# transistors

1. ### Transistor substitutes

Transistor FNCS 0014 and FANC 0070 substitutes
2. ### What is the simplest switch circuit I can build for a 30-amp (220v) machine?

I was considering using a Rele but they don't work very well with high current (the ones that work are expensive) since its a high current I need the circuit to hold and at the same time not have much resistance when the current is passing through it. Is there any circuit I could use? I think...
3. ### flashing LEDs circuit

Found this simple circuit on youtube and I'd like to know the equation for how to vary R and C to change the flashing frequency. Also, how to increase the current through the led with 3.3 V battery as power source to maximize brightness.
4. ### mesh current analysis in bjt circuits

How to use mesh current analysis instead of thevenin's theorem here to solve for all currents and voltages in the following bjt circuit? How should i make the closed loops in order to analyse?
5. ### Electron flow in common base and common collector transistor configurations

Could somebody explain the working of common base and common collector transistor configurations?How do the electrons begin flowing in these configurations?
6. ### How does middle layer of a transistor get a charge in order to get reverse biased or forward biased accordingly?

I dont know much about electronics.While studying about transistors,i had a doubt about the middle layer.If the emitter and middle layer becomes forward biased, and collector and middle layer becomes reverse biased,how does middle layer have both the charge in order to get reverse and forward...
7. ### H-bridge using IR2184 chip.

Hi all, I want to implement a H-bridge driver circuit. May I know how to make some changes to the circuit above so that it forms a full-H-bridge using transistors. I attached my LT Spice file below :) Thank you for reading.
8. ### Small pull-down resistor for mosfet (fast switching, high capacitance)

Hi readers, When I used this IRF 3205 which has high capacitance between the Gate-Source of the mosfet, whenever I add a lower pull-down resistor, the switching becomes faster and faster (visible nice square wave). For my case, for IRF 3205 to fast switching at 20kHz (nice square wave), it would...
9. ### Differential amplifier comparator troubleshooting

I have build a differential amplifier comparator and it works fine except that instead of switching voltage between zero and 5v, it toggles it between 3.5v and 5v. So, I would like to know if there's a way to make it switch between 0-5v. The schematic is as follows
10. ### Amplify Flip Flop signal from NE 555 timer using transistors

Above is the graph across R7 (Load). Hi readers, Flip Flop with Ne555 timer means turning on an led and another one off, as shown in picture, and this alternate on and off pattern continues. This video can be found at Click Here . I have succeeded in amplifying one of the 2 signal as shown in...
11. ### BJT Common Emitter Large and Small Signal Research

Hi, I want to study about BJT Common Emitter Large (or bias) and Small Amplifier Circuits. My question is I could not find a decent sufficient resource neither from youtube nor from google. :( I want to study about those common emitter large & small signal models, analysis, ac gain, input &...
12. ### Peavey Centurion Mark III head with high DC voltage output

Hello, I have a 1980 Peavey Centurion Mark III head that was buried in my garage unused for 15 years. I knew it had problems (it's not mine, i got it from a friend who was throwing it) so before doing something i checked all the components and everything looked great. Once done I plugged it to...
13. ### What SMD component is this?

This is from an adblue ecu circuit for Citroen/ Peugeot cars. I need help identifying these components. Thanks for all your replies! The first one has 3 pins with the letters CG and a Y that's horizontal (on another board it shows CG with a U that's horizontal). The second one that's...
14. ### Problem with transistor

Hello, in the following image you can see a circuit with a npn transistor. I marked the given values with red and the unknown with blue. Below the circuit you can see my calculations and solutions. I'm stuck at finding I1. I would be very thankful for some guidance.

Please can anyone help me determine what type and model of transistor this psu uses(voltage, amp, etc), the one it had were removed and I have no idea what Trans use D:
16. ### Depletion mode MOSFET

Since the depletion type or depletion mode mosfet is "normally close", does it mean it does not require any gate voltage to "turn ON"? i.e current can flow in the drain-source circuit easily without any gate turn on voltage. And hence no threshold voltage is applicable?
17. ### How am I going to do this?

Hello, I have been looking for a solution for my abs lamp in my car. Now, this might not be car site or something like that but it is somewhat related to this site. Here is the problem: When I am starting my car, abs lamp should be on for a few seconds and than off. The only problem is that...
18. ### Biasing the push-pull follower to eliminate distortion

Could anyone please explain me the circuit? Especially the role of the 100 ohm resistor. In addition, which of the transistors conducts in positive and negative input? Thank you.
19. ### Design of 8-bit shift register

Hi! I'm a student of Electric Engineering and I got a problem on a Electronic project. I have to make an 8-bit shift register with serial input and serial output. The basics of the project is that it has to have two push buttons: one will be a logic 1 and the other a logic 0. The shift register...
20. ### Help with PNP-Based SPDT Switch with 'Off'

Hey everyone, As part of a larger project I need a circuit that functions like a SPDT relay, but also need an 'OFF' position. It is a rather complex application but, to explain it simply, I have a switch that has two solenoids attached to it. One solenoid moves it 'on' and the other moves...