Can somebody help create adjustable (10-70 Hz) LED strobo, please.
Thanks for answer, but I need with 1 or 2 withe LED (very low energy output) and I need exactly to know what kind frequency of strobe is in particular time, and I need change gradually from 10 to 70 Hz (for example 10, 12, 14, 16, .......) Thanks
I'm medical doctor and really not understand how it is working :)
Hi, Have to gargled arduino strobe
Not for gargling :) For swollowing or rectal using :)
Have a look at the blink without delay example in the IDE, and play around with it.
Really I need this strobo for diagnostic
Do you need a manual control for the rate (like a potentiometer), or does the rate ramp automatically? Is the "on" time the same as the "off" time?
Manualy and accurately
Have to gargled arduino strobe
Have to google arduino strobe
If we had more information on how it is to be used, we may come up with better ideas. At this time it is simply a variable frequency strobe.
Do you need to know the frequency? Then it requires a read out. How do you want to change the frequency? Potentiometer, buttons or automatically?
A full specification is required.
I need change frequency manually and need to know what is the frequency I put in this time. I need to put 10Hz, after that 16 or 30 or 12 (VARIABLE from 10 to 70) and I need to know what is frequency.
What about light intensity and pulse duration?
Can you use a PC terminal to input the frequency via serial? Or do you need a standalone device.
What type if use is it for? What are you testing?
Standalone device Intensity - no more than comfort visible, whet you see directly on LED. Pulse duration - 1:1 (light:dark) variable changeable duration of item working. I can discuss only technical parameters of device, not practical using. Sorry
I suggested looking at the blink without delay example - did you try playing with it?
How I can create this device?
Very, very simply - you just need to decide what features you want, and how to control and present them.
A xenon stroboscope generates a very narrow pulse of intense light, probably only a few microseconds duration. However it needs a high voltage supply, and an even higher trigger voltage, so would not be a suitable project for anyone not experienced in high voltage working.
It would be far easier to use a high powered white LED., switched by a logic level FET.
You need to convert the frequency that you require into the period of the desired waveform, this is simply calculated from the relationship :
period = 1 / frequency
For best frequency resolution use time measured in microseconds (μs). So 10Hz, becomes a period of 100000 μs,, and 70 Hz is 14286μs.
Using the technique demonstrated in the example sketch "BlinkWithoutDelay", turn on the LED for a short time (you will have to experiment to obtain best results), and then turn it off again for the remainder of the period.
Keep the on time constant, and subtract that time from the period to determine the off time. As I said you will need to experiment to determine the optimum pulse width, a narrow pulse will freeze motion better without blurring, but will give a lower average/perceived brightness.
You could use a potentiometer connected to an analogue input and use the map() function to select your 10Hz - 70Hz frequency, and then display it on an LCD display, or the serial monitor before converting it to period.