Pulse width modulation involves a capacitor and associated logic. When logic is applied, the capacitor is allowed to charge at one rate. When logic is applied, the capacitor is allowed to discharge at one rate. I suppose you could use a 555 timer, but isn't there an even simpler circuit if...
I don' know. Do you have the idea that this will work to a certain extent. It becomes a little tricky when you get away from the transistor model, add a 5 layer device it's even more complicated. Maybe as far as the hfe goes, it would depend on the zener conducting heavily with a small change in...
The high impedance, but able to pass the signal. You will find that the two base resistors have to be low value in order to get the base current. This makes the emitter impedance low. I needed a higher impedance for the purpose of gain.
You know that when they post a circuit with a constant current source they don't mean the inclusion of an opamp. I tend to think that the opamp configuration for a constant current source is there as an example of how one could do it if the current you need is high enough. A circuit diagram with...
The reason I thought of this is because I wanted to operate a transistor backwords in a circuit. I wanted the collector to act like an emitter. The nice thing about the collector is high impedance. The nice thing about the emitter is the ability to change the current and pass the signal. You...
I think it could be used to replace the transistor in some cases. The transistor will not change it's current with a changing collector voltage, but maybe a zener with a diode will. This is certainly a legitmate use that may act similarly to a transistor if the zener and diode were chosen...
The amperage part is going to be difficult to know. Just guess by the size of the transformer. It's interesting how high the current can be. The rated amperage is the average current and not the peak current. You will notice that a fuse is very small for the rated current, this is because it...
The capacitor filters the wave, thus changing it. The peak of the input allows for DC charging of the capacitor, then input voltage drops and you are left with the DC charge that will not drop because of the rate of change. What I had in mind is a full wave rectified sine wave whose average is...
Keep in mind that the capacitors have a specific impedance and could be replaced for resistors at the frequency you want to keep. They look like they attenuate the lower frequencies. Look at the high gain of T3. It's amazing that this is typically done with IC's when we know how unstable it is...
It does not give you the average. It gives you the peak of the voltage with ripple, which can be used for determining the average. The ripple contains the information about what happened to the filtered part. For instance, a reduced ripple would indicate a greater average.
The first thing you should do is determine the exact amount of current you will need. Use a transistor with double this current. Make a regulator with feedback. This involves a reasonable amount of circuit design. I would use a low current transistor whose emitter goes to the base of the high...
It is my opinion that we should find a way to measure waveforms without relying on an A/D process. You have to remember that even an unknown waveform can be electronically deciphered using a circuit. For instance, a full wave rectified sine wave can be filtered to give you a ripple which can be...
The triangle wave rely's soley on the DC charging of the capacitor. I would tend to use the capacitor and a transistor driven by a square wave to generate a triangle wave. The use of an opamp is not necessary.
I looked at the schematic for the inverter and am having trouble with it. The input transistor is not biased to work like a transistor and I have seen a representation of two diodes in a book. Why doesn't the schematic show these two diodes instead of the transistor?
I believe a synthesizer is just an oscillator with enough added to make it variable. I know that there are but a few major designs for oscillators like the Hartly, Colpitts, and Clapp. A synthesizer could be a variable one of these. I would be interested in any advice concerning the operation of...
I am certain that the mathematical order of operation is to square the function, integrate, then take the square root. If you have the output from the A/D, you can determine peak to peak, average, and RMS.
RMS produces the same power dissipation as it's DC equivalent. 6vrms produces the same power dissipation as 6vdc. The mathematical representation is as follows:
square the equation, integrate, then take the square root. There must be zero offset to get the result Vrms = .707Vp.
It is the job...