urc-9910 B01 buttons not working

Post by **The Robman** » Sun Oct 26, 2014 11:54 am

OK, I found the rest of the files, downloaded them and zipped them together. So try the link again

https://www.hifi-remote.com/forums/dload ... le_id=3221

Ube_Astard · Post by **Ube_Astard** » Mon Oct 27, 2014 2:42 pm

Thanks Robman, really helpful. However, looking at the photos I'm not too sure what to look for as this isn't my forte. Can anyone advise of my keys that aren't working where a broken trace(s) is likely to be? Will it be obvious what it is when I find it?

Thanks

Post by **The Robman** » Mon Oct 27, 2014 8:53 pm

Please give some background to your problem, what makes you think a broken trace is responsible for your buttons not working? Did certain buttons just stop cold turkey or did they gradually deteriorate, requiring harder presses to make them work? If it's the latter case, it's probably the button membrane itself, or possibly dirt and grime on the PCB.

If they went out cold turkey then it could be a trace, is there more than one button not working, if so, which ones? Traces don't just break, you would have had to drop the remote and broken the PCB or done something similar to cause one to break. If a trace does break, it usually takes out more than one button. So identifying which buttons would give a clue as to which trace.

Ube_Astard · Post by **Ube_Astard** » Tue Oct 28, 2014 4:46 am

Thanks Rob, I did mention in the post where I asked for the FFCs but the up/down/left/right, select and exit buttons have suddenly stopped working and even though I have opened up and cleaned the contacts it makes no difference.

Post by **The Robman** » Tue Oct 28, 2014 4:15 pm

I suspect your GUIDE and PREV CH buttons are also broken.

The trick here is to convert the button codes to Octal, to do that, you need to subtract 1 from from the decimal button code and then convert the code. The 2 digit Octal code tells you the two traces used for the buttons. The 8 buttons in question all have Octal codes in the 60-67 range

Ube_Astard · Post by **Ube_Astard** » Thu Oct 30, 2014 6:05 am

The Robman wrote:I suspect your GUIDE and PREV CH buttons are also broken.

The trick here is to convert the button codes to Octal, to do that, you need to subtract 1 from from the decimal button code and then convert the code. The 2 digit Octal code tells you the two traces used for the buttons. The 8 buttons in question all have Octal codes in the 60-67 range

Thanks for replying. I must say however I havent the foggiest how to do what you suggest. Please can you point me to help?

Thanks

Post by **The Robman** » Thu Oct 30, 2014 6:23 am

Open up your remote and study the traces around the affected buttons to see if you can spot a break anywhere. Then, assuming that you find the break, do you know how to fix it? One method would be to use a conductive pen (I think one was mentioned earlier in this thread), another would be to scrap the trace clean on either side of the break and solder a very small wire across the break, just be careful to make sure that the wire doesn't interfere with the buttons themselves.

Ube_Astard · Post by **Ube_Astard** » Thu Oct 30, 2014 6:35 am

The Robman wrote:Open up your remote and study the traces around the affected buttons to see if you can spot a break anywhere. Then, assuming that you find the break, do you know how to fix it? One method would be to use a conductive pen (I think one was mentioned earlier in this thread), another would be to scrap the trace clean on either side of the break and solder a very small wire across the break, just be careful to make sure that the wire doesn't interfere with the buttons themselves.

Phew! It was the octal code thing that got me. I thought you were telling me how to fix it but now realise you were describing how to find.........

Thanks

Ube_Astard · Post by **Ube_Astard** » Sat Nov 01, 2014 4:49 am

I have had a look but cant see anything untoward so maybe I done know what I am looking for. I have linked some macro pictures if anyone can have a glance please.

http://i62.tinypic.com/205xqib.jpg

http://i57.tinypic.com/23r25nk.jpg

Thanks

Post by **The Robman** » Sat Nov 01, 2014 5:49 pm

Do you have a multimeter? If so, what you need to do is, set it for 1k resistance and then test that there is connectivity between all the points where there should be, like the pad on the left of button S60 and the pad on the bottom of button S62, or the right of S61, etc.

Ube_Astard · Post by **Ube_Astard** » Mon Nov 03, 2014 5:44 pm

Thanks for the reply. I have dug out my digital multimeter which I have never used before by the way and it has 200ohm, 2K, 20K, 200K and 2M so I had a dummy run on a couple of pads with the 2K setting to check I got the gist also.This isn't my forte so a little bit of guidance please. For example, button 65 has a short trace going to the left to a hole, then a longer trace to the right to a hole, then it has trace to button 60 and also 2 holes under 65. Do I need to proceed with the tester on 65 while I touch all these points?
Thanks

Post by **The Robman** » Mon Nov 03, 2014 9:26 pm

Any low resistance will work, so 2k is totally fine. Basically, you want to make sure that there is connectivity between all the places where there should be. The cluster of buttons that have stopped working are all joined in some way. Start with the obvious stuff, so when you see two buttons joined on one side or other, use the multimeter to see if the connectivity still works. So do the easy stuff before you try following it through the punch thru holes.

Ube_Astard · Post by **Ube_Astard** » Tue Nov 04, 2014 3:04 pm

Thanks for you patience Rob. I cant get any connectivity from the 64 pad which is the select button (if that one is supposed to connect to the others in the range). The pad is on its own though with a trace going to a punch hole. I have a conductive pen now so what should I be doing to repair it?
Thanks

Post by **The Robman** » Tue Nov 04, 2014 9:49 pm

This is obviously one of the old "donut ring" versions of the 9910 as they had that funny select button. I'm out of ideas here though, I'm afraid.

Ube_Astard · Post by **Ube_Astard** » Thu Nov 06, 2014 8:09 am

Thanks Rob.
Can anyone at all point me where I might go to for some help?