What Mesa card can translate sinwaves in TTL?

Hi!
I have old liner optical encoder. Its output is sinwave +-10Volt.
Mesa 5i20 accept TTL input signal level.
The question:
Which Mesa card can input sinwaves encoder signal and output TTL encoder signal for 5i20 or similar card?
The optoisolation not needing.

Normally this require a interpolater
(we have a interpolater coming out , the 3I23, but its not available yet)

also are you sure the scale has +-10V outputs?
(+-1V and +-11 uA are common)

If you just want to square the sine/cosine outputs (and lose resolution)
you feed the sine/cosine signals into a differential encoder input with a
say 1K series resistor

I will measure the encoder signal tomorrow and let you know.
The encoder signal comes from CCM and I can not lost any resolution.
In this case I need interpolator, from analog to square signal.

heidenhain makes interpolaters.
IBV are for 1vp, such as:
www.ebay.com/itm/Heidenhain-Sine-Encoder...&hash=item3a8fa8ccf0

or EXE for 11uA:
www.ebay.com/itm/Heidenhain-EXE-602-E-D8...&hash=item51b403c147

These are available with many different interpolating multiples.
5x in typical IIRC.

There are other makes as well.

Chris M

I tested the signal on osciloscope.
3 mV. This is signal stright from the encoder. Sinwaves.

aike wrote:

I tested the signal on osciloscope.
3 mV. This is signal stright from the encoder. Sinwaves.

You have to move the encoder from max to min and subtract to determine
the peak to peak signal value. if it is a current output encoder, then
you have to load it with a known resistance to determine the P-P
current value.

While you are set up to do this, you can also determine the native
resolution of the encoder. Determine how far it is between peaks
on one of the signals, and divide by 4 to get the quadrature resolution.
Or, crank it a known distance, like 1 mm, and count the peaks.
Multiply by 4 to get the quadrature counts/mm. This would be the
NATIVE resolution of the encoder grating, interpolation would
mutliply that value.

Jon

Jon

Dear Jon!
It is analog signal and I measured the loaded curcis amplitude. (600 or 1 KOm).
According to resolution, I will count the number of picks.
But I need to interpolate the analog to digital TTL.
All counting and processing will be done with digital signal, not from analog.
The best way analog input 3mV -> Black box -> TTL 5V.
That is all.

aike wrote:

Dear Jon!

But I need to interpolate the analog to digital TTL.

Interpolation refers to the increase of linear reasolution by subdividing the
native resolution of the scale. That has nothing to do with the conversion
of analog to digital, although it obviously is only possible with analog output
from the scale. Well, since you say this is for a CMM, then interpolation
is most likely needed. Just check with the maker of the interpolator box
to make sure it is compatible with your specific scale model.

Jon

That with the 3i23 sounds interesting. I have a 5 axis mill, I want to upgrade with Mesa. The machine uses 11µA optical
Encoders with I think 20µm resolution. Because the old control want TTL input as well, it have 5 Exes but with your interpolator I think I can reach a higher resolution.