Christopher Scaglione: 
Physics 355 
November 12, 1998 

I built the Greymark Sound Controlled Robot. The robot scoots around on the floor and when it bumps into something or hears a loud sound, it will back up and turn and then go forward again in a different direction. The microphone circuit is what allows the robot to "hear". The microphone circuit converts sound energy received from the microphone into electrical energy. The sensitivity of the microphone can be controlled by adjusting the potentiometer. The timer circuit is the "brain" of this robot. The electrical signal received by the microphone is then used by the timer circuit to output either a logic "one" (high voltage) or a logic "zero" (low voltage) which is then interpreted by the motor control circuit. A logic "one" is interpreted by the motor control circuit as a "Run Forward" command. A logic "zero" is interpreted by the motor control circuit as a "Run in Reverse" command. 

This Sound Controlled Robot kit took approximately seven hours to build. Soldering the components onto the circuit board was a relatively simple task considering each component was printed on the circuit board. What was a challenge was the mechanical assembly of this kit. Most of the screws and nuts I had to work with were only 2 millimeters in diameter. The kit included a small wrench, but unfortunately, even the wrench was too big for the nuts. The mechanical assembly required a lot of patience. Another challenge I encountered was the fact that the gears did not always remain in contact with the motor; even though they were installed correctly. To reduce the amount of space between the motor and the gears, the angle bracket which was attached to the large axle bracket was bent a little so that the gears came into contact with the motor. 

I enjoyed putting this kit together since this was something I had never done before. Electronic components learned about in class, such as resistors, transistors, and capacitors were all involved in the electronic assembly of this kit.

I built two kits for this project: the cassette player and the motion detector. These two kits were fun to putting together, but the trouble shooting was a little tedious though. The tape player was having problems playing tapes, the motor turns the tape reels and I was able to hear static on the head phones, but that was all. I tested all the components, they all worked fine and the polarities were right. The problem was that some solder had spilled over into another connection and created a short circuit. Now sound can be heard through the head phones, but only one side of the head phones works, the left side. If the plug for the phones is pulled out a little only the right speaker works. The motion detector worked the first time I hooked up the battery to it. With a good battery it can sense movement about forty to fifty feet away. Overall this project was definitely worth doing. 
 

My project is the AmeriKit AK-200 Stereo Tape Player Kit. I learn how to trouble shoot because my project did not work at first. I found bad connections to the head and volume control. I solder the connections and the tape player final worked but the motor turned to fast. I found to resistor and solder them between the power source and motor to slow down the motor. The tape player now works correctly. From completing this kit I learn that I am able to put together and trouble shoot kits. In the future, I will have competence to buy another kit to put together. 

Tom Juliano 

My project was the AmeriKit AK-200, build your own stereo tape player. The tape player was an excelent mid range kit to build. It wasn't to hard to build, but it was not that easy either. I already knew how to solder so that wasn't any problem for me. The only real problem I had was that the circiut board was very small and hard to work with. We had it here at school and with that gun and about 2 hours I had the tape player kit all together. I had very little trouble, trouble shooting with the tape player. The first problem I had was that when I placed the cover on, some of the motor wires touch something and kept the motor running even though I didn't press any of the buttons. That was easy easy to fix all I had to do was move the wires over and place the case on more carefully. The second and only other problem I had was the motor speed of the player. It was alittle slow in playing , that was easy to fix too because someone in the class also had the tape player and told me that there was a nut that I can turn to speed up or slow down the motor, so now it works perfectly. 

The sound sensor robot kit was easy to build. In fact, the hardest part was working with the little washers and nuts. The electronics were all basic components which is nice if a piece is lost or breaks and needs to be replaced. Another good thing about the kit is that you can change the sensor from a sound sensor via a 
microphone/amplifier to a light sensor with a photocell or an IR device with a few modifications to the basic circuit. It was nice to be able to build a small kit and understand what the circuit was doing, and also be able to troubleshoot the robot if it is not working properly. 

Soldering the components onto the circuit board was a relatively simple task considering each component was printed on the circuit board. The challenging I encountered was the fact that the gears did not always remain in contact with the motor; even though they were installed correctly. To reduce the amount of space between the motor and the gears, the angle bracket which was attached to the large axle bracket was bent a little so that the gears came into contact with the motor. 

The robot scoots around on the floor and when it bumps into something or hears a loud sound, it will back up and turn and then go forward again in a different direction. The microphone circuit is what allows the robot to "hear". The microphone circuit converts sound energy received from the microphone into electrical energy. The sensitivity of the microphone can be controlled by adjusting the potentiometer. 

I really enjoyed putting this kit together since this was something I had never done before. Electronic components which I learned in class, such as resistors, transistors, and capacitors were all involved in the electronic assembly of this kit. 

Ray Bodine 
Nov. 1998 

Being able to build and assemble this cassette player was enjoyable, and my favorite part of this Electricity & Electronics class. For one thing, it was a good experience using resistors and capacitors and other circuitry in a practical application. Also, this project was the first time I ever used a soldering iron or attempted assembling something electronic like this, and that experience was valuable. It was especially helpful to have some class time devoted for troubleshooting; asking for pointers in technique, and being able to figure out the mistakes I had made. First no sound came through, and it turned out there were a few bad soldering connections. In one place I had even forgot to solder one of the connections. This troubleshooting eventually brought about a pretty good sound. I think this project is an important part of the class, especially for students like myself who have little background in this arena of hardware. 

In Physics 355, textbook examples and lab experiments are only part of the complete Electronics and Electricity education. Hands-on experience building a working model of an orange, three-wheeled robot from a kit teaches skills in following instructions, soldering, trouble-shooting, and applying the knowledge learned in class. This robot goes in a straight-ahead direction, but when sound is sensed by a microphone, the wheels temporarily spin into reverse, causing the robot to turn. When the wheels resume spinning forward, the robot is heading in a new direction. 
 
 

Andre’ Barnes 

I worked on the digital multimeter. The project proved to be fun and also a great learning experience. Before starting this project I didn’t know how a soldering iron worked. After being showed how to use the iron, I went to work. The day I brought the meter to class, to trouble shoot and apply the finishing touches, I asked for the help of the brilliant Dr. Bidarian and no sooner did I ask him did he drop the PC board on the ground! While I was finishing it up I discovered a lead from a resistor was broke. I brought this issue up with Dr. Bidarian and he wanted nothing to do with it but that was OK because he helped me get it fixed. Now it was on to trouble shooting, this wasn’t a long task because being the dazzling student that I am, there weren’t many major problems. 

I was also able to learn a lot about gears, motors, turning coils, and RF frequencies. In addition to the corresponding components, I received an excellent knowledge base in troubleshooting technical aspects of electronic devices. The following diagrams are the schematics used.

The AK-870 Radio Controlled Car is a product of Omnitron electronics. The car run great with excellent features accompanied with it. The picture below is a schematic diagram of the transmitter and the receiver. There was quite a few troubleshooting done while building the car. The first problem was the two wires from the turning coil. They were so thin and one of the wires broke while trying to connect them to the circuit board. The wires from the coil aren’t bare but have a very thin vanishing insulating coating which was removed about half inch to the end. So I used sandpaper to take the coating off the wire before connecting it to the circuit board. The second problem was front wheels would not turn. I had to check the wires in the turning coil, check the front wheels by making sure they both turn in same direction and made sure that the turning magnet rotates properly on the front rod.