^> ] -- Cats, coffee, chocolate...vices to live by Please don't feed the trolls. Killfile and ignore them so they will go away.
In article <56606B19.1040505@electrooptical.net>,
 Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote:

> Some of JL's open-gate MOSFET tricks are fun. I might start with static > electricity (sticking balloons to the ceiling works well in Mass in the > winter), then do a FET demo, which naturally takes you into the idea of > current and voltage. FETs are a lot easier for people to understand.
...and that's worth the price of admission. I suspect you are right, but it's not something I'd likely have come up with myself.
> I'd probably steer clear of inductance except as a mention, but > capacitance is easy to demonstrate with a small water tank and pressure > gauge, or even a balloon and air pressure, except that the pressure vs > volume curve is nonlinear for a balloon. > > BJTs are hard enough to explain that I'd stick with FETs for the most > part. 2N7000s are cheap enough that it doesn't matter how many they > blow up.
Killing parts is fully expected. Otherwise they will have missed something they should know about.
> The maker thing is great, *provided you lift the hood and show the > workings*.
Eggs-act-ly where I'm trying to get to.
> Doing it with a 555 makes you learn something, even if it's on one of > those miserable white protoboards. (New ones are OK for awhile, till > somebody sticks in a TO220 or a 1-W carbon resistor and bends the metal > out of shape.)
I know well the foibles of proto-boards - I had a different lab with 3 of them tied to each of 20 computers that I had to keep functional (also a couple of decades back.) -- Cats, coffee, chocolate...vices to live by Please don't feed the trolls. Killfile and ignore them so they will go away.
On Wed, 02 Dec 2015 23:39:48 -0800, Phil Allison wrote:

> Ecnerwal wrote: >> >> >> I'm contemplating offering a basic, assume nothing electronics course >> during the "winter-session" at our school. 17 meetings over 5 weeks >> totaling about 40 hours. >> >> I want to offer basic concepts and hands-on, use a soldering iron, make >> stuff. Without treating it as magic, I'm also facing the fact that >> there's no assuming that the students will have had any advanced >> mathematics, so I'm going to need to step away from messy math and >> stick to simple stuff and the occasional "you'll learn more later." >> >> >> > ** After teaching them to solder - why not divide the class into two > teams and get each to build a "crystal" radio. Have them wind the coil ( > 120 turns on a 2.5 inch former ) and use a germanium diode and piezo > earpiece. First to hear a radio program gets a reward. > > The theory of operation is not too frightening and most are intrigued by > how few parts are essential to make a working AM receiver. Obtaining a > couple of usable tuning gangs could be an issue, if no old radios can be > found. > > Then they can move on to *semiconductors* by making a two NPN transistor > "flip flop" drive a pair of LEDs. Heaps of basic stuff to learn about > with that. > > They should all learn to read resistor colour codes, any teenage girls > will likely think they look cute too. > > I started out with "body-end-dot" types but you can give that a miss.
You can make a very satisfying capacitor suitable for a crystal radio with a toilet paper tube, two pieces of tinfoil, and a sheet of waxed paper. I was rather astonished that it worked at all, but not only did it work, it was fairly easy to peak up a station. I can't remember if you drew the moving sheet of foil up off the tube or if you twisted it around -- the principle is that you use the waxed paper as a dielectric, and bring the tin foil plates more or less into alignment by twisting or pulling. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com
On Thu, 03 Dec 2015 00:08:54 -0500, Ecnerwal wrote:

> I'm contemplating offering a basic, assume nothing electronics course > during the "winter-session" at our school. 17 meetings over 5 weeks > totaling about 40 hours. > > I want to offer basic concepts and hands-on, use a soldering iron, make > stuff. Without treating it as magic, I'm also facing the fact that > there's no assuming that the students will have had any advanced > mathematics, so I'm going to need to step away from messy math and stick > to simple stuff and the occasional "you'll learn more later." > > By the time I actually _learned_ any of this stuff, I'd had 4 semesters > of college engineering math and 1 or 2 barf-back EE courses that taught > me nothing of use. Then I took electronics for physics and the textbook > was AoE and the focus was on understanding things, not just memorizing > what gain formula went with what resistor configuration around an > op-amp. > > But I can't really see trying to force feed AoE (though I still like it) > to high school students (nor make them buy it for a 5 week course that > won't work far into it.) On the other hand, I'm certainly not looking to > repeat my glorious barf-back (rote memorization) experience, which > really was a waste of a class. > > I can probably limit the class to 5 or 6 students, (it's one of many > offerings in a small school) and meeting times are all long enough to > get some hands on in every session. > > I don't have much of anything nailed down yet, but will need to do so by > January (and decide if I'm gong to take a stab at it by Saturday.)
I would start with light bulbs or LEDs and batteries. Use the force/ speed analogy for voltage and current (the battery pushes, the current flows, yadda yadda). LEDs and resistors would make a good experiment -- not only do you get to show them that diodes only work one way, but you get to show them that more resistance = less current, and you give them about the simplest currently available circuit that one can use to annoy a sibling. Just showing them that a light comes on when the circuit completes should be cool for the susceptible ones. Make sure to explain that a switch really isn't much more than a couple of pieces of metal that come together or not, with specially-chosen metal for long life and a mechanical arrangement that makes the metal bits do what you want. In forty hours of instruction if you can get them from nothing to soldering and understanding what makes a circuit work, then you've accomplished something. If you can get them there and have some of them interested in carrying on, you've accomplished a lot. Particularly if it's early high school and middle school you may not want to push the soldering too hard -- today's soccer moms are going to be more comfortable with twisted wire and rubber bands than with soldered-up circuits (alas). I'd still show the kids how to do it, though. I think Phil's crystal radio idea is good if you can work it in. The one that I built with my kid was no-solder, used screws from the hardware store as necessary for connections, and was built on a shoebox for a chassis with toilet paper rolls or sections of wrapping paper rolls hot- glued onto the shoebox for coil and cap formers. One of the educational opportunities it presented was the tradeoff between germanium diodes (more sensitive, die with every distant lightning strike) vs. silicon diodes vs. schottkey diodes (hard to find small-signal ones, but they work great) vs. CB and BE junctions of transistors. -- Tim Wescott Wescott Design Services http://www.wescottdesign.com