Variable frequency delay

[Nikyu]

I have a strobe light which is used to view rotating machinery. It
uses a magnetic tach sensor which has a 0 - 5V output. The output
goes directly into the strobe. I would like to be able to rotate the
image captured by the strobe. Basically, I want to delay the 0 - 5V
signal from the tach by something on the order of 1 ms. The big
problem is the frequency of the rotating equipment is not constant, it
can range from 0 to 2500 rpm. So depending on the angular speed, a 1
ms delay would cause a different angular shift in the image I see.

What I want is about a 15 degree rotation of the captured image and
slow and high speeds.

Any ideas?

Thanks!

Eric

 

[Jasen Betts]

I have a strobe light which is used to view rotating machinery. It
uses a magnetic tach sensor which has a 0 - 5V output. The output
goes directly into the strobe. I would like to be able to rotate the
image captured by the strobe. Basically, I want to delay the 0 - 5V
signal from the tach by something on the order of 1 ms. The big
problem is the frequency of the rotating equipment is not constant, it
can range from 0 to 2500 rpm. So depending on the angular speed, a 1
ms delay would cause a different angular shift in the image I see.

What I want is about a 15 degree rotation of the captured image and
slow and high speeds.

Any ideas?

get 23 more sensors and a 24 way switch?

possibly something could be done with a microcontroller
something with a timer with PWM and event capture and a few lines of
code.

there's an analogue solution too

in ramp peak |\
---generator-+-detector---rheostat---| \
| comparator -- edge --- out
`-----------------------| / detector
|/

 

[Nobody]

I have a strobe light which is used to view rotating machinery. It
uses a magnetic tach sensor which has a 0 - 5V output. The output
goes directly into the strobe. I would like to be able to rotate the
image captured by the strobe. Basically, I want to delay the 0 - 5V
signal from the tach by something on the order of 1 ms. The big
problem is the frequency of the rotating equipment is not constant, it
can range from 0 to 2500 rpm. So depending on the angular speed, a 1
ms delay would cause a different angular shift in the image I see.

What I want is about a 15 degree rotation of the captured image and
slow and high speeds.

Any ideas?

Use a microcontroller. I can't think of a solution using discretes which
isn't significantly more complex.

The obvious discrete solution is a phase-locked loop (PLL) with a 12-stage
twisted ring counter as the divider. That gives you 24 signals at the same
frequency as the input, with phase shifts in 15-degree steps.

A much simpler solution is an absolute delay which can be varied via a
knob. You manually adjust the knob until you're looking at the right part.
This assumes that the speed doesn't vary while you're looking at it.

 

[whit3rd]

I have a strobe light which is used to view rotating machinery.  It
uses a magnetic tach sensor which has a 0 - 5V output.  The output
goes directly into the strobe.  I would like to be able to rotate the
image captured by the strobe.

So, use a phase-locked loop (CD4046 type) with one or
two decoded counters (CD4017 type) in the reference
branch. That will give you ten to twenty taps at
various phases with respect to the input.

 

[neon]

when it comes to time lm555 is the answer just use as a monostable oscillator [oneshot] for whatever delay you want with a potentiometer setup the delay can be from 2ms to minutes even hours.the info is all over the internet about lm555