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-2
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0answers
27 views

GPS tracking for valuables [on hold]

What type of specific engineer is used to develop a micro gps or similar tracking device?
-1
votes
0answers
7 views

Node Analysis Q find I knot using node analysis?

Im stuck in this question. I've solved it using mesh analysis but in the question it's written only to solve using node analysis. Q Find the value of I knot (I.). Picture of circuit given below
0
votes
3answers
50 views

Power switch placement

When building a circuit, are there any conventions as to where the on/off switch should pe placed? As in between the negative pin of the battery and ground, or between the positive pin of the battery ...
0
votes
1answer
17 views

What does splitter do in logisim?

I have just started learning logisim, so i have a very simple question. My question is what does splitter do. Whats its function and how can we actually implement it(like on breadboard or trainer ...
0
votes
0answers
42 views

how i powered an LED with 220 AC [duplicate]

can anyone suggest a simple circuit which lights up an LED with 220V AC. I am trying to make something without the use of transformers. Maybe a bridge rectifier and a resistance connected with LED. ...
3
votes
2answers
164 views

How to create a frequency doubler circuit using only flipflops/ Digital elements?

First things first, is it even possible to scale up the frequency using only digital elements, atleast approximately? Though a frequency divider circuit can be designed very easily with flipflops. In ...
1
vote
3answers
154 views

Only one LED is working on this traffic light circuit

I have a problem with my traffic light circuit. I've made sure of the wiring and everything seems right but for some reason only the yellow LED is lit constantly without it flashing and the other 2 ...
-4
votes
2answers
79 views

elevator algorithm circuit [on hold]

I'm trying to make a electirc circuit that features an elevator algorithm. It has five floors and I can only use resistor, capacitor, ua471 (op-amp) and switches. Please help
1
vote
1answer
47 views

How do you design a circuit to implement the Bipolar Line coding Technique?

Bipolar NRZ http://www.tutorialspoint.com/data_communication_computer_network/images/bipolar.jpg In this technique alternate 1's will have alternate polarities and 0's will be zero itself.
-6
votes
1answer
71 views

My Circuit is leaking voltage. What diodes\methods can I use to fix this problem [on hold]

Okay so here's the deal I am using these items in parallel to power one load in order to supply enough current (3A max) at a constant 5V. I won't get into detail about why exactly I'm using ...
-3
votes
3answers
101 views

may i know what is wrong in this circuit?.. forward-reverse motor

what is wrong in this circuit this is a circuit for a forward-reverse motor.. what is wrong on this?? I made it on PCB board and it doesn't work!!
-2
votes
1answer
53 views

MOSFET Circuit: Bypass capacitor

Does anyone know how a Bypass Capacitor work in it's physical operation? How does a bypass capacitor filter out the ac signal in the device structure and physical operation?
0
votes
1answer
30 views

How to define a primitive device in Proteus?

I'm trying to make my own full adder and some other devices as a sub-circuit in "Proteus" and use them several times in a bigger circuit. The problem is when you copy a sub-circuit you need to rename ...
0
votes
2answers
241 views

Designing an 8 x 3 memory chip given 2 4 x 3 chips

I'm working on a problem that asks me to design an 8 x 3 memory chip given 2 4 x 3 memory chips. I'm not sure how to approach this problem. I've looked at the textbook and found various online ...
0
votes
1answer
39 views

Determine a resistor's value in a circuit with an N-type MOS-FET transistor

In a circuit involving an N-type MOS-FET I am to determine the value of resistor \$R_2\$ Now in order to solve this I need to know what \$V_{DD}\$ represents, is that the voltage relative to node D ...
1
vote
1answer
73 views

Which one is the better way to feed analog input to my ADC?

I am planning to use an AD7730L analogue to digital converter (ADC) chip, with a quarter bridge circuit. Everything was on the track until I realised something, which indicated that things were ...
0
votes
1answer
114 views

What runs a g-shock watch?

