CG PCB missing resistor. Can anyone tell me the value ?

[dogeatdog]

Hi guys,

Been given a controller to repair after a botched mod attempt. Think I got it all cleaned up, but there seems to be a resistor missing.

Does anyone know the value of it, or can measure it for me ? I would, but I only have Matrix controllers here right now.

It's the red boxed resistor

 

[dogeatdog]

Short story : sync button won't work anymore. I checked it for shorts (none found) and for continuity (registers all the way to the alt points when pressed), so apart from this resistor I'm kinda lost on what to check more.
I've tried 1k, since a few other resistors on the board had that value, but that doesn't help (sync still not working).

 

[modded matt]

it measures 81.1 ohms on my multimeter.

 

[odingalt]

Matt did you go through the trouble of removing it for a reading

Dog to get an accurate reading one would have to remove the resistor from their controller (could be difficult to do without damaging the resistor without the right equipment) but you're probably on the right track just trying random resistors at scales of ten, try 10, 100, 1k, 10k, etc.

 

[dogeatdog]

Thanks, 1k is way over it. Have a kit full of them, so will start from 80ohm and then go up. Have two wires soldered to where the original resistor was, so it's easy to test. Thanks both !

 

[dogeatdog]

Hmm.. tried 80-90-100-1k-2k-10k. No joy. Controller turns on, but when I press the sync button the 4 leds start to blink a bit faster, but not going through the usual cycle.

Hmm (I hmm a lot) : just noticed when trying to mimic the behaviour on a working (Matrix) controller. If I keep another button pressed, then press the sync button, it also does the quicker blinking of all 4 leds. When I release the other button and push the sync button then, it goes through the normal cycle.

So that leads me to assume that one of the other buttons is constantly 'pressed', I was looking at the wrong place all this time. Will leave the 100ohm in there for now (btw Matt, are you really sure about that 80ohms? Cause I've measured *every* other res on board (emphasis on ON BOARD, did not remove them) and they are all, without exception, 1k) ?

I've checked for continuity from ground (yay, Common Ground PCB) to all of the button connected pins on the IC (courtesy of RDC : http://i50.photobucket.com/albums/f320/RDCXBG/Repair/360CGWirelessBoardBottom.jpg), but none register as being pressed.. and yet, one is probably shorted :/

Any dead giveaways I'm overlooking before I toss this PCB ?

 

[odingalt]

This is easy for me to say since I have a bucket of PCB's: I'd toss the PCB. This is unfamiliar territory to me I'm not of much help. Sorry I did not know how to fix this one.

Are you positive that the little chip that is missing was a resistor or maybe it's something else like a little diode?

 

[dogeatdog]

From the pic by RDC and the value measured and the marking R54 I would suspect it to be a resistor. But then again. This was a controller board someone truly made a mess with that conductive glue crap. I'm going to let it be then. Thanks for thinking along