"The object of teaching a child is to enable him to get along without a teacher." — Elbert Hubbard
So you just finished your first Techsplorers class. What's next?
Remember, taking a Techsplorers class is just the beginning. You must try to invent your own creations in order for the magic to happen! And like pushing water downhill, we know this is something a young engineer wants to do anyway. Below you'll find some helpful advice and suggestions from our CEO and founder, Rodger Dalton. Even as an electrical engineer with over 20 years of industry experience, Mr. Dalton still remembers what it was like when he was in your shoes, hungry for knowledge and ready to jump in.
Don't wait for anyone to teach you — start teaching yourself. Get on the web, get your head in a book, and start learning on your own! Resist the temptation to constantly entertain yourself with video games, tv, etc. You must make the effort to think of a project you want to build. Don't just sit around waiting for mom and dad to sign you up for another class. Start making your own things outside of class!
This one is hard. Engineers have many interests and have a bad habit of jumping from project to project and never completing any of them. You can't do that — not in the real world and not in the world of an up-and-coming student who has so much cool stuff ahead of them to learn.
We're happy to give you free help via email, but there are also many other people out there willing to help a bright young student like you who wants to learn. So don't sit there in a corner; reach out to others and get help with your project ideas.
You're not going to build a spaceship or a laser that blows things up. Your project may not look the best and when you are first starting out you can't make super advanced things yet. But we promise you'll find out once you get going that even simple-looking things involve a lot of fascinating science. Simple things are not simple. A whole lot has to happen to make that light come on when you flip the switch. The engineers had to figure out how to make the technology work, but the users have no clue about all those cool details — they just flip the switch.
That's where the fun can be found in making those neat science and engineering discoveries, understanding them, and controlling them in order to make your "simple" project work. When you feel the rush of watching your little invention work after you've conquered and tamed the tricky science behind it, you'll know exactly what we're talking about.
This is never going to change. Develop the discipline to self-motivate now, not when the crunch hits you freshman year in college. You aren't going to achieve any of your dreams unless you can motivate yourself enough to put the video games down and start doing something more meaningful with your time.
Here are some items that you may want to consider buying if you are going to really get into building electronics projects at home. And of course, don't hesitate to contact us if there is something you're looking for or think that we should add!
We think RadioShack multimeters deliver the best performance for the money. We use the RadioShack 29-Range Digital Multimeter in class. Jameco also sells a low-cost meter with a temp sensor and lots of functionality.
Multimeters can get pricey though. The flagship top-of-the-line Fluke hand-held meter costs $500 and the multimeter I use as a professional electrical engineer working in industry starts at around $2,000.
Needless to say, mom and dad won't be buying you either of those last two.
Oh we envy you, young Techsplorer. When Mr. Dalton was your age he dreamed and dreamed about having an oscilloscope. These days you can get a very nice scope for only $350! Start begging mom and dad for your next birthday present.
The Rigol 1052E is a very capable oscilloscope with FFT function, excellent sampling BW, color display, etc. We have used them for a while now and we're really pleased. Eventually we plan to make a series of online learning videos that teaches how to use an oscilloscope, and we suspect there will be many adults who will want to purchase the course too.
Remember never use 60/40 tin/lead solder it is extremely toxic to children! If you see "60/40" anywhere on the label don't even touch the solder. Always wash your hands after working with electronics.
When buying solder always make sure it's lead-free, and we strongly suggest that you pay the extra money for the 3% silver solders as they are much easier to work with. Also, always make sure to use a temperature-controlled soldering iron when working with lead-free solder. Too high or too low of a tip temperature causes problems, especially with new lead-free solders.
The cheap soldering irons do not work very well in our experience and end up causing more headaches than they are worth. The copper tips corrode quickly and will not hold their shape; you must file the tips to keep them to a fine point and replace them when they wear out. Soon you've spent more than a good iron costs. We tried the cheap irons at the start of Techsplorers, and within a single class, the tips wore out and had to be filed! Plus, the kids struggled with them because of poor heating and bad solder joints. Be sure to check out our Soldering Kits to find the right soldering iron (and solder) for you.
In some classes we use solderable breadboards. The advantage is that they are configured exactly like the solder-less breadboards, so you can easily reference what you built on the solder-less board while soldering together a permanent version of the circuit.