I am currently trying to learn more about watches and what it takes to build them. I currently own a watch called the G-Shock 7900b and was wondering what runs it inside. Here is a link to the watch: ...
0
votes
1answer
37 views

Determine I through load resistor in circuit with diodes in series

I'm trying to find an expression for the current through the resistor \$R\$ when the AC-source is at max voltage of 5 volts. \$U_T\$ represents the voltage drop across each diode. \$R_D\$ represents ...
-1
votes
1answer
47 views

How to reverse the direction of operation of the motor?

For Synchronous buck, half bridge converter, how to reverse the direction of operation of the motor? That would be great if you could explain me with the circuit diagram.
0
votes
0answers
37 views

Can someone demonstrate the passivity property of a RC circuit?

Intuitively, a RC circuit is considered a passive element because it does not require power to operate as contrast to Op-Amps. But the passivity property is most precisely defined via the mathematical ...
0
votes
0answers
16 views

Finding the State Table for a Synchronous Sequential Circuit

I'm learning about circuits in my ECE class and want to make sure that I have the correct table. I am working with D flip-flops and T flip-flops in this circuit. I want to make sure that I have the ...
-1
votes
0answers
31 views

what is the deference between pnp transitors references?

I have a a simple question, what is the difference between PNP transistors? How can I choose my PNP transistor reference so that I can build my circuit? The problem is there are a lot of PNP ...
2
votes
1answer
41 views

is the drawn diagram right for detecting a sequence of three or more 1's?

i saw this diagram in my textbook for the problem : Suppose we wish to design a circuit that detects a sequence of three or more consecutive 1ā€™s in a string of bits coming through an input line ...
1
vote
1answer
51 views

Issue with RC op-amp oscillator

I'm trying to understand how oscillators work and am currently working with an RC phase shift oscillator: $$R_1, R_2, R_3 = 200 \Omega$$ $$C_1, C_2, C_3 = 4.7nF$$ one of the issues I'm having is ...
1
vote
2answers
345 views

How to figure out which transistor amplifies the signal?

Suppose I have the following circuit: How can I determine which transistor amplifies the signal and which transistor is just a simple resistor? Also if is a resistor how can I determine it's ...
4
votes
4answers
169 views

Transfer Function for a combination of filters

simulate this circuit – Schematic created using CircuitLab I am currently working on trying to determine the transfer function for the audio tone circuit pictured. $$R_1 = t \times ...
0
votes
0answers
38 views

How to implement the bit count using logic circuit?

I am very interesting in these bit counting problems, since there are many programming implementations such as: http://gurmeet.net/puzzles/fast-bit-counting-routines/ Also someone discussed the ...
0
votes
0answers
65 views

What circuit can I use to replace an ideal current source?

I have a circuit that has the following topology: The current source is providing 46.5uA, and the node voltage of the current source is shown. I know that current mirrors are usually used to ...
0
votes
1answer
38 views

Getting bad clipping issues with this 3 stage amplifier

What am I using? 3 stages of amplification. An input voltage of 10mV peak or 20mV pkpk into the first stage. 1st stage: NJFET Common Source. Using a voltage gain of 3. 2nd stage: NPN BJT Emitter ...
1
vote
2answers
274 views

What are the “No Connect” terminals on this multiplexer and what purpose do they serve?

I was looking through the datasheet for the ADG506A/ADG507A and on the chip there are these terminal marked as NC and underneath the image it says "NC = NO CONNECT". They are also not explained in the ...
0
votes
1answer
40 views

Finding V(l) for t>0 in RL circuit

One of my problems asks me to find the voltage at time greater than zero. The first part of the question asked me to find current. I was able to solve that part and found it using the general solution ...
-1
votes
1answer
56 views

Calculate a function with logic gates

I have to build a circuit, with logic gates, that calculates a function \$f(n) = 2^{2^n}\$ where n is a 4 bit number. I can't figure a way how to do this. I tried to use 2-to-4 decoders but I failed. ...
0
votes
1answer
47 views

finding I(current)

I am learning about step response in RC and RL circuits and one of the problems i managed to redraw as the image above; however, when I am solving for i the answer is -5mA. I am just confused on why ...
0
votes
2answers
72 views

