Micro DRO made from tyre tread depth gauge

[BillTodd]

I have looked at some of the schematics and plans for a computer interface for these gauges and part of it is increasing the frequency or something like that so that it reads quicker.

Some of the early types had a fast and slow read speed (usually 100-200mS for improved precision & 30-50mS for easy adjustment ).  For use with my DRO I had to switch them to fast read mode (which is a right royal PITA for a little PIC)

Most of new ones read a little faster at one fixed speed (they don't have the high speed option at all).

Couldn't a person also increase the precision electronically?

Not with the newer ones, they output a BCD signal that is essentially what is displayed on the screen. With the  older 24 bit binary versions it might be possible to filter (average)  the data but it would make the reading speed too slow for use as a DRO

Bill

[kd0afk]

I also noticed that if you turn it off, not only does it remember the last possition it will automatically come on when you move the slide. And if you remove the data port cover reveals the copper traces and what looks like power contacts.

[BillTodd]

I also noticed that if you turn it off, not only does it remember the last possition it will automatically come on when you move the slide. And if you remove the data port cover reveals the copper traces and what looks like power contacts.

They don't actually turn off, they just blank the display (to prevent damage the the LCD with a static display)

Bill

[stirling lad]

just my luck...Santa brought me one of theses gauges...
... and its only 1.5 v.. .......(the black one)...
So is this one going to be to slow then.?


..mike..
alias= lucky ace macwinnin

[BillTodd]

just my luck...Santa brought me one of theses gauges...
... and its only 1.5 v.. .......(the black one)...
So is this one going to be to slow then.?


..mike..
alias= lucky ace macwinnin

Too slow ?

Not necessarily,  the  3v lithium cell should last a bit longer than the alkaline, type but internally they all appear to run at 1.5v.  - Push the thing in and out a few times and ask yourself 'does the display keep up with the movement?' - The two cheap ones I have here seem to be OK.

Bill

[stirling lad]

Bill,
 It does'nt seem too bad ...it does seem slightly different from the others although it appears the same..

it does'nt have the metal spring ive heard folk talk about, ...and the data port?? it does have an extra hole under the rear sticker but it does'nt seem to lead to anything,, or is data port tech talk for an extra hole?
While messing about with it i took the lip/stopper off the end of the ruler piece to see how long it would extend out to if it was'nt restricted, and it read/measured 70mm+ from probe tip to the end of the silver coloured coating on the ruler bit...
but i dont think i would need that extra, but it would'nt take much to make a little extension on the rear to stop it going past its readable/measurable limit...or am i over looking something ?
   
...Mike...