Below we've collected a few possible project ideas. If you already have an idea of what you would like to make, send us an email and we will try to help you get it working. And if your project is really neat and you can successfully build one to prove that it does indeed work, we'll even add it here to the list of recommended projects!
Add an LED to the output of the slow oscillator that shifts the pitch up and down.
Play with the different resistor and capacitor values. First, predict what you think is going to happen, then make the modification and see if it does what you thought it would. You should be doing this to all circuits you learn about.
Redesign the circuit to use potentiometers instead of photoresistors.
Build Miranda's "R2D2" variant by using additional slow oscillators with their outputs also feeding into the CV pin of the fast oscillator. This makes a really cool sounding circuit!
If you are really hot stuff, here's a challenge for you: synchronize/lock together the slow oscillators so that the tones stairstep over and over. Can you design it to stairstep the tone up or stairstep the tone down? If you can develop that design on your own, you have very likely mastered the 555 timer.
Believe it or not, you can make a variation of the SolarBot that runs on batteries made from oranges or potatoes! Attempt this one and you will run into the very same design challenges that electric car developers face.
This one is similar to the orange challenge above but a bit easier. Can you tweak the design of your SolarBot to make it run inside your house off just the light that comes through the windows during the winter? Can you make it run in the shadow areas of the house in winter!? (Mr. Dalton left his SolarBot's solar cells connected one day thinking the light wasn't bright enough and came back into the room a few hours later to find that it had driven itself right off the table.)
You didn't need our help to see this one, did you? You can actually combine what you learned in the SolarBot and Wireless Alarm classes to create a remote-controlled car by using the outputs from the wireless decoder IC to control your motors! With two motors you can vary their speed to make the car turn left and right. That wireless IC has 8 different signals that can be sent over the wireless link. Some can tell it to turn left, right, forward, or backward if you learn what an "H bridge" circuit is (Google it!), and you can use the decoder outputs to control speed. All of that is possible with nothing more than the wireless ICs, some 555 timers, and transistors! And it's all within your ability to understand if you're motivated..
The Sonic Rangefinder circuit has tons of variables you can control by changing the component values. Do you know how to make the SR measure long distances? Do you know how to make the SR measure short distances with much higher precision? Can you calibrate the SR to make it accurate? There is an entire ocean of design possibilities that you can swim in.
Want a challenge? Use a light burst to eliminate the wires. Use a digital timer to increase the measurement precision even further.
This one is really easy and very cool. Take the microphone circuit used in AM Radios or Sonic Rangefinder, and combine it with the standard circuit for the LM386 speaker driver IC (shown in the datasheet). Run some wires from your bedroom down to the treehouse in the back yard or to your friend's house down the street. This blows the doors off the old soup cans with strings... you have tried that, right?
And if you're all that and a bag of chips, young engineer, figure out how to get rid of the wires and make an intercom system that puts your voice onto a beam of light! It is not as hard as you think. It probably won't go as far as the wires, but if you add some lenses (recall how to collimate a beam from the Wireless Alarm class) then you'll be surprised how far you can get it to go.
One of the 4-H Youth Development Professionals that Mr. Dalton worked with recently showed us this really neat robot arm. For such a capable device, $50 is an incredible price!
The ultimate challenge, of course, would be to take apart the manual control panel, tap into the push-button circuits, and control the robot arm using an Arduino microcontroller.
There are lots of advantages to using a microcontroller: (1) The reflective optical sensor head automatically calibrates itself to the track lighting conditions -- no more turning potentiometers to tune the sensor. (2) It's more intelligent in how it responds when it goes off the line (first making a gradual turn without slowing down so that it keeps its speed on the straight aways). (3) It accelerates to faster speeds on the straights or fully-tracked in the turns. This makes a huge improvement in the lap times compared to a standard LFR that does not use software control.
Of course, Mr. Dalton made all kinds of other secret tweaks in the software too. Let's see if you can beat his car when you take the class.
Dr. Kevin Guard recently told us about this great analog design platform created by Analog Devices. It is a bit advanced, but we think a motivated Techsplorer can jump in there feet-first take their learning to a whole new level.
This little device hooks up to your computer via USB, has nice GUI controls, gives you oscilloscope and logic analyzer "lab equipment" capabilities, and provides A/D converters, DACs, and discrete I/O if you want to use it to create a working design -- all for just $99! Wow!