I built a pulse generator with some components for the local radio shack, 555 on a breadboard and ...
I tested it and it puts out a 50% duty cycle square wave. With a variable resistor I am able to control the frequency.
I want to build one where I control the duty cycle as well as the frequency.
hummm, number 2 on the 555 is the trigger, so that would be the on time trigger. #4 is the rest so that would be the off time, no, well, I do not know.
Gold star if you can make the frequency and duty cycle adjustment independent. I've never figured out a way to do that.
EDIT: I should say that I actually have made them independent. However, adjusting one affects the range of the other. I was never able to come up with something that doesn't screw with the ranges.
Gold star if you can make the frequency and duty cycle adjustment independent. I've never figured out a way to do that.
EDIT: I should say that I actually have made them independent. However, adjusting one affects the range of the other. I was never able to come up with something that doesn't screw with the ranges.
I only said that I haven't been able to do it. You can adjust the frequency independent of duty-C, but then it affects the range. The quantities are independent, the ranges are not.
Well for example, you can vary the frequency over a range, say from 10hz to 10khz. That's the range. But the particular frequency you're running at at any particular time is the quantity. As an example, maybe you have a range of 10hz to 10khz, that's the frequencies that is possible from your design. But you've adjusted your circuit, to 5k hz. That's the quantity.
I built a pulse generator with some components for the local radio shack, 555 on a breadboard and ...
I tested it and it puts out a 50% duty cycle square wave. With a variable resistor I am able to control the frequency.
I want to build one where I control the duty cycle as well as the frequency.
I have a circuit that does exactly what you want. I used two 555's so that the frequency and pulse width could be varied independently without affecting each other. The first 555 is a free running oscillator and the second is a one-shot. The oscillator triggers the one shot. You can vary the R-C timing components to get different frequencies and pulse widths.
Gold star if you can make the frequency and duty cycle adjustment independent. I've never figured out a way to do that.
EDIT: I should say that I actually have made them independent. However, adjusting one affects the range of the other. I was never able to come up with something that doesn't screw with the ranges.
The problem with that is as you adjust the frequency higher, then it becomes possible to adjust the one-shot period to a value longer than the period of the oscillator. Thus, the output frequency is affected by the DutyC adjustment.
The problem with that is as you adjust the frequency higher, then it becomes possible to adjust the one-shot period to a value longer than the period of the oscillator. Thus, the output frequency is affected by the DutyC adjustment.