Hello all,
I recently ordered a 40.7125MHz crystal to make an oscillator, but I can't get it to resonate at that frequency. I first tried a simple Colpitts configuration, and it was oscillating at 1/3 the frequency. I then tried a circuit with a cap between the base and the emitter, and a tank...
Does anyone know how to simulate a colpitts oscillator on PSpice? I'm modeling the crystal with a cap and an inductor in series and both of them in parrallel with a cap but can't get it to oscillate at all. They told me to kick start it by introducing some noise by adding a VPulse source at the...
Hello all,
I'm currently working on re-designing a keyless entry system for a car to maximize its range. Right now I'm concentrating on the design of the antenna. The current system seems to have a simple brass, top loaded monople. The frequency is 315 MHz and the antenna has to fit in a small...
Hello all,
A recently recieved a curve from a stepper motor manufacturer. It is torque (oz-in) vs. speed (rps). It also has power vs. rps on the same graph, represented by a dotted line. I thought power was torque (N-M) * Velocity(rad/s)? I do these calculations, and the power i calculate is...
I was wondering, what is the easiest way to measure torque on a 1hp dc motor?
I looked on their web site, and the motor manufacturer didn't have torque vs. speed curves. All they had was something like:
Torque(in-lbs): 0 35 70
Current(Amps): 2.35...
Hello all,
I have been given the task to find the motor that works best as a generator. By best I mean as far as efficiency and output power go at the lowest rpm possible. I have set up a small experiment to test a pm dc motor,a stepper and a dc brushless. I know my experiment has quite...
Hello all,
I am having trouble finding a motor that can be used to power up a propeller to about 12 rpm then shut off and act as a generator with the propeller being driven by an underwater current. The obvious problem here is though we have a lot of torque, what motor can generate any...
