Amplifier Definition and 544 Threads

Hi I am struggling to answer this question: The input coupling circuit of the amplifier shown in the figure consist of an RC network, with R = 1 kW and C = 5mF fed by a sinusoidal voltage source of r.m.s. amplitude of 200 mV. Assuming that the input impedance of the amplifier is, at all...

Homework Statement I am to construct a circuit which can provide variable gain for the bass, midrange, and treble frequencies of an input. One of the stipulations is that I should use as few elements as possible. Homework Equations n/a The Attempt at a Solution Right now the only...

Hi everyone, I'm new to this forum. I'm working on a senior project where we are using ultrasonic transducers at very high frequencies. Problem is we only have some weaker 25V power supplies to drive the transducers. To fix this problem we were going to purchase a power amplifier but due to...

Homework Statement Look up the offset current for the LM353 op-amp and predict the time rate of change of the output for the circuit below after the switch opens. (Find dVo/dt) Homework Equations offset current = 50 pA i+ = i-, ideally v+ = v-, ideallyThe Attempt at a Solution I really don't...

hi, sorry my English isn't perfect but please try to understand : my teacher gave me a project in which i have to use a small dc motor,op amp,and a "servo amplifier" to control the rotation of the shaft of the motor, so can you tell me what is the servo amplifier? and how to use it to control...

There are a couple of things I don't understand about the DA in general and when we use it in the common mode in particular (same input ac voltage to both input terminals). I am using Electronic Circuit and Theory by Louis Nashelsky and Robert Boylstad (p.591 for DA). When we set the...

Hie. I would like to know anyone who knows or have idea on design static and dynamic model for Semiconductor Optical Amplifier? Currently my lecturer ask me to design using Optisystem software which I quit blur on designing this models. Anyone who knows and help me please. Thanks in advanced..

Hi Does anyone know of any dependencies for op amps? for example: does it have a temperature dependence?

i had to do a study using a summing amplifier to see if the results i got agreed with theory, the answers i got was something like 9.62, the answer i should of got was 10, now this doesn't seem that far away, BUT the errors didnt agree at all, they only agreed within 4 standard errors, so i was...

Hi, could you explain me polarization dependence of SOA amplifiers. and how to transfer the transverse electric (TE) mode to transverse magnetic (TM) mode. Are there any passive components to do it?

Capacitors in "Common Emitter Amplifier" Circuit ? Should i use Capacitors in "Common Emitter Amplifier" ( CEA ) Circuit ? As i saw many CEA circuits designed without any capacitors there ! And also hear that it's better to use two capacitors, one after the Voltage Source ( that feeds the...

Is it still a high pass amplifier if C and R1 are in parallel? http://commons.wikimedia.org/wiki/Image:High-pass_active_filter.png

How the voltage gain of the amplifier depends on the frequency of ac signal. please explain. what is the role of coupling capacitors? how voltage gain is effected in mid , high and low frequency range? thanks.

http://cn.arxiv.org/ftp/arxiv/papers/0811/0811.0357.pdf The Pseudo Radiation Energy Amplifier (PREA) and the mean earth’s ground temperature Ahmed Boucenna Laboratoire DAC, Département de Physique Faculté des Sciences, Université Ferhat Abbas, 19 000 Sétif, Algeria...

hi guys, i'm doing the testing amplifier for my DIY project, and i using LM386 IC, i found that is a lot of noise at the output. i saw an example putting a capacitor at the output to reduce the noise, it work! the value of capacitor is 47uF. it not work well for other value capacitor. But...

Homework Statement http://i36.tinypic.com/hugkyb.jpg Homework Equations According to my book, if R3 = R2 and R4 = R1, I can use the following formula: Vo = (R2/R1)(V2 - V1). The Attempt at a Solution We want R2/R1 to equal 5. This means that R3 and R2 must be 5*3,3 = 16.5...

http://i454.photobucket.com/albums/qq261/integralx2/opamp1.jpg I don't understand why they did something. I found output voltage to be -1.25v , but to find voltage across the 10k resistor, its (Va-Vo)/10k am i correct? cause when i do this and try to calculate the answer for Io its not right...