How to analyse this diode circuit

what will be the voltage at Vx if D1 and D2 are practical diodes This is not a problem from some text book. This circuit came in my mind while i was studying differential amplifiers.
-4
votes
1answer
77 views

Difference Between LM386 and LM741 [closed]

What is the Difference Between the Normal Opamp LM741 and the Audio Power amplifier LM386.. I mean in both the circuit we use the concept of voltage compensation, then how come LM386 is called power ...
0
votes
2answers
46 views

Constand output voltage from batteries / rechargable batteries

I'm trying to make myself a battery pack for my DSLR camera. The original battery of the camera has 7.2 V and 1200 mAh. I've also bought a coupler ( a dummy batterie for external DC input ) which ...
0
votes
0answers
67 views

Can't figure out circuit analysis

The original homework problem is as follows: I have the solution from the professor, but I don't understand why he rewrites the model the way he does, and I also don't understand the derivation of ...
1
vote
2answers
74 views

Grounding a wire using a chunk of metal?

So I've made a complex LED grid and it works but has ghosting in some of the rows. I've given up trying to work out the reason why, but have noticed that when I touch the SCLK wire, or connect the ...
2
votes
1answer
44 views

Simple RC-Circuit (Neuron): get \$u(t)\$ as a function of time

I am trying to understand how a LIF-Neuron (please take a look) works and how I come from this: \$ I(t) = \frac{u(t)}{R} + C \frac{du}{dt} \$ by multiplying the equation by \$R\$ and call \$\tau_m = ...
0
votes
2answers
122 views

brief explanation of Ohm's law

How can I calculate ideal values of current for both short and open circuits by using Ohm's law. Further more usually said that it is not advisable to connect DC batteries of different voltages in ...
0
votes
1answer
34 views

designing a sequential circuit by having it's value table?

when learning about combinational circuits we could draw the truth table and construct a circuit by the help of min/MAX terms . and we could further simplify it with Karnaugh maps . BUT how we do ...
-5
votes
2answers
96 views

Can anyone identify this?

Can anyone tell me what these ports are for, or what they do?
1
vote
1answer
38 views

4 pole to 3.5mm female

I have a circuit board I took from a broken wireless headset, and I plan of reusing it by soldering a 3.5mm plug to where the speakers was connected. So I could plugin whatever headset I want. But ...
0
votes
2answers
63 views

Timing circuit with op amps and capacitors

I understand how a basic comparator op amp works and how a capacitor charges individually, but I can't seem to put it all together to make this circuit. I think I might be messing up with the voltage ...
0
votes
1answer
81 views

2.2K Resistors on Microchip Data Input Lines [duplicate]

I've just been dabbling for the first time into circuit design with microchips and I noticed a lot of designs put 2.2K or 4.7K resistors on some input lines. I get that this is to limit the ...
0
votes
0answers
37 views

Need help about the sign conventions used for voltages in the ckt

What are the significance of the sign convention of the voltage drops shown in the ckt. Vo = Initial charge of the capacitor
0
votes
3answers
120 views

**Solved** D Flip Flop Frequency Divider - Simulates but doesn't work on protoboard *Pics/Simulation Data Included*

I'm having a problem that is probably trivial, but I can't seem to make any progress. Just a disclaimer, I'm an analog EE and digital design isn't my strong suite. That being said, I'm trying to build ...
0
votes
0answers
54 views

Best Way to Extend 30A 120v circuit over 300 feet? [migrated]

I have an old barn to which i'd like to provide electricity. The problem is that the barn is about 300 feet away. I understand that voltage drop over 300 feet is fairly significant. Buying thicker ...
0
votes
1answer
48 views

How to find places to add power indicator light in simple DC circuits?

I build a lot of little hobby circuits and I usually place them inside of some kind of project box. Right now I'm working on the "Atari Punk Consol" by Forrest Mimms. It looks like this: I tried ...
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votes
0answers
60 views

Trying to get a gain of -2

What capacitor will this circuit have a gain of -2 at 40 kHz? The op- amp has an open loop gain of at least 10000 at this frequency.