Hello, I just joined this forum today when I discovered that the community can provide help with school assignments. This is my very first post, so pleas go easy on me.
The instructions were essentially to build a relatively simple circuit and then present it in front of the classroom and turn in a detailed report. I am 20 years old attending a local community college in Illinois, with hopes of transferring to the University of Illinois at Urbana-Champaign or UIC. The class is called "Intro to Digital Systems". I had NO prior experience with electronics/electrical systems before this class aside from basic physics in high school. I think it would have been ideal to take a more basic class electronics class, such as Electronics 101 before jumping into ENG250, but unfotunately I was never recommended to do so (and ELT101 is NOT a requirement).
Unfortunately, I have been unsuccessful in building a functional circuit and would appreciate a little help with troubleshooting if possible. I will have to admit that I did not create/design the circuit myself and instead found it in a page that presents simple electrical/electronic projects for electrical engineering students.
I have attached the circuit diagram in this thread for reference.
I will also provide a link to the page where I found this project; it also includes a brief description of the circuit as well as the circuit diagram in case the attached file doesn't open for any reason: http://www.electronicshub.org/bike-turning-signal-circuit/
Here is also a link to a YouTube video that is embedded in the above page demonstrating how the circuit should work/look:
I am using a breadboard. I have built this circuit twice. The first time, the LEDs in the circuit lit, but did not pulse as they're supposed to. Also, I realized after a few hours of trying to solve the problem that 1) for some strange reason, the LED were brighter when I touched the top of metal transistors with my fingers. 2) I had not connected the ends of the 10k ohm resistors along the same path as indicated in the circuit diagram.
Because the above circuit did not work properly and I asked a laboratory manager for assistance to no avail (and an engineering instructor denied helping me at all twice and provided very little help a third time), I decided to re build the entire circuit once more. So I did just that. I re built the entire circuit, this time making sure that the 10k ohm resistors were placed properly. As I was building it, I was honestly expecting a fully and properly functioning circuit, thinking that I "fixed" a few previously made mistakes. Regrettably, this did not turn out to be the case.
This time, no LEDs lit up at all. Again, after hours of troubleshooting the circuit myself and then with assistance from a lab manager, no solution was found. In this instance, an electronics professor provided little assistance by saying: "check your ground". One strange phenomenon that I noticed was that when I touched the red/positive lead of a Digital Multimeter (DMM) to one of the legs of the LEDs (can't remember if it was the anode or cathode), that LED lit up! Also, if I touched the same lead to the following LED, both LEDs lit up. I could not get more than two LEDs to light up simultaneously. One more strange thing is that when I touched the same positive lead of the multimeter to one of the legs on the 330 ohm resistors, the voltage indicator on my power supply went from 12V down to nearly 0V.
These are the steps that I've taken myself and that others have helped me take to try to find a solution to my non-functioning circuit(s).
I would greatly appreciate any assistance based on the above information and I will be posting various photos that I will take of my circuits tomorrow, when I have access to it.
My final deadline is TOMORROW as I have already presented my project to that class and my professor gave me opportunity until 12/16/2014 at 2:00 pm Central time to present a functioning circuit. Otherwise, I will receive an "incomplete" and my grade will be lowered significantly. Please help as soon as it is possible to you and I will update you as soon as possible tomorrow morning. I know, it was a bad idea to post this the night before the deadline, but I was resigned to receive an "incomplete" as I found it impossible to solve the problem myself and received little to no help from others (including my professor). There are also no tutors at my school that can help with electronics/circuits, so this is my last chance.
ANY feedback is greatly appreciated and I apologize for the long post. Please let me know if I forgot to include something in my post. Thanks!
The instructions were essentially to build a relatively simple circuit and then present it in front of the classroom and turn in a detailed report. I am 20 years old attending a local community college in Illinois, with hopes of transferring to the University of Illinois at Urbana-Champaign or UIC. The class is called "Intro to Digital Systems". I had NO prior experience with electronics/electrical systems before this class aside from basic physics in high school. I think it would have been ideal to take a more basic class electronics class, such as Electronics 101 before jumping into ENG250, but unfotunately I was never recommended to do so (and ELT101 is NOT a requirement).
Unfortunately, I have been unsuccessful in building a functional circuit and would appreciate a little help with troubleshooting if possible. I will have to admit that I did not create/design the circuit myself and instead found it in a page that presents simple electrical/electronic projects for electrical engineering students.
I have attached the circuit diagram in this thread for reference.
I will also provide a link to the page where I found this project; it also includes a brief description of the circuit as well as the circuit diagram in case the attached file doesn't open for any reason: http://www.electronicshub.org/bike-turning-signal-circuit/
Here is also a link to a YouTube video that is embedded in the above page demonstrating how the circuit should work/look:
I am using a breadboard. I have built this circuit twice. The first time, the LEDs in the circuit lit, but did not pulse as they're supposed to. Also, I realized after a few hours of trying to solve the problem that 1) for some strange reason, the LED were brighter when I touched the top of metal transistors with my fingers. 2) I had not connected the ends of the 10k ohm resistors along the same path as indicated in the circuit diagram.
Because the above circuit did not work properly and I asked a laboratory manager for assistance to no avail (and an engineering instructor denied helping me at all twice and provided very little help a third time), I decided to re build the entire circuit once more. So I did just that. I re built the entire circuit, this time making sure that the 10k ohm resistors were placed properly. As I was building it, I was honestly expecting a fully and properly functioning circuit, thinking that I "fixed" a few previously made mistakes. Regrettably, this did not turn out to be the case.
This time, no LEDs lit up at all. Again, after hours of troubleshooting the circuit myself and then with assistance from a lab manager, no solution was found. In this instance, an electronics professor provided little assistance by saying: "check your ground". One strange phenomenon that I noticed was that when I touched the red/positive lead of a Digital Multimeter (DMM) to one of the legs of the LEDs (can't remember if it was the anode or cathode), that LED lit up! Also, if I touched the same lead to the following LED, both LEDs lit up. I could not get more than two LEDs to light up simultaneously. One more strange thing is that when I touched the same positive lead of the multimeter to one of the legs on the 330 ohm resistors, the voltage indicator on my power supply went from 12V down to nearly 0V.
These are the steps that I've taken myself and that others have helped me take to try to find a solution to my non-functioning circuit(s).
I would greatly appreciate any assistance based on the above information and I will be posting various photos that I will take of my circuits tomorrow, when I have access to it.
My final deadline is TOMORROW as I have already presented my project to that class and my professor gave me opportunity until 12/16/2014 at 2:00 pm Central time to present a functioning circuit. Otherwise, I will receive an "incomplete" and my grade will be lowered significantly. Please help as soon as it is possible to you and I will update you as soon as possible tomorrow morning. I know, it was a bad idea to post this the night before the deadline, but I was resigned to receive an "incomplete" as I found it impossible to solve the problem myself and received little to no help from others (including my professor). There are also no tutors at my school that can help with electronics/circuits, so this is my last chance.
ANY feedback is greatly appreciated and I apologize for the long post. Please let me know if I forgot to include something in my post. Thanks!
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