I got my self a Jing JC800 TTL linear scale, trying to hook it up to my DRO Tech Model DRO-3M
The Pin out is wrong and i been looking for days for the pin out or what wire is what and i cant find anything
And the ones i do find the colors don't match what i have
I only have 4 wires, White, Yellow, Red, Black and the shield
I test the wires on the IC and i get
Black = Pin 1 Out 1
Yellow = Pin 2 Out 2
Red = Pin 3 Vcc
White = Pin 12 Gnd
Maybe this scale might not work on my DRO,
Can i connect it to a ethernet smoothstepper or a UC300ETH ???
Without knowing that scale I´d say your wires are as follows:
RED : +5V
BLACK : 0V/GND
YELLOW: Signal (A+ or B+)
WHITE : Signal (B+ or A+)
In order of not burning your scale you can check for continuity from the RED wire to the +V terminal on the LM339. Do the same for the BLACK wire to the GND terminal on the LM339.
One way to test it would be to connect two 330 ohm resistors and leds to the YELLOW & WHITE wires and power the scale with 5V. It is probable that some cell phone charger can be used as the power supply. Confirm first as some only provide about 3.5V.
When you move the slider you should notice the leds turning on and off. Taking 1 for an ON and 0 for and OFF, the sequence should be
0001
0011
0010
0110
0100
1100
1000
1001
Of couse it can start at any position and it may be to fast to notice. Yet if you see the leds turning on and off you can be cartain that your unit works.
Now you will have to check your DRO to find out how to connect your scale.
In case your DRO counts negative when moving the slider forward and does not have the adjustment to correct it just interchange the YELLOW & WHITE cables.
I decided what the hell i will try to plug it to my DRO, so i made sure that i know were the 5 volts and ground was hooked it up and it worked
This is how i connected it
5V ( LM339N Pin 3 ) ( DRO Pin 7 ) Red Wire
0V / GND ( LM339N Pin 12 ) ( DRO Pin 2 ) White Wire
A+ or B+ ( LM339N Pin 1 ) ( DRO Pin 6 ) Black Wire
B+ or A+ ( LM339N Pin 2 ) ( DRO Pin 8 ) Yellow Wire
Shield wire to the outside of the 9 pin connector
Unfortunately standardization has not reached a number of things. Electronic sensors are one.
As an example, there are proximity sensors that use BLUE for V+ and BROWN for GND. Outputs can be RED & BLACK, GREEN & WHITE, etc.
After checking again the LM339 your wire identification seems correct.
Now, it is possible that your DRO requires differential signals as inputs, that is, it may need A+/A- and B+/B-. If that is the case you can add one SN75158P or DS9638 to provide those differential signals. They are functionally identical except for the pin assignment.