Gain Definition and 417 Threads

Homework Statement Find the input impedance. Homework Equations The Attempt at a Solution Input impedance= R1. I don't get why we can ignore the other resistors. Problem 2 : Homework Statement Find the gain of the system...

Homework Statement For the differential amplifier circuit given above, for all transistors except Q1 and Q2 we have: β=100, VA=80 V, RC =20 k, VT=0.026 (Thermal voltage), VBE(on)=0.7 V a-Determine the collector currents IC1, IC2, IC3 and IC6 b-Calculate the Differential mode voltage...

I need to design a unity gain amplifier for a sample and hold circuit. I've decided to use the circuit shown in the attachment. Now I know the gain = 0.5(Gm2*R1)[(Gm3*R2)/(1 + Gm3*R2)]. The 2N7000 has a Gm of 0.1, so that gets me the values of R1 and R2. I don't know if these are good values to...

Homework Statement Beta=100,Thermal Voltage=0.026 Volts, Va=infinity, and Vbe=0.75 Volts for the differential amplifier. Please look at the upload for a clearer picture. Homework Equations Ad=betaRc/2(rpi+Rb) Acm=-gmRc/(1+(2(1+beta)Ro/(rpi+Rb))) The Attempt at a Solution I have...

how do you prove mason gain formula?

How would I determine gain and phase margins for the following transfer function: G(s) = (0.38(s^2 + 0.1s +0.55)) / (s(s+1)(s^2 + 0.6s + 0.5)) We are learning about Bode plots but I am really struggling. I know that Bode plots display the relationship between magnitude vs. frequency and...

So I have a question regarding the gain of common emitter amplifier. Referring to the attached diagram, the voltage gain of the circuit is -RC/RE. However, I don't understand how Vbb can be removed when completing the analysis. I've done the KCL analysis by hand and keep getting a gain function...

Homework Statement Problem #6 on the attachment Homework Equations The Attempt at a Solution I am stuck because if I do KCL at the node above the current source, It seems like all of the current should go back into Rs and none from the current source goes up to Rf

Homework Statement Problem statement is in the attachment HW 5, it is problem #1. Homework Equations The Attempt at a Solution I am just stuck with a whole bunch of variables and this just looks like a complete mess

Using a MVDR method for a uniformly spaced linear array of sensors, I calculated the optimal weights. The procesing gain is (SIR)out / (SIR)in . The value turned out complex. Is this possible/makes sense?

Homework Statement Problem picture is attached also some of my work is attached. The problem states derive midband voltage gain v0/vi expression in terms of circuit parameters. From the expression you just derived calculate numerically the midband gain value? Homework Equations...

Homework Statement The circuit below is a BJT common collector amplifier. Find both the voltage gain (AV = Vout / Vin) and the current gain (AI = Iout/Iin). As with Problem 1, this may seem hard to parse at first, but it is actually pretty straightforward. Carefully replace the BJT symbol...

Homework Statement Homework Equations The ratio of the parameters \frac{E_1}{E_2} to find the gain (in dB), 10\timeslog10\frac{E_1}{E_2}. "To determine the gain factor in part 8, first think about what happens to the energy when you multiply the signal by a constant factor. Then use the...

I'm currently doing a spectroscopy lab where you use a scintillator and Cs-137 to obtain a Cs-137 spectrum. I calibrated this spectrum using the known gamma energy for Cs-137 at 662 Kev at the photo peak. I am now trying to use this calibration for a Co-60 spectrum. The problem is that when I...

Homework Statement A typical transistor amplifier is shown in the Figure. Find the amplifier gain G. Circuit diagram: http://i.imgur.com/Rzv4JR7.png Vs = 280mV R1 = 100Ω R2 = 7kΩ R3 = 100Ω Vd = 4*10^5 Ib (Ib is current through R3) R4 = 7kΩ R5 = 900Ω Vo = ? (Voltage drop of R5)...

I'm currently doing a spectroscopy lab where you use a scintillator and Cs-137 to obtain a Cs-137 spectrum. I calibrated this spectrum using the known gamma energy for Cs-137 at 662 Kev at the photo peak. I am now trying to use this calibration for a Co-60 spectrum. The problem is that when I...