1.My text says 'most of the op-amps use differential amplifier as the input stage.The two transistors must be biased correctly.But it is not possible to get exact matching of two transistors.Thus the input terminals which are the base terminals of the transistors do conduct small dc current'. I...

Hi, i want to know if there is a possibility to add a remote volume control to this amplifier above. I just have to control the volume of both channels. The buttons themselves don't have to move, just the power should go up and down by the remote. Please let me know if anyone has an idea...

Hi I was just wondering what the nodal voltage Vb would be if you shorted the 1k resistor shown in this pic: http://img401.imageshack.us/my.php?image=opampem4.jpg also with that resistor in place what would the nodal voltage Vb be? i get 90.1mV ty in advance

Homework Statement Design a noninverting voltage amplifier which can be varied between 1 and 100 capable of driving a 10 K load to +5V at a frequency of 1KHz. Homework Equations 1. In order to vary the gain should R1 and R2 be 100k potentiometers? Is there another way? 2. For a gain...

In the midband region the voltage is constant and is assumed to be unity and the transistor amplifier is always used in this region. Doesn’t that mean that there is no voltage gain??

Hi. I'm not actually doing an electronics course (Maths & Physics), but I have just finished building a 140W BJT guitar power amplifier and cabinet. I'm looking to build a FET-FET cascode preamplifier now, but am not too familiar with JFETs - So far, I've got: V+ | Resistor | JFET2...

Hi, I have project to design a device that measures the temperature of the brain first and then heats the blood to normal tempearture. it is used to treat hypothermia. In hypothermia, temperature of the blood drops down. i have designed a circuit for it. I have attached the pic. It is a...

Can somebody help me to find this kind of circuit.im really appreciete your help Specification Only one bjt,one opamp ua741 and asingle power supply of 12v must be used. A 10k ohm load and an input signal will be connected via capacitors to the amplifier. The max voltage gain is about...

Hello people I am trying to revise for my exam next week..I have searched everywhere but still I can't find how to calculate input resistance,stage input resistance and output resistance of a class A common emitter amplifier. any help will be highly appreciated. mathslova

Homework Statement 1. Calculate Vcc and Vee(should be around 14-16). 2. Calculate the input resistance. (You should get a high value). 3. Determine the voltage gain. No calculation is needed. http://img210.imageshack.us/my.php?image=effectampqe2.jpg Ucesat = 1 V Poutmax = 10 W Rl...

At a time when pc's come with microprocessors clocked at frequencies of the order of 4 GHz, it must be possible to drive a D/A converter at microwave frequencies. Anyone know of hardware to do this? Anyone know of suitable hardware to transmit the waveform at a power density comparable...

i designed an crystal oscillator of 1MHz using MC14069 ic and now i need the design of a power amplifier circuit to increase the power of the 1MHz carrier wave...can somebody help me with this!

Homework Statement How can the open loop voltage gain of an operational amplifier with AC input voltage be determined experimentally? Supply voltage for op amp is +9V. Homework Equations The Attempt at a Solution I'm really stuck here. I would appreciate some outline of...

Hey guys, I am curious on how to set up a 2 stage JFET amplifier. I've reviewed some analysis on 2 stage BJT amplifiers as well as 2 stage BJT/JFET amplifiers but I cannot find anything on how to use 2 JFETs. Any help would be greatly appreciated. Thank you!

Hi, I'm working on a project with a colleague involving amplifying some simple sine waves (20kHz) using an APEX Microtech Power Amplifier PA50 Two power supplies INSTEK SPS-3610 are connected in series and are supplying the amplifier with +/- 20 volts each. Each power supply can provide...

