# All Questions

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### 12 v xbox connection

Hi again if I just want to connect my tv and x box360 to the mains I've got it connected to the van at no so the neg is to the body and pos is by the fuse box. Can I just wire the transformer neg to ...
6 views

### solenoid Current controller circuit using op amp & schmitt trigger circuit

solenoid current controller Can anybody tell me the working of this circuit,eg.frequency of first op amp,for input supply of from 17V to 60Vdc how the current through the solenoid is maintain ...
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### How can I emulate two analog joysticks (potentiometers) with an Arduino?

I have a quadcopter (Syma X5C) that I really want to control with an Arduino. Since I have the ability to write programs to my Arduino to make the quadcopter fly autonomously, I want to modify my ...
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### I want to attenuate my incoming signal whose value is around (+ -) 80V to (+ -) 0.8V

I have used this circuit configuration to attenuate the signal..will this work without clipping the signal..? is there any alternative to this..I have to give signal to ADC as a input whose input ...
11 views

### Check me on this modulation question?

I need to check my answers for parts (a) and (c); a) I got q(t) = p(t)cos(5pit) c) i got y(t) as a rectangle with amplitude 1 from -pi to pi. So, y(t) = 1/8 f(t) Am I correct for both parts;
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### Power Transistor Help

I'm looking to switch an 18v signal at 1 amp with a N-Channel power MOSFET with at least 1.5v to turn it on in a TO-220 package but unfortunately I've only been able to find this one from Fairchild: ...
18 views

### Altium polygon pour doesn't cover same net pads

I've made boards and seen more that use polygon pours that flow over pads that connect to the same net. However, I was tasked with making minor changes to an old board that I didn't design. On the ...
12 views

### reception with out interrupt in usart of pic18

I would like to know how to receive data with out interrupts in the pic18 controller. After setting the Usart settings and baud rating what things must be done so that Usart receives properly with out ...
21 views

### USB max devices for host and hub

I am new to USB. I am studying the USB in a Nutshell Guide and the relevant parts of the USB2.0 spec. As per what I have read, a max of 127 devices can be connected to a single bus. As only one host ...
21 views

### Converting a 10A supply into a 16A appliance [on hold]

Is it possible to insert a converter between regular 10A 240V mains supply that would be capable of running a tool rated at 16A, 3500W? Obviously, the tool won't run to it's full capacity but could ...
24 views

### MIDI To Polyphonic Square Wave on Arduino

I've been struggling with this for a few days now, and I would really like to get on with my project. Unfortunately this is holding me up. What I am trying to do is retrieve MIDI signals sent over USB ...
29 views

### SCR triggering and ground loop issues

I am trying to trigger an scr/thyristor from a 0-5V TTL pulse (channel 1 on the oscilloscope output). The schematic can be viewed below. I am using the TTL to pull the 2n2222 transistor 'on' which ...
119 views

### Flash memory: Does the entire page need to be erased before writing just a few bytes?

An easy question, I hope! I'm not finding any definitive answers... I'm writing drivers for a SST25VF064C flash memory chip. It communicates via SPI. Like all flash memory (that I know of), it ...
34 views

### Is it safe to use a bus buffer as level shifter?

I am currently using SN74ABT5402ADW as a buffer and level shifter for my ADC, however, the datasheet does not explicitly say that it can be used as a level shifter. I provide it with 5V power, but the ...
228 views

### Why are there so many resistors in a typical schematic?

I know that some resistors cause pull-up or pull-down or work as a voltage divider and/or current divider. But sometimes I cannot understand their function in some simple circuits: Take this motor ...
16 views

### Network theory: equivalence of cut-set analysis and Kirchoff's laws

I am interested in the proof of equivalence of cut-set analysis and Kirchoff's laws. Through online research, I am unable to find a reference for that. Can you please guide me to that?
26 views

### E51A818 = 1N5818?

I have a DeWalt DW9116 charger with a fried diode. This was caused by reverse polarity connection to a battery. It has numbers E51A818 printed on it. The only diodes I can find with 818 in their ...
62 views

### Measure 230V mains with 300V CAT II probe?

I need to measure harmonic distortions on a 230V 50Hz AC mains circuit. The Tektronix P2220 probes I have for my scope are rated for 300V CAT II when set to 10X impedance. Are these probes safe to use ...
82 views

### Solid state circuit to charge caps in parallel then discharge in series?

Do there exist a solid state design circuit to do the following: Charge multiple capacitors in parallel for a certain amount of time from a low voltage DC source, then disconnect them completely from ...
60 views

### Create poolball patterns with LEDs on snooker (pool / billiards) table

I'm building a system which places dots on a snooker (pool/ billiards) table for where the balls should be placed, how can I obtain colours like brown and black from LEDs? Is the best approach to use ...
53 views

### C# & CCS File Transfer

I need to send/receive files from/to SerialPort and MSP430F5438A, by clicking a browse button in C# interface, selecting a file (like text, notepad, etc.), and in receive case, to save the file which ...
29 views

### Sharing Clock and Data for 74HC595 and CD4021B Shift Registers?

Can output shift registers (74HC595) and input shift registers (CD4021B) share the same clock and data lines on Arduino using SPI, with different latch pins "activating" either chain for input or ...
23 views

### Cascading LM300 series VRs?

Would it be ok or efficient to reduce a 44 volt-out transformer to 17 volts DC through an LM338T then again through an LM350T to output 9.5 volts DC so I can use an 4700uF 25 volt electrolytic ...
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### ELAN microcontroller programming

