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[Solved] Getting +2.25V on J2 instead of +5V...
Posted: Mar 9th, '17, 08:26
by backdoorranky
I have just finished my build...
I could have sworn I tested the sequencer, but apparently...not?
I'm getting +2.25 V on J2. The voltage is slightly fluctuating under +2.25V. I'm getting proper voltages on J10 on the IO board, and wires are in correct order from 8-1..
I'll turn off the Nava, turn it back on and measure J2 at +2.11V
The sequencer lights turn on differently each time I power up the NAVA.. Sometimes half, sometimes all but one, sometimes just a few...
I can also smell a subtle 'electronics burning type smell'.
I have looked over every solder joint, and touched up each one that looked slightly questionable, even though they all looked fine to me. All ICs are in the right direction..
I'm at a loss at what to do here... I would VERY much appreciate any help!
.....and just now the legs on IC43 just broke off inside the socket...Fuck....Anyone know where to get another Mitsubishi M5218L?
Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 9th, '17, 17:55
by backdoorranky
Would sincerely appreciate any ideas/help.
Kinda heartbreaking spending 40 hours on your first DIY kit to have it not work

Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 9th, '17, 18:09
by KlangGenerator
backdoorranky wrote:Would sincerely appreciate any ideas/help.
Kinda heartbreaking spending 40 hours on your first DIY kit to have it not work

Could you upload some high resulotion shots of the sequencer section (component side)? Are all ICs in the sequencer placed in the right direction?
Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 9th, '17, 18:22
by KlangGenerator
backdoorranky wrote:
.....and just now the legs on IC43 just broke off inside the socket...Fuck....Anyone know where to get another Mitsubishi M5218L?
Try to replace it by soldering a resistor leg to the broken leg. Already fixed one myself like this. If you are in the EU, banzai.com offers genuine M5218l.
Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 9th, '17, 18:31
by backdoorranky
KlangGenerator wrote:backdoorranky wrote:
.....and just now the legs on IC43 just broke off inside the socket...Fuck....Anyone know where to get another Mitsubishi M5218L?
Try to replace it by soldering a resistor leg to the broken leg. Already fixed one myself like this. If you are in the EU, banzai.com offers genuine M5218l.
Actually 7 of the 8 legs broke off..
I'll have to try to find another. Maybe Vincent will sell me one? I am in the US.
I'll upload some photos very shortly!
Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 10th, '17, 02:56
by backdoorranky
Ok, here are a whole bunch of photos that I hope can shed some light/suggestions of what I can do to troubleshoot the problem...
http://imgur.com/a/Aojuq
I've already rechecked all power voltages (other than sequencer of course), and everything looks good there.
I looked over all solder joints dozens of times. Some of the solder joints don't look very good since I went back over them
I'm getting +5V on J10 on the IO board, and +5V on the molex end of the 8 wires as well.
Anyway, I'm at a loss here and I don't know what else to check.
Also in my last photo of the IO board, that IS the correct direction for IC4, right?
Any tips/ideas VERY MUCH APPRECIATED!!
Thank you.
Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 10th, '17, 07:06
by backdoorranky
Also, at the very least, can someone help me get to the schematic? All i get in the download is a .BRD silkscreen, and I can't figure out how to switch to schematic (mode?), only silkscreen without traces.. My beginner guess is that I need to troubleshoot for broken traces/continuity now? I can't think of what else to check for...

Traces starting from J2?
Edit: Looks like i need to check the ICs...will give that a go
Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 10th, '17, 08:31
by KlangGenerator
backdoorranky wrote:
Also in my last photo of the IO board, that IS the correct direction for IC4, right?
Unfortunately not... Wrong direction!

Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 10th, '17, 08:48
by KlangGenerator
Hard to see, but is C29 cap (Low Tom) in the correct direction? Even though it has nothing to do with your problem... From the rest I can't see anything wrong. All ICs are orientated correctly. But I can't see the IC type. Make sure you didn't mess up 595, 165 and 4051. But this also shouldn't be the reason for getting lower voltages... Good luck!

Re: Getting +2.25V on J2 instead of +5V...
Posted: Mar 10th, '17, 21:37
by backdoorranky
KlangGenerator wrote:Hard to see, but is C29 cap (Low Tom) in the correct direction? Even though it has nothing to do with your problem... From the rest I can't see anything wrong. All ICs are orientated correctly. But I can't see the IC type. Make sure you didn't mess up 595, 165 and 4051. But this also shouldn't be the reason for getting lower voltages... Good luck!

Thanks for the input. C29 is seated correctly.
So I've removed ALL ICs in the sequencer, and retested power voltages. Now I'm getting all correct power voltages..
Could an IC not seated in fully/flush perhaps cause improper voltages. I've also flipped IC4 around, thanks for that! Wasn't sure which way was the 'front', since there is no little notch on that one.
Vincent has suggested I install each IC in the sequencer 1 by 1 and test voltages. I will do that now!
Cheers.
EDIT: I think I've found the problem. I've installed one of the IC sockets reversed...probably meaning I installed the IC in the direction of the socket...Rookie mistake..