Good evening. Right. My question is one of a simple nature, I think. Anyways, consider the following non-inverting Op-Amp design: http://www.freewebs.com/mushg/FWThumbnails/OpAmp.bmp Now, the basic formula for any non-inverting opamp is of course \frac{V_{O}}{V_{S}} = 1 +...

hi for every one I am a new member in tis site. I hope from u to help my I have a hmoework so I want some help The question is What is the source of noise in amplifier & how can treat the noise? Thank u

hi i am using a lockin amplifier for the 1st time other than a canned college lab demo. i have a 5mV signal from a strain gage that is driven with 10Vpp at 1kHz or whatever i choose. the 5mV is increased to 5.01mV when i add some weight to the arm the gage is weighing. i wanted to increase...

Is it possible to build an IR amplifier? I have a weak remote aimed a TV really far away. Is it possible to build a device that I aim the remote at, and it amplifies the signal, then sends a copy of the amplified signal to the TV? Pretty much a repeater? If so, how? Thanks

Homework Statement An amplifier has negative feedback applied to it such that feedback fraction is 0.5%. If the open loops gain of the amplifier is 10^5 what is the closed loop gain? I get this as 199.6 The amplifier is connected to a signal source of internal resistance 300kohms which...

Hi, I need some help with a push pull design. As a project , I am doing a audio cross over. The problem I have is that I cannot find a way to drive enough current into the speakers. For one speaker, the input current is 0.02 [A] and after the push=pull amplifier, I need to be able the...

Alright, I've been stuck on this problem for my electronics class for far too long. " Design a CE amplifier with a gain of 10 using a 2n3906 transistor and a 20 V power supply. Calculate the required resistor and capacitor values for the circuit, assuming a minimum frequency of 10 Hz." It...

Hi guys, I need to build a REALLY simple amp for a friend. I only want to use a resistor and a transistor plus the normal stuff(battery and speaker). Please help. Thanks in advance, Circuit Man

Hello guys, Introduction: I would like to get some input about some kind of temperature amplifier. What I have, is: - an electrical heater (basically a resistor that is heating a square piece (20x20 mm, 50-100 W) of copper). It's insulated on 5 sides of the copper cube. Only one side is...

Hi, I'm designing an amplifier and need help with some basic ideas (Filtering is already taken care of). My main question is bolded. The output is an audio signal, and it drives an 8 ohm speaker. The power is 1 watt through this speaker. The input signal is coming from another amplifier...

Hi, Could someone please help me with something i need to know to complete my college course? The question says: 'Show with the aid of a circuit diagram and input/output waveforms how and NPN transistor can be used as a small signal amplifier, when operating in a common emitter...

hi... can anyone help with the problem i attached thanks in advance... I think a good start would be to convert the current source into a voltage source

Hello Guys, I really need some help with this one. I'm still working on the circuit design for this AD9959 programmable pulse generator and I found (from reading the datasheet) that the output from the DAC uses differential current output and not voltage output (something like 0.5V @ 20 mA...

Homework Statement We have a filtered amplifier (diagram is attached). We do not know Cf or Rf. We know that: 1 volt input at 5 Hz = 9.25 volt output 1 volt input at 200 Hz = 6.77 volt output 1 volt input at 500 Hz = 3.66 volt output Homework Equations The transfer function for...

Is there a limit to the possible amplification of Short Wave radio transmission and/or reception? A friend of mine wants to build a massive amplifier / transmitter. If a limit does exist what is the physical law used to explain it?

I've got a sony home theater system and my dvd player has gone for repairs. I've got a party to throw by tomorrow and I need some help. I want to connect my IPod to the HT system. The only problem is, it takes those individual inputs for the left and right audio signals (red and white wires)...

http://www.vcaa.vic.edu.au/vce/studies/physics/pastexams/physicspilot12004.pdf Page 13. AC signal on CRO. Answer is B. How the heck do they do that? Relevant information is on page before. Love peoples explanations but please try to keep it simple. Sorry if i seem direct. I don't...

My year 12 exams are in 1 week exactly and I'm worried about a question (from last year's exam) that my teacher can't even answer. Each year they tend to repeat the difficult questions, and this was one of those. I'll just give a summary of the question, and maybe you'll be able to answer my...