Hi All,
I hope someone can help me with my circuit dilemma. I recently built a simple blinking light with two electrolytic capacitors and two bipolar junction transistors (along with two LEDs and a bunch of resistors). It was working fine, but I took it apart, and when I put it back together, the LEDs would just stay on rather than blink. I have made sure that the capacitors are in the right way, and I put in the correct values for the resistors. I also swapped the LEDs and capacitors for known working ones. Here is exactly what I am using:
2 x 10 Ω resistors
2 x 4.7K Ω resistors
2 x 100 µf capacitors
2 x 2N4393 BPJ transistors
2 x 1.5 v AA batteries
2 x LEDs
The schematic is attached.
I substituted the 9 v battery for two AA batteries, and because of that, swapped the 470 Ω resistors from the schematic with 10 Ω resistors. I also swapped the 47 µf capacitors with 100 µf capacitors because I only had one 47 µf capacitor.
I think it has something to do with the transistors. I am not sure whether I am using NPN or PNP transistors. I am using different transistors than I had when it was working, but I tried those and they gave the same result, so I am pretty sure it is not the fact that I have changed them.
I have a bunch of parts at home, so if I need to substitute something to troubleshoot, I will probably have the parts to do it. Thanks in advance for any help.