Monday, September 5, 2016

Snapping back into electronics


I started out with a much more difficult article then I had planned since I was asked by Joshua Miele with the Blind Arduino blog to do an article on how to setup Arduino IDE. This article is going to be much tamer. I think it is important for parents of Blind and Low vision children to be able to help their kids have a healthy love of STEM of all kinds. It is true that I am currently 46 and my brother and parents helped me only 2 years back but this holds true all the way back to day one of a visually impaired child's life. Just because we are blind does not mean we should not be exposed to everything possible. I recently had 2 foster children that were sighted. And I used my Snap Circuit kits to explain to them why they could not watch TV in the morning. I made a simple circuit with a fan, light, power supply, and a small connector that I could easily flick off with my finger. I showed them how when I flicked the one piece it disconnected and the fan and the light shut off. Then I showed them out on the street where the tree had fallen through the power line to our house.

The two foster boys were 3 and 5 and loved the demonstration. Not only did they love it but they couldn't stop making the fan blade fly off the motor like a Frisbee. Then something interesting happened. The five-year-old started making his own circuits. Nothing major but he quickly learned just by sticking things together what would work and what would not work. He of course wanted me to put the fan blade thrower back together once he destroyed it but that was the cool thing. Here I am the blind guy interacting with sighted kids teaching them very basic electronics and they are not even six years old yet. The same thing holds true for blind kids. I have yet to find a blind kid who does not like sticking his finger in the very safe snap circuits fan blade that when the positive lead is hooked up one way makes the fan blade fly off and when hooked in reverse it makes it stop, when the power is removed.

Parental and family help does not have to stop when you leave home. My Brother and parents proved this a couple years back. I suppose some could say I had been wining for some time since my wife bought me a robot kit in 2013 and with the help of my brother reading the instructions I built it. I will get to that in another blog right now I want to start with something more basic. After working with that robot I realized two things. I had forgotten a bit of my electronics in the last 20+ years and starting out with little bitty parts when you only partially remember what your doing is a bit difficult.

So I had been talking to my brother Tim who is what I consider a genius and if he reads this he will just have to deal with his big head. My parents were also on the phone they currently live with my brother. My dad as I said in my introduction was big in electronics and computers and my mom is no slouch in just about any subject I ask her about. To tell you the truth I wouldn't have graduated high school without her. Anyway I was talking to them about the trouble I had changing the circuit on the robot my wife bought me. Sure I could get Kathy, my wife, to help me put pieces in but that is not what I wanted I wanted a way to do electronics myself and to be able to quickly test something. I told my brother I would love to make parts that easily snapped together and acted like the real electronics parts. WE remembered the old kits from Radio shack and I thought it would be cool if we could make something for blind people that would be both accessible and fun to learn with. He told me that he had seen something like what we were talking about and after a bit of searching we found Elencro which turns out to be the people who used to make those old spring electronics kits sold from radio shack. Now they make Snap Circuits. I was pretty excited but I did not want to buy something I was not going to be able to use. I let it slide while I continued to play with my robot and do other things that were work related.

My brother and Parents however did not let it go. They purchased the Rover Deluxe and the Extreme 750 Snap Circuit kits and a braille labeler. While you would have to ask my parents how long it took them to use the labeler to braille the parts in the kit, I don't think it was over a few hours and they don't even know braille. The good thing is there is only about 80 parts in the 750 kit and not all of them have to be labeled. A lot of the parts can be distinguished by feel which makes this a great learning tool for the visually impaired.

You can watch these two videos I found on the two kits. They are not perfect but they have a good description of what comes with the kits.

Deluxe Rover: https://www.youtube.com/watch?v=NnINeI2cGc8.

Extreme 750: https://www.youtube.com/watch?v=xOOR6jupoCs

Once again my brother helped by building a few of the more difficult kits from the extreme kit so I could see what they looked like. Then he read the instructions while I built the AM radio. The radio

is just one of the 750 things you can build. I was able to quickly pick the pieces out because they labeled them with braille with the same numbers like S1 is a switch, R2 is a resistor. My dad put together the rover with some grumbling about how hard it was to read the picture instructions. While the instructions are good they are not as easy to follow as the Lego instructions but they are close. After doing a few kits with my brother. I told him to leave the AM radio together so that I could take it a part later and write my own instructions.

