Recent content by nylonman

Hi, I'm taking a control engineering course and I've got a little doubt about PD controllers. Here is my root locus plot: http://imageshack.us/photo/my-images/535/controlw.png/ I have the system defined by the poles in the root locus with some design specifications that are satisfied when the...

Ok, I was confused with the purpose of adding some extra bias voltage with R2. Tanks for your help.

Ok, thanks! I understand it now but there is another detail: The book says that R4 and R3 improve thermal stability since there is a voltage drop of few tenths across them that can be controlled with R2. But wouldn't it be better that there wasn't any quiescent current at all?

The emitter node can have negative voltage, notice the negative voltage source and the voltage drop across the leftmost resistor. When you calculate all the currents in the emitter node (the currents through the emitter and the two resistors) you can notice that the emitter 'sinks' current only...

I suppose that Q1 causes a variation of its collector current according to the input somewhere in the previous stage. I see that if Q1 isn't conducting at all the last stage 'pushes' current to the load (not shown here). But what about 'pulling' it? Try this link...

Hi, I'm trying to understand the operation of the schematic I attach. http://imageshack.us/photo/my-images/853/abampschematic.png/ What's the point of having the input at the Q1 collector? I can understand the more common structure shown in wikipedia (...

ok, so in other words you are saying that we need the resistor in order to discharge the capacitor since the transistor emitter allows the current to flow only in one direction, right?

ok, I see it, it was simpler than I thought. Thanks!

Hi, I'm reading The Art Of Electronics and I saw this in the emitter followers section: "Warning: You must always provide a dc path for base bias current, even if it goes only to ground... if the signal is capacitively coupled, you must provide a resistor to ground (Fig. 2.18)." Here...

I found this: http://www.cs.unm.edu/~brayer/vision/fourier.html There is an explanation in "rotation and edge effects" section.

Confusion with 2D DFT Hello everyone, I'm trying to figure out why the third transform in the picture I attach here is different to the other ones, why it's 'distorted'. I know that it's related with the fact that if you copy the image in a grid the resulting image has discontinuous lines...