Trackball PCB replacements needed

[mahuti]

I have an old trackball. Both PCBs seem to be shot. I need to replace them. Anyone know where I can get some that look like the attached file?

 

[lilshawn]

sorry. no idea what those are for. Don't look like standard opto boards though so replacements could be hard to come by.

if you take a look at the optical tx/rx themselves, they should have a number printed on the case. you should be able to buy a couple replacements and fix them right up. The sensors themselves are probably made by Vishay. They aren't a special multi pin logic type or anything.

like an OPB804 or something

[mahuti]

Thanks for the feedback.

Just for interests sake those came from a suzo trackball Ultimarc used to sell back in like 2003 or 2004. Somewhere around then.

[billthecat]

What does the other side look like?  Twisted Quarter sells Wico replacements on eBay.  2 for $10, plus $6 shipping:
http://www.ebay.com/itm/WICO-REPLACEMENT-TRACKBALL-OPTICAL-BOARD-NOS-/360674107927?hash=item53f9da2217:m:mrdtLPmeb9uzdjd1vQw9XnA



Even if they are a different form factor, you might be able to figure out something to hold them in the correct place.  I had a lot of trouble finding any sort of optical board for a Tempest spinner and was able to use these.  Of course, a spinner has more open space than a trackball, so it might not be possible.  But for $16, it' might be worth a try.

If you do, note that the GND and +5V are on the inside pins instead of the outside.

[mahuti]

If you do, note that the GND and +5V are on the inside pins instead of the outside.

Hah hah. Yea. I think that right there is what killed these to begin with. I think at some point the wires got snagged and pulled out. And when I put them back in I had the wires in the wrong spots. Shrug.

Unfortunately the trackball is pretty low profile and those won't fit. I had looked at them too, but I don't think it'll work. Can't get them lined up with the wheels.

Thank you for the suggestions. I don't know if the resistors are blown or the optical units. But I suspect it had something to do with bad wiring.

[BadMouth]

Where you located?  Maybe someone nearby with electronics skills can lend a hand.

Those boards don't look like they contain anything but basic parts that would be easy to test and replace.

[mahuti]

I can solder.  But I don't know what to test on the boards. I have a multimeter somewhere... but I don't know what to check

[lilshawn]

the optical part (the black parts) are made as a set with an infrared transmitter LED and a receiver optical transistor. you would just remove them as a whole and replace them with new ones.

the old ones should have a part number. you can get those as a replacement.

there shouldn't be anything else wrong with the boards.

[mahuti]

Thanks for the advice. I'll take a look today

[BadMouth]

The parts are cheap enough and almost surely the problem. 
Once you figure out a part number, I'd probably just go ahead and order enough to replace them all.
But if you wanted to do some testing:

Hook up 5v and ground to the appropriate pins.
The IR LEDs located on one side of the black modules should stay on all the time.  You can see them through a digital or cell phone camera. (may need to be in a dim room)
Some or all of those being burned out is most likely the problem.

The other side of the black module, opposite the IR LED, is a sensor that acts like an on/off switch and allows power to pass when light hits it.  (through a slot in the wheel)
Ambient light from the room can also trigger it.
Each of the sensor pins  coming off the PCB should show voltage when the sensor is exposed to bright light and not show voltage when it is covered up.
There were some old games that had this backwards, but same principle.  It changes in response to light.

That's all there is to it.  Those two pins just output a blip of power whenever the slot in the wheel passes by.
The sensors are staggered in such a way that allows the computer to tell which direction it is spinning and it can tell the speed by how fast the blips are coming.

(All the terms I used here might not be considered technically correct by people with a deeper knowledge of electronics, but I think they work better for explaining things in layman's terms.  i.e. someone who knows enough to test for power or continuity, but might not know what is meant by terms like "pulled high".  That was me when I first got here.)

[mahuti]

BadMouth, I haven't had time to do what you suggested yet. I will.

That said, does anyone have a good place they like to buy parts from online? These are TCST1000
http://www.digchip.com/datasheets/parts/datasheet/513/TCST-1000-pdf.php

I was searching my regular places and didn't find them. On ebay they're like $8.50 each. If I have to buy all four I'll just get a new trackball

[BadMouth]

It seems the original is discontinued.
To me, the 1103 would be the replacement part.
http://www.digikey.com/products/en?mpart=TCST1103&v=751
The legs are spaced a bit wider (you'd have to bend them), but otherwise the dimensions and specs are what is needed.

I usually order form digikey or mouser.  Digikey's shipping is usually a little cheaper for me, but it might depend on where you live.

I'm nowhere near as experienced with this stuff as lilshawn. 
It would be nice to have his confirmation on this before ordering.   

[ed12]

ya thats them

ed

[lilshawn]

all things being equal, I would go with the 1202. it has an aperture (0.5mm) that closer matches the original (0.6mm)

the 1103 has a 1mm aperture.

in the grand scheme of things I think it won't matter much though.