My idea was to take it a part backwards and write the instructions in reverse. If everything went right I would have as many instructions as I had parts (Not counting the circuit board). My first attempt worked great but was not very pretty. At the time It was a straight list of instructions and it was a bit hard to follow. I was working with Fred Otto a Project leader at APH on the new Snap Circuit project that we are working on. He suggested that rather than one list of instructions we break them up into layers because you stack parts on parts when building a circuit almost like how you build a Lego kit. With his suggestion and another idea of mine to sort the instructions to do the connectors first on each layer and then the specialized parts. This made it quicker to find the parts. So after all the mental work this is what the AM radio instructions I made looked like.

Project 306: AM radio

Parts List (29 pieces)

Count Part
1 Circuit Board 7 by 10 labeled A-G and 1-10
4 1 Connector
5 2 connector
2 3 connector
2 4 connector
1 6 connector
1 Antenna A1 (AM)
2 battery pack (2 AA cell 3V)
1 Capacitor c1(0.02uF )
1 Capacitor C2 (0.1uF )
1 capacitor c3 (10uF )
1 Resistor R4 (10k ohm
1 Resistor R5 (100k ohm)
1 Speaker (8 ohm)
1 Switch S1
1 transistor q2 (NPN Power AMP transistor)
1 u5 (High Frequency Integrated Circuit)
1 variable capacitor CV
1 Variable Resistor RV (50K ohm)

Note

To follow each instruction, the first part of the instruction before the comma is the part. The second after the comma is the placement. To place it count down the short part of the circuit board by letter and across by number. There are 10 columns and 7 rows. The First Row A and the last row is G. So if the instruction is as follows:

3 Connector, B2 B4

You start at the top left hand corner with the circuit board in a landscape layout. The top left corner is A1. Count down to the next row which is B1. Then move to the right to B2 which is the first placement. Then Snap the piece between B2 and B3 two to the right.

The layers in the instruction indicate that if you are on Layer 2 then your piece will be on top of another piece. If you are on Layer 3 your part will be on two other pieces and so on. The AM radio instructions only has three layers.

Layer 1

  1. 1 Connector, A3
  2. 3 connector, A4 C4
  3. 4 connector, A1 D1
  4. 4 connector, A6 A9
  5. 6 connector, F1 F6
  6. battery pack (2 AA cell 3V), B9 D9, Positive D9
  7. battery pack (2 AA cell 3V), F7 F9, Positive F9
  8. transistor q2 (6SCQ2 NPN Power AMP transistor) , B7 D7 C6
  9. u5 (AM amp Integrated Circuit), C3 E3 D4

Layer 2

  1. 1 Connector, A9
  2. 1 Connector, F1
  3. 1 Connector, F6
  4. 2 connector E3 F3
  5. 2 Connector, F6 F7
  6. 3 connector, D7 F7
  7. Antenna A1 (AM), C1 C3
  8. Capacitor C2, D4 F4, Positive on F4
  9. capacitor c3, C4 C6, Positive on C4
  10. Resistor R4, A4 A6
  11. Resistor R5, A1 A3
  12. Speaker, B7 B9
  13. Switch S1, D9 F9
  14. variable capacitor CV, D1 D3

Layer 3

  1. 2 Connector, C4 D4
  2. 2 Connector, A3 A4
  3. 2 Connector, A9 B9
  4. Capacitor c1, D1 F1
  5. Variable Resistor RV, A6 C6 D6

That is all you need to build an AM radio with Snap Circuits. I got tired of changing batteries with all the kits so I bought the AC Snap adapter at http://cs- and modified the above instructions by changing 2 instructions in Layer 1. So I added this to the end of my instructions in case someone wanted to change theirs as well.

Alternative Instructions

These instructions make it so you can plug the radio in with the AC snap found at sales.net/sncibaelac.html

to eliminate the use of batteries.

