Forum to discuss all matters relating to the MPC1000 and MPC2500 operating systems created by 'JJ' (all versions).
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By K. Rah Tue Apr 25, 2017 8:47 pm
Hey everybody, hopefully someone can help me figure out whats wrong with my 2500.

My F1, F2 and F3 keys are suddenly not working. All three of them crapped out at the same time. I put all new buttons in less than 6 months ago, and have used my 2500 (JJOSXL ver. 3.53) almost daily since then with no problems.

The funny thing is, once in a while they will work randomly, and they respond good as new. the keys are not wiggling around and being dodgy but working just as they should... Then they will go out again just as fast as they came.

It's frustrating because I can't save over my work, i have to make a duplicate of everything i do if i make changes. Also I can't change my timing correction or click settings, or even format a CF card.

I dug out my foot switch but unfortunately I have to use F2 to assign it.... arggg

I've been searching here for a while but don't see any similar questions. Can anybody help me?

Thanks,
-Kel
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By K. Rah Sat Dec 23, 2017 6:05 am
Nobody replied but I'd like to give an update because it's confusing me...

For a while, after the previous post, all the F keys worked, but it has gone back to not working again.

Interestingly though, the problem is always one of two things now

Either only 1-3 work, and then it will switch to only 4-6 working. But it is always one or the other. Any ides?
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By JUKE 179r Sat Dec 23, 2017 12:57 pm
Where did you buy the tact switches from? The cheap ones that you buy in bulk on eBay from are usually cheap quality.
Try Omron or Alps 6x6x5 tact switches from Mouser.
You can buy 3 of these Alps 6x6x5 tact switch...
https://www.mouser.com/ProductDetail/ALPS/SKHHAMA010/?qs=%2fha2pyFadugu8I2tvG3Spq0ZWIPwNOK0vHML1LtnMH8=

Or 3 of these Omron 6x6x5 "sealed" tact switches...
https://www.mouser.com/Search/ProductDetail.aspx?R=B3W-1022virtualkey65300000virtualkey653-B3W1022
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By K. Rah Sat Dec 23, 2017 6:06 pm
thanks, it was a new complete board from mpc-stuff, because there were several things i wanted to replace after 8+ years of use. I just find it weird that it always toggle between the same 1-3 4-6 sides. i figured it was an OS problem.
By allank Mon Apr 16, 2018 5:47 am
K. Rah wrote:thanks, it was a new complete board from mpc-stuff, because there were several things i wanted to replace after 8+ years of use. I just find it weird that it always toggle between the same 1-3 4-6 sides. i figured it was an OS problem.


I would send the board back.. hopefully still under warranty from mpc-stuff..
User avatar
By inflict3 Fri Jul 27, 2018 4:48 pm
K. Rah wrote:thanks, it was a new complete board from mpc-stuff, because there were several things i wanted to replace after 8+ years of use. I just find it weird that it always toggle between the same 1-3 4-6 sides. i figured it was an OS problem.


Damn, did u get this fixed?? Sounds like a loose ribbin cable, or like one side of the ribbin cable ain’t all the way in, like something ain’t making contact..
By jaasi Wed Aug 15, 2018 8:42 pm
i just fixed my function board and i have the same problem. f4 - f6 not working, f1 - f3 working fine. It's definitely not an OS problem. It's something with the circuitry.

Does anyone have a suggestion, since it's been 10 years since the las post here?
By jaasi Wed Aug 15, 2018 11:09 pm
jaasi wrote:i just fixed my function board and i have the same problem. f4 - f6 not working, f1 - f3 working fine. It's definitely not an OS problem. It's something with the circuitry.

Does anyone have a suggestion, since it's been 10 years since the las post here?


Well, I just fixed it. Maybe this helps someone:

It was indeed a circuitry problem. I had a look a the board and wrote down a scheme of all the connections. Then I took a capacitance meter (which you absolutely need to solve the problem) and checked if there is current between all the units. And indeed, part of the circuitry wasn't connected properly (between the f5 button and the cable going out of the board). Did some resoldering, and boom! Everything splendid!

This vid gave me the final instructions i needed: https://www.youtube.com/watch?v=cHV25puO-CQ

the problem was that I did a horrible job taking out the contact switches. Damaged some of the circuitry on the board.

Anyways no one will read this probably, but what the heck. 8)
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By inflict3 Thu Aug 16, 2018 12:07 am
Sweet!! Thanks for :worthy: the info!!!
By chaleses Sun Aug 18, 2019 5:39 am
jaasi wrote:
jaasi wrote:i just fixed my function board and i have the same problem. f4 - f6 not working, f1 - f3 working fine. It's definitely not an OS problem. It's something with the circuitry.

Does anyone have a suggestion, since it's been 10 years since the las post here?


Well, I just fixed it. Maybe this helps someone:

It was indeed a circuitry problem. I had a look a the board and wrote down a scheme of all the connections. Then I took a capacitance meter (which you absolutely need to solve the problem) and checked if there is current between all the units. And indeed, part of the circuitry wasn't connected properly (between the f5 button and the cable going out of the board). Did some resoldering, and boom! Everything splendid!

This vid gave me the final instructions i needed: https://www.youtube.com/watch?v=cHV25puO-CQ

the problem was that I did a horrible job taking out the contact switches. Damaged some of the circuitry on the board.

Anyways no one will read this probably, but what the heck. 8)


Hi. im having this problem, f1 f2 and f3 not working since i tried to solder the f2 button, i did the f1 and everything was ok until i did the f2 solder it stopped working. i tried to solder another tact switch but still not working, can u explain how u did the capacitance test? im trying with my multimeter but everything seems to be well connected.
how can i troubleshoot and know if its the function button board and not the main board or the side control board.

thanks in advance
By jaasi Mon Feb 24, 2020 5:25 pm
chaleses wrote:
Hi. im having this problem, f1 f2 and f3 not working since i tried to solder the f2 button, i did the f1 and everything was ok until i did the f2 solder it stopped working. i tried to solder another tact switch but still not working, can u explain how u did the capacitance test? im trying with my multimeter but everything seems to be well connected.
how can i troubleshoot and know if its the function button board and not the main board or the side control board.

thanks in advance


Hi,

sorry for the late reply. This seems exactly like the problem I had. It is for sure a problem in the connectivity within the function button board and has nothing to do with the other components. You probably damaged one of the connections while removing the f2 tact switch.

you need to write down which tact switch (f1 - f6, in your case probably the f2 tact switch) connects to which pin of the cable going out of the board. Then check whether each connection is working by holding the multimeter to a pin at the tact switch and the respective pin at the cable going out of the board. you might have to press the tact switch while doing this, I don't remember.

It may already help to have a look at the board around the f2 tact switch and see if you can spot some damage. some resoldering might solve your problem.

good luck!