Photo interrupter

I have 2 photo interrupters in this circuit, one for the tuning and one for the steps of the synchronous motor, can someone tell where is the emitter and receiver ?

Please check the picture here :

https://drive.google.com/open?id=0B4hGEKcQurgOdUhOaTA3dEJTSVk

Many thanks

hello guys,

I have 2 photo interrupters in this circuit, one for the tuning and one for the steps of the synchronous motor, can someone tell where is the emitter and receiver ?

Please check the picture here :

thanks for your help

Never seen anything like that. I have no idea what that is. Do you have a vendor link or part number ?

raschemmel: Never seen anything like that. I have no idea what that is. Do you have a vendor link or part number ?

No i don't have a reference , it's similar the this one : http://www.epictinker.com/Slotted-Opto-Switch-Opto-Interrupter-p/it-optoswitch.htm

Use LINKS button to convert it to a working link so I can view ut on my cell phone.

If you can power on the circuit, you can spot the emitter with phone/tablet camera.

Ciao, Ale.

Find a part number and look it up. If that doesn't work then you'll have to reverse engineer the board.

Looks like same parts used in computer mouse.

My best guess is: IR emitter are the clear ones ( some yellow reflection ), and the dark ones are the receiver. For the emitter, to test it, use a DM in diode mode, it should have similar readings as a diode, or LED.

Do the black units have 3 legs or 2?

Power it up and view it using a digital camera ... the infrared emitter will be visible.

The emitter will have a low value resistor connected to it. Leo..

@mehdidib, do not cross-post. Threads merged.

Hi,
the OPs pic.
48e90a09-f985-4d07-a811-aa7910a8b025 (1).jpg

Tom… :slight_smile:

Hi,

one for the tuning and one for the steps of the synchronous motor

What is the PCB out of, can you post a shot what is a bit wider so we can see where the traces go, in particular to resistors. What do you mean by tuning? The opto pairs do not look as if they are in line with each other, do they share the same slotted wheel?

Thanks.. Tom... :)

Take another photo further away so we can read all the resistor values.

Based on the ONE resistor value visable (10 k ohm) connected to the yellow thingy, that has to be the receiver because the emitter would have a value consistent with a led current limiting resistor whereas 10 k ohm is consistent with a photo transistor collector pullup resistor.

CONCLUSION: YELLOW THINGY IS RECEIVER, BLACK THINGY IS EMITTER

I think you're right raschemmel. I can just see a 1k5 resistor connected to the black thinghy on the right.

@ TomGeorge. They line up if they are side-firing. Leo..

Photo detectors with a daylight blocking filter will sense around 830 nm to 950 nm in order to match with the IR emitter's wavelength. This makes the photo detector look black to the human eye, but it's transparent to infrared.

Hi , I am so sorry for the delay , i live in algeria (GMT+1) and i just saw your feedbacks, thanks a lot guys, and sorry again !

my goal is to reverse engineer a PCB motor controller of a Split flap display , the split flap works with a synchronous 48 AC motor.

this is what found in this PCB :

FQP50N06 Transistor MOSFET

MOC3020 : 6 Pin DIP Ramdom-Phase Optoisolators Triac Driver Output

4 x MC3302 : Quad voltage comparator

1 x MC1413B : Hight Volatge, Hight Current Darling Transistor Arrays

3x MC14516B : Binary Up/Down Counter

MC14081b : Dual 4-Input AND Gate

2 Photointerrupters ( I have 2 photo interrupters in this circuit, one for the tuning and one for the steps of the synchronous motor )

After 3 days of work i made an initial Control Schematic :

I want to use the original 16-conductor multi-drop ribbon cable ( check the top of PCB please), i want to know what i get from every conductor of the 16 conductors and control the motor using an arduino.

like the example here :

https://www.youtube.com/watch?v=ISs-sn-Swj8

What should i do next ?

Many thanks for your help !

thanks guys, the black is the emitter