Alternative parts

Count Part
1 3 Connector
1 Ac Snap

Layer 1 Replacement Instructions

  1. AC snap , B9 D9, 6 Volt D9
  2. 3 Connector, F7 F9, Positive F9

As you see above you can build a pretty cool project with out to much information and it doesn't take a super high reading level for a person to follow the instructions. The Snap Circuit kits are made for people from 8 to 108 and it shouldn't be too hard for an 8-year-old Blind or Sighted person to follow these instructions. The great thing is you can change the circuits as you learn and improve them. I even have a simple change to this circuit that allows you to use an earphone rather than the rather quiet speaker. I am also working on an upgrade that would allow you to throw a switch and switch between AM and FM but that is turning out to be more difficult because I am not sure if I am going to be able to fit it all on one of the 7 by 10 circuit boards. We will see in a later blog what happens.

If you are thinking this looks a bit difficult for a young kid to do. Remember this is one of the harder projects in the Extreme kit you would not start with this one unless you already had electronic experience. The first project in the Extreme kit is the Light and switch project that only has eight pieces and thus only eight steps to build it. That takes no time at all and after built it is not hard to see how you can add fans, buttons and all kinds of stuff and that is how this electronic learning kit sucks you in for hours of play / work depending on how you look at it.

Some may think that this is only a toy / learning tool. That may be true for some but I use it for prototyping. As I previously said it was hard for me to get started with bread boards do to the small parts. Now though I could start prototyping ideas that I would later build on a bread board but first with big pieces. So for example I built a light sensor first with Snap Circuits which I found the instructions for on a Do It Yourself (DIY) page. Then after I understood how the light sensor worked I fought for a few hours to put the little pieces in a bread board and create it with real electronics. I didn't make the simplest light sensor. I used a 555 timer which meant I had to buy a special piece for snap circuits that took an eight leg Microchip. The cool thing was I could just take the 555 timer chip out of my snap circuit board and plug it into the bread board and other parts and it was now a real bread board prototype.

The reason it was important for me to do it first with Snap Circuits was it was easier to put together. Easier to follow where the connectors went, and I could find out if I really understood what I was reading on the DIY page. If I would have done it first on the bread board (I tried) and my circuit did not work (It did not),. I would not have known if I had miss wired it or if I had done something wrong (I did not). It was much easier for me to start with the Snap Circuits. So I start with the Snap circuits on many things I try.

One of the projects in the Extreme kit is even a continuity checker. I think there is even a simple analog multi meter. I have not built that one yet because it really is not accessible. I am actually making a digital talking volt meter one with the Snap Circuit kit and two special pieces. One being the PIC programmable chip that comes with the SC400 kit and another part I bought from Parallax that allows speech output. Note the speech module is not a Snap Circuit piece but there are ways to connect it and I will explain that in a later blog.

Finally, there is a robot that amazingly does not come with a programmable PIC chip but I have added one to mine. That way I can build something that a person can program and learn both electronics and robotics together. The original Deluxe robot comes as a remote control robot which was kind of fun driving around but I think it is more fun to build something that can be programmed. I wish the PIC chip had more memory but it is a very basic chip. Maybe I will add a small maker board (Arduino) into the Snap Circuits to give it more brains a bit later. This is also going to help me when working with my ActivityBot robot Kathy bought me because once I figure out a good circuit on my Snap Circuit robot I can transfer that over to it.

I hope this post has wet your appetite for what is to come later in this blog. I am going to continue to put up different instructions for all kinds of things. This will be my own accessible DIY blog because I find that there are a lot of things we can build with small modifications to instructions already found on the web. Snap Circuits are of course a great way to prototype things but I will also put up Arduino projects and even bread board projects that have nothing to do with either of the former. I will show how making something with Snap Circuits can be remade with Arduino and a bread board. I will even review a few things like a multi meter we found at work that is accessible for the blind and cheap.

By the way if you have comments on what would make instructions like the AM radio easier please let me know in the comment field. I had thought of putting them in tables with the part in one column and the instruction in the second but I thought a numbered list might be easier to follow. I am also interested in any Snap Circuit instructions for strange and unusual circuits. Also if you have electronic toys or tools you think are or can be made accessible let me know about them. I already have a lot of stuff but I am always on the lookout for things that make learning electronics for people with visual impairments easier and more fun.

2 comments:

  1. A digital multimeter provides many alternative functions however chiefly it is a meter, i.e. it measures electrical potential across one thing in volts. it is also Associate in Nursing ampmeter, measurement the quantity of electrical current through one thing in amps Garage tools.

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  2. This is really very good and detailed information for many who are willing to do this including me. I really enjoyed reading it and come to know about many other things. Thanks for sharing.

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