I am new to ELAN microcontrollers , I am trying to program EM78P156N using UWTR from ELAN. I am facing problems as I do not know the correct procedure to program ELAN controllers. Can anybody please ...
53 views

### Phase Shifter: why is simple RC circuit's output 0 when phase is 90 deg?

I am rereading an electronics book (Fundamentals of Electric Circuits; Alexander) that says that the circuits or have the total impedance Z = R + jXc and that the phase shift is given by ...
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### Amplifier design

I am having trouble calculating values for this audio amplifier. Input comes from AVR PWM operating at 44.1 kHz with high being at 3.3V. The speaker is 8 Ohm and speced for 1 Watt. First two ...
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### Clock domain crossing timing constraints for Altera

I have a slight problem with my clock domain crossing timing constraints. I have two clock groups set_clock_groups -asynchronous -group {clk_A} -group {clk_B} ...
19 views

### Speed and Position Control for high-volt Elektro Motor with AVR

Is there anything that one can purchase to control speed and position of a high voltage electro motor? I am quite a bit of a noob at this but I could think of a circuit using photo-sensors or ...
35 views

### Elements of an AC expression

I am doing some coursework and research on AC theory and currently exploring the below expression: $$V= 100sin(100\pi t) + 60sin(300 \pi t - \pi/2) + 30sin(600 \pi t + \pi/2)$$ I need to find the: ...
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### AVR - ATmega16 - Timer config

Trying to figure out the timer setup in Atmel Studio 6 for an ATmega16 microcontroller. And I just don't get it. I am trying to create a TickCount similar to GetTickCount() Retrieves the number of ...
39 views

### Is skin effect applicable to pulsed DC systems?

Unlike AC, the direction of DC never changes. If the current varies with time, should there be enough variation in the magnetic field to cause redistribution of the current?
53 views

### Intel Atom development board [on hold]

What do people use to evaluate new Intel Atom processors? I'm looking for a board that comes with XDP headers so the development process has some visibility to it. There were a few boards on Intel's ...
21 views

### Combine two signals of different frequencies in a test setup

I have a device that is powered from a current source. The current source supplies 10A at 60Hz - the magnitude is roughly 5-10VPP. I would like to inject another signal on top of that to simulate ...
35 views

### SPI communication - bits per second vs Hz

I have been reading more and more about bandwidths and frequencies to try to solve the following problem, but I am only ending up more confused. (I have limited electrical/signals background.) I ...
17 views

### Drivers rquired for GSM module [on hold]

I'm woking on a GSM module which has a serial port. I'm using a TTL converter to convert it into USB to the laptop. the software I am using is terminal but I'm unable to select the port in the ...
19 views

### Texas Tiva Power On

I am attempting to power on a Texas Tiva TM4C123GH6PM with an external power supplied by the VCC pin from a generic ESC. In the board, there is a non-soldered pin named VBUS which I wonder is ...
69 views

### Measuring Remaining Battery Life

I am working on a project testing alkaline batteries and need a way to quickly measure remaining battery life. I would like to be able to estimate mA-h remaining in the battery. If I measure mA-h over ...
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### Importing 3rd Party Models into LTSpice

I'm new to LTSpice but have the basics figured out (laying out a schematic, setting up simulation, running) and have done so with the basic but very well stocked library included. Of course my issue ...
35 views

### Good volts and amps but phone still charging slowly

I am really new to the EE game and am still tinkering. I have built my own portable DC power source similar to a Minty Boost from scratch and plugged it into the USB port of my Galaxy S3 and it ...
52 views

### Diode rectification on a device

I have a Peltier (TEC) module, with diodes in series with each lead. (see image below) I'm not quite sure what the specs are for the diode, but it says 130 on one line and SB560 on another, so I ...
22 views

### How do you run the code without external computer in BeagleBone Black just by powering it?

For example, an autonomous robot. The code should execute once I apply the power supply to BeagleBone Black without having it connected to the computer.
22 views

### Signal from function generator to microchip [on hold]

I am trying to transfer signal from function generator to micro-chip. Before, I soldered the wires connected to the function generator to the electrodes on the chip. I wonder if I can use probe or ...
21 views

### Reluctance of torus shaped iron core with embedded wire loop [migrated]

Imagine a circular wire loop (r = 50mm), the wire has an assumed diameter of zero, which is embedded in a torus shaped iron core with a circular cross-section of R = 10mm. A current in that loop ...
44 views

### How do I reset an FPGA development board to its factory settings?

I have programmed an Altera board in configuration mode so that it runs my program when booted up. Now I want to revert it back to factory configuration. How do I do that?
54 views

### Simpler ways to generate a negative voltage?

I was in need of negative voltage to generate a ramp signal. But I am using the single supply. I tried to generate negative voltage using the DC-DC converter, but I felt it is quite an expensive ...
169 views

### Can an oscilloscope add a frequency component to my signal?

I want to check the spectrum of a DDS signal ("pure" sinewave) for undesired frequency components. The way I am doing it is by storing the waveform from a 2GS/s oscilloscope (Agilent DSO81204) and ...
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### Rated capacitor current

What does "rated current" refers to in the capacitor data sheet? Is the current that the capacitor can supply? I always assumed that it is the current that the capacitor can source. Is that correct? ...
52 views

### Circuit to pass voltages above a threshold level

I have a sine wave signal centered around 2.5 volts (1/2 Vcc) in which I require the the upper half only, brought down to 0 volts, so a 2 volt peak-to-peak input around 2.5V would become a half sine ...