The
SimpleStrobe is a Stroboscopic
Tachometer. This is just a fancy phrase saying that it generates
a flashing light whose speed it gives in numbers. Like most such
instruments, the SimpleStrobe is designed to display FPM (Flashes Per
Minute), to correspond with RPM (Revolutions Per Minute) which is the
most popular measure of rotational speed.
Gory Details: Like the LED Panel Driver, the SimpleStrobe uses a PIC as its heart. An external oscillator whose speed is controlled by the knob drives a clock signal into the PIC. The PIC lights up the strobe LEDs for one clock width and keeps them turned off for the other 250 or so. These generate the strobe flashes. The user may cause the PIC to halve or double the rate at which this is done by pressing the "÷2" or "x2" buttons. Another part of the PIC independently counts the time between each LED flash and does some math to determine the flash rate in FPM. This is then shown on the numeric display.
To use the SimpleStrobe, one puts a distinctive mark on the motor or whatever object is being measured (while it's off, of course!). Then the motor is turned on and the SimpleStrobe is pointed at it. The user varies the flash rate as necessary until the mark on the motor is synchronized with the strobe flashes. This causes the mark to appear stationary. The user then reads the numeric display on the SimpleStrobe and sees the RPM of the motor.
The SimpleStrobe is driven by a quartz crystal (like the one that probably drives your wristwatch), so the reading is extremely accurate. The displayed value will always be within 1 RPM of true speed.
This is the prototype version. Soon a production version with five strobe LEDs and a larger knob will be available on the website for less than $50. Look for it!
This device is a "mid-range" level project.
Gory Details: Like the LED Panel Driver, the SimpleStrobe uses a PIC as its heart. An external oscillator whose speed is controlled by the knob drives a clock signal into the PIC. The PIC lights up the strobe LEDs for one clock width and keeps them turned off for the other 250 or so. These generate the strobe flashes. The user may cause the PIC to halve or double the rate at which this is done by pressing the "÷2" or "x2" buttons. Another part of the PIC independently counts the time between each LED flash and does some math to determine the flash rate in FPM. This is then shown on the numeric display.
To use the SimpleStrobe, one puts a distinctive mark on the motor or whatever object is being measured (while it's off, of course!). Then the motor is turned on and the SimpleStrobe is pointed at it. The user varies the flash rate as necessary until the mark on the motor is synchronized with the strobe flashes. This causes the mark to appear stationary. The user then reads the numeric display on the SimpleStrobe and sees the RPM of the motor.
The SimpleStrobe is driven by a quartz crystal (like the one that probably drives your wristwatch), so the reading is extremely accurate. The displayed value will always be within 1 RPM of true speed.
This is the prototype version. Soon a production version with five strobe LEDs and a larger knob will be available on the website for less than $50. Look for it!
This device is a "mid-range" level project.