Basic Board Help

[jamesmcuk]

Hi

I need a bit of help with this board. This board is one of two that work similarly. One which is working detect a printer cart being inserted when a bit of dark plastic goes between two sensors. The second pictured works the same way but detects if ink is in the cartridge through a window in it. Anyway. Its not working but I don't really know how to bypass it.

One the back of the board represented by the colours on the pic are the sensors each colour is the pair for each cart. I could do with help trying to understand how to solder this up to make the board think the sensor can not see the other i.e. there i ink in the tank.

Also what would NT1 be?

Thanks in advance

James

[stj]

Re: Basic Board Help

no idea on NT1, mer the resistance on the working one.

as for the rest, they are pairs of an led and sensor.
to see which is which - look at them with a camera.
or show the other side of the board.

what printer is it, brother?

[budm]

Re: Basic Board Help

What is the P/N of those OptoInterupter?
http://www.utopiamechanicus.com/arti...ptical-switch/

[jamesmcuk]

Re: Basic Board Help

Hi Guys, Thanks very much for getting back to me.

When I use a camera to look at them they do not light up as would be expected. I am going to go get my VM now and see whats supplied to the led circuit and yes its a brother.

OptoInterupter! Thats what I should have searched for would have saved me a lot of time lol! Thanks. As for P/N - it says N73 on the bottom and 2x2 o the side. attached is a pic of the top side.

Will measure now and update.

Thanks again guys for your interest.

[budm]

Re: Basic Board Help

Can you show the pictures of what are printed on the body of those Opto?

[jamesmcuk]

Re: Basic Board Help

This a few views of the board

Thanks

[jamesmcuk]

Re: Basic Board Help

OK Bit of an update. The working cart inserted board seems to have 1.18v at the LED side of the sensors and just over 3v on the receiver side. The resistance of the receiver goes from around 2k when covered to 900ohms uncovered. Does this sound right?

The none working board has the 1.18v on the led side but does not seem to have a voltage on the receiver. I am not sure though if this is due to one being snapped off on the end of the receiver circuit. I can't see that is the case though as they appear to be wired in parallel.

With no volts the receivers are open circuit.

[stj]

Re: Basic Board Help

what model is that? i'v never seen inside a modern brother, interesting to see the cartridge area, and where the waste goes etc.

[jamesmcuk]

Re: Basic Board Help

its a mfc-j65100w

[budm]

Re: Basic Board Help

OK based on this picture:
https://www.badcaps.net/forum/attach...0&d=1461868467
That part to the right of the board is the LED for the P11 Photointerupter, and the two holes with 'E', and 'C' marking are for the Phototransistor.
So look at the other sensor and look for E, C markings on the board.

[budm]

Re: Basic Board Help

BTW, when you check the DCV between Pin E and pin C without anything between the slot, the DCV should be <1V, and when the slot is blocked by solid material, the DCV should go lots higher than 1VDC.

[jamesmcuk]

Re: Basic Board Help

OK done a few measures but get nothing on the damaged board across the phototrans. The working board however does as you say and ramps up when blocked.

This is the best I can work out for the layout of the board attached. I can see the 1.18 v supplying the LEDs but cant see any v on the phototrans. That said if I put one lead on the phototrans and the other on pin 3 or 4 of the ribbon I can see it go above 2.5v.

[jamesmcuk]

Re: Basic Board Help

On another note the missing part was there and it wasn't detecting the black cart. Now its snapped off its the same error. Do you think I just need to jumper 3v to pin 2 on the ribbon?

[budm]

Re: Basic Board Help

So you put the bad board in the good working machine and the Voltages do not look right compared to the good working board?
The Photo transistor is turned off when you have blocker between the slot so the DCV between E-C will be high. So the one that showing 0V between E and C when blocked means that the transistor is bad and not being turned off.

[jamesmcuk]

Re: Basic Board Help

The machine has 2 boards doing the same thing. One set monitor the carts being inserted which is working. Once inserted the second board is used to see if there is ink in the cart. This is the one that appears to be broke as the printer acknowledges the cart but then says can't detect which from what I have read is what happens when this board goes faulty.

So there is only one machine and I am trying to figure out how to override or fix the ink monitoring board to get it to print again. If I could just remove this board I would but it doesn't like that either LOL. Ultimately I just want to trick the printer into seeing full ink carts. The broken board straddles the cartridges and the beam is broken by a window. I guess if there is ink in the window it breaks the beam.

[jamesmcuk]

Re: Basic Board Help

another forum showed this http://www.techsupportforum.com/foru...ml#post2423149

its a different cable and printer but interestingly its pin 5 they cut. Do you think that would work here for me.

[budm]

Re: Basic Board Help

To simulate that the Photo Transistor is turned OFF (Blocked) you will need to remove the E leg or the C leg off the board so the transistor will no longer be in the circuit.

[jamesmcuk]

Re: Basic Board Help

looks like the problem may be somewhere else then as the black cart PT is not even on the baord any more lol and it still says cannot detect black cart.

[stj]

Re: Basic Board Help

i thought it detected what cartridge was in each slot by reading the eeprom on the top?

[fzabkar]

Re: Basic Board Help

I can't understand how you can measure 0V between the E and C pads in the black circuit if the transistor is not present, unless there is a problem on the main logic board.