An amplitude of output voltage Vo of a voltage amplifier was compared to the amplitude of input voltage Vi. The ratio Vo/Vi was 200. Find the power gain in dB. Can someone explain to me how to find this? The solution is given as below, but I don't understand how can Po/Pi = 200^2

Hi. I know G_P (dB) = 10log(G_P) and G_V (dB) = 20log(G_V) and G_I (dB) = 20log(G_I). I also know that G_P (dB) = G_V (dB) + G_I (dB). So, if I have a common base amplifier whose current gain is G_I (dB) = 0, then G_P (dB) = G_V(dB). Suppose G_V (dB) = 20 dB. So G_V = 10^{20/20} = 10 G_I...

Hi, I have been reading about CERN for a while and found amazing - amongst many other things - the fact that hadrons in the LHC turn some of their energy to mass after having reached the maximum possible speed. However this statement was not clear enough. I was wondering whether the mass they...

Hello I'm a bit stuck on this. The question states that the non ideal op amp (pictured below) in open loop conditions has an input resistance of 400kΩ, an output resistance of 2kΩ and a voltage gain of 500,000. I then asks to find the voltage gain, the voltage at the negative input terminal...

I'm not sure if this question should be posted in the introductory physics section or the advanced physics section. Consider an amplifying medium, composed of homogeneous broadening four-level atoms as show in figure 26.5, page 557 of textbook. http://img689.imageshack.us/img689/6108/lt2f.png...

I know that ΔS=qrev/T for any process, but what is qrev here? It can't be identical to the q in ΔU=q+w - if it was, why don't we just write it q? The other problem is that it would mean that ΔS(surroundings)=-ΔS(system) which need not always be true. Secondly I want to derive the equation for...

Homework Statement 1) H-plane patterns of rectangular microstrip antenna, open-ended waveguide antenna and small horn antenna are measured and shown in the table below. Assuming the small horn antenna as reference antenna with a gain of G_{smallhorn} = 8dB Obtain the gains of the other two...

I have a diode laser that emits multi-mode light. Two frequencies of this light are selected in an external cavity and reflected back into the laser diode. The laser diode's gain medium then resonate at these two frequencies and emits dual mode light. The laser operates in the 1550nm region...

Homework Statement I'm trying to find a relation for the voltage gain of an emitter follower. For an emitter follower the voltage gain is given by \$A_v=\frac{r_o|| R_L}{(r_o|| R_L)+r_e}\$, where \$r_o\$ is the output resistance of the transistor and \$r_e\$ is the intrinsic resistance of...

Homework Statement The following voltages are applied to the instrumentation amplifier in the figure. Vin1=5 mV, Vin2=10 mV, and Vcm=225 mV. Determine the final output voltage. Homework Equations R_{1}=R_{2}=R A_{cl}=1+\frac{2R}{R_{G}} V_{out}=\left ( 1+\frac{2R}{R_{G}}...

In the following diff amp, only one output is taken from collector two. When I calculate the differential mode gain using the second differential input (-Vid/2) I get a positive gain. When I calculate the differential mode gain using the first differential input (Vid/2) I get a negative...

Homework Statement Find the input resistances and voltage gains for those ideal op amps Homework Equations The Attempt at a Solution The original inverting circuit look like this : we already have the equations : input resistance = 10k voltage gain = -r2/r1 = -10 For the...

My professor asked me to provide a circuit design for a voltage divider biasing circuit whereby the transistor beta is independent of the voltage gain, which he wants to be -100. I maintain this is impossible, as Ic = B*Ib, changing the beta obviously effects the gain. Right? (not...

Hi guys, I'm reading solid state physics, I have some doubts about phonons. Here is the question, if we heated up a material, based on the the thermal equilibrium of occupancy of phonons given in Kittel's Introduction to Solid State Physics, <n> = 1/(e^(\hbar\omega/kBT)-1) so as T...

Homework Statement I really need help with them all but I mostly have a question over the problems with noise margins or gain terminology. The problems are located here on tutorial problems under the digital abstraction it is the second one under tutorial problems. The problems can be found...

