dreamer Posted February 16, 2016 Report Share Posted February 16, 2016 So I finished the CS surface and notice alot of buttons not responding. Did not do much troubleshooting yet hope to get some feedback first or a good starting point or a point out about the problem. The only thing i checked is the wirering combining the CS with the Base board. Also measured with a multimeter checking continuality. All these wires make a good connection. All buttons and POD meters marked RED are not responding. Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted February 16, 2016 Report Share Posted February 16, 2016 Hola... the problem should be fixable :) First... have you checked for correct type and orientation of the input/output shift registers on the baseboard? Many greets, Peter Quote Link to comment Share on other sites More sharing options...
jojjelito Posted February 16, 2016 Report Share Posted February 16, 2016 Sometimes it's just flux residue and too little solder etc. Did you check this already? If that's OK it's probably some issue with sift registers or some micro-bridge in the solder. Check if there's continuity between those traces and compare with the schematic just to make sure. Quote Link to comment Share on other sites More sharing options...
latigid on Posted February 17, 2016 Report Share Posted February 17, 2016 One thing I recently noticed on mine was that the plated through holes were not conducting properly, which is quite strange for ENIG plating. It seems better with both top and bottom pads soldered, or sufficient solder to go all the way through. Careful to avoid big drips and shorts! Quote Link to comment Share on other sites More sharing options...
dreamer Posted February 17, 2016 Author Report Share Posted February 17, 2016 i checked the orientation and the type of the shift registers. These add up. Allthough i wonder if the HC165 type i use is the correct one. Don't think it matters much but if someone can confirm this Did not check the soldering yet.. Quote Link to comment Share on other sites More sharing options...
dreamer Posted February 17, 2016 Author Report Share Posted February 17, 2016 Hmm. soo i just tried the following.. I still had a CS board laying around from the previous time and i thought lets connect this one to the new base board and see what happens. I got exactly the same non responding knobs and buttons as i have with the new CS board.. That shifts my suspect to the Base board. And also this problem looks alot like the problem i had previous time. Meaning that maybe there are some components on the base board that are not working well. So the only thing i re used from the previous time are the ICS. Shift registers and PIC processors.. So is it maybe possible that a PIC processor is bad?? Quote Link to comment Share on other sites More sharing options...
arumblack Posted February 17, 2016 Report Share Posted February 17, 2016 I doubt the PIC or no buttons would work, the input to the pic is just a serial datastream from shift registers, so if some work all should work regarding the PIC. So I'd check shift registers, are the non working buttons all on the same chip? or all at the end of the chain? answering these questions will point towards the fault. Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted February 18, 2016 Report Share Posted February 18, 2016 The 74HCT vs the 74HC provides TTL-level input capabilities - i did a quick datasheet comparison and cannot see dramatic differences... they both are fine operating at around 4.75-5.25V, the TTL version is slightly slower (in the nanosecond range) and that's it... if everything else fails, swap for the HC version, but I don't believe it is the problem... To be precise and to learn a bit: CMOS input levels: 0V to VDD/2 is seen as low, VDD/2 to VDD is seen as high TTL: 0V to 0.8V is seen as low, 2V to VCC is seen as high This should match up nicely in the MBSID. If you have some other shift registers lying around, or even with the same shift registers, you could swap them cyclically and see if other regions of the CS fail. This is a good test to see, if a particular shift register IC has failed (which does not happen very often). This test and following the traces just as arumblack said should lead you to the problem. Most likely, as jojjelito and latigid on said, probably some bad soldering on the baseboard around the shift register(s) controlling the failed CS regions is the reason... Many greets and good luck! Peter Quote Link to comment Share on other sites More sharing options...
dreamer Posted February 19, 2016 Author Report Share Posted February 19, 2016 so i did some swapping around with the hc165 shift registers. And there is definitly something wrong with these. Every time i remove one and place back different parts of the CS board fail. I even had some new ones laying around that never have been used from the same batch and still fails are happening.. I guess a smart thing to do now is to order some ordinary regular ones.. Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted February 19, 2016 Report Share Posted February 19, 2016 Sounds good. Please report back, so we know, if these TTL-level shift registers are unusable! Many greets! Peter Quote Link to comment Share on other sites More sharing options...
latigid on Posted February 19, 2016 Report Share Posted February 19, 2016 Maybe something to consider: with the sink driver transistors the "off" voltage will be raised approximately 1 PN (diode) junction above 0V/ground. Perhaps then if the supply is noisy (?) the TTL low threshold is crossed unintentionally. So I'd expect better results with HC parts. Quote Link to comment Share on other sites More sharing options...
dreamer Posted February 24, 2016 Author Report Share Posted February 24, 2016 WHOOHOO IT WORKS I swapped out the 165'ers with ordinary ones. And i can confirm it works without issues. I also tried my old CS board. And this one also works. I'm kinda annoyed that i didn't try this before cause my old 2011 BASE board is now damaged because of all the troubleshooting i did on this issue. But i have a working MB6582 now 1 Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted February 24, 2016 Report Share Posted February 24, 2016 Cheers! Sounds like a happy end! And we have learned something, thanks for reporting back! :) Many greets, Peter Quote Link to comment Share on other sites More sharing options...
dreamer Posted April 9, 2016 Author Report Share Posted April 9, 2016 (edited) Got meself a new issue i think i just noticed it today. When i connect a audio jack to the MB6582 the synth powers on without using the power switch..??? I can also not switch it off anymore after that..it only powers off when the audio jack is removed again. Don't think it supposed to do that. The same thing happen when i connect the OUT midi port. Edited April 9, 2016 by dreamer Quote Link to comment Share on other sites More sharing options...
Hawkeye Posted April 11, 2016 Report Share Posted April 11, 2016 Hm, that sounds indeed very strange. You'll probably have to open her up again, and examine the section around the power-in plug and power switch. It sounds like some (quite big) soldering problem there... You can also take photos and post them here (frontside and backside, high-res), if you want people to look at it. Good luck and many greets! Peter Quote Link to comment Share on other sites More sharing options...
dreamer Posted April 12, 2016 Author Report Share Posted April 12, 2016 I will create a new topic with details about the problem and high res pictures. Quote Link to comment Share on other sites More sharing options...
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