I am attempting to come up with a systematic way to design Multiple Feedback bandpass filters with certain specifications. • Frequency is some given number • Bandwidth varies with Frequency by f0*2^13/12 • The Q should therefore be .4719 • The gain should be 1 I am at an understanding of how...

large signal current gain hFE = (IC - ICBO)/(IB + ICBO) and small signal current gain hfe = IC/IB 1. what is the difference between these two. 2. why can't we use large signal current gain in small signal currents?? 3. i have these notes on page 57 (page 1 on pdf) paragraph 2 of these...

I came up with this question while studying for an upcoming exam. I had a design problem, my solution gave me a gain of about 5500 with a PI compensator. Does having that high of a gain screw with my system? It gives me the desired results in MATLAB, but are there any drawbacks to doing that?

I have a linear model of a phase detector (phase lock loop) represented by the block diagram below. It is designed to maintain zero difference in phase between the input carrier signal and a local voltage controlled oscillator. Phase demand→Ka→F(s)→K/s→Phase output F(s) =...

Homework Statement A satellite link has a transmitted power output of 0.5W. This power is increased in the direction of transmission by the transmitter antenna, which has a 20dB gain. The RF signal is attenuated by a path loss of 200 dB. The total noise level at the receiver input is estimated...

Hi, I was wondering what the trade-offs were in having an optical gain (say with EDFA) compared to electrical gain (say with a PIN and transimpedance amplifier) of an optical signal. Thanks.

Hello all. I am currently trying to find the gain of a 2 stage amp. According to some notes I have, it is: A = A1 x A2 x (rin2 / (rin2 + ro1)) Where A1 = gain of first stage A2 = gain of second stage rin2 = input resistance of second stage ro1 = output resistance of first stage Let p...

Should I start by learning about the equations for classical harmonic waves and how the de Brolier equations can be applied to them? What else should I learn? I'm a chemistry student and we did a class on quantum chemistry, but the mathematical side of it was way too complicated for me so I just...

Homework Statement Working through some homework problems we are given the desired gain and input resistance, and are asked to choose what type of amplifier (mosfet or bjt) and what configuration would be ideal. The solutions are given. In the solutions, and in the design example in the text...

Homework Statement THe problem statement and given solutions are in this thread: https://www.physicsforums.com/showthread.php?t=694054 I do not understand the equation for current gain: Homework Equations Ai = \alpha\frac{R4}{R4 + Ri} The Attempt at a Solution I have pages of...

Homework Statement Problem statement and solns. in attachment. Homework Equations Can anyone explain the equation for the current gain Ai? I do not understand where the divider temr comes from. The Attempt at a Solution

Homework Statement Find the differential gain int terms of small signal parameters of the attached image. Homework Equations I don't think we need any equations. Just some basic mosfet knowledge. Not going to draw the small signal circuit, because it would take a long time. The...

Homework Statement I just have to calculate midband gain for a typical NPN BJT. The transistor model is a 2N3904 Have I calculated something wrong?? My gain is 0.748

I have single 741 op amps running as unity gain amps and they work fine but when I tried to use a quad 741 op amp (LM348n) with the same config as the single 741 (short the inverting input to the Vout), the results are not correct. Can anyone provide a chip id and wiring config for a quad 741...

Homework Statement A 275 KG steel mass is held by a long cable to the ceiling. Daniel hits the steel mass horizontally and gives it a horizontal speed of 1.75 m/s. Assuming there is no friction, determine the maximum height gain, in centimetres, of the steel mass after the collision...

Hi, I have a common base amplifier circuit but I am not sure of the equation to use to calculate the voltage gain? Could someone help me please

Could a star gain more mass from elements that "collide" with it? If a ×-sized meteor crashed into the sun, does it ultimately accrete to the sun?

Homework Statement I am designing three amplifiers: 1. is an noninverting amplifier with G=200 2. is an inverting amplifier with G=-50 3. is a summing amplifier with V(out)--50V(in1)-3V(in2)-15(Vin3) all problems i(outmax)=2mA So far the only problem I have figured anything about is...

Homework Statement Hi, I've been having trouble setting up an oscilloscope, with a AC voltage supply, to a breadbox, with a "black box" in the circuit. the black box is just a set of 3 pairs of terminals, each a "unknown component" such as a diode, capacitor, resistor, etc. Basically I need...