A3 LED does not light up and terminal 4 and 5 at 0V [resolved]

Alfy · 1627

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Offline Alfy

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Hi everyone,

I finished putting my kit together and went through the tests. Alas, the A3 LED did not lit, and the number 4 and 5 terminals showed 0V. Terminal 9 also showed 66V, which is quite a bit lower than what the manual indicates.

So I went through the build again, first checking those particular terminals and those directly linked to them, then going through every single terminal. Although I resoldered a couple of terminals, I cannot find any fault. Would anyone know what particulars I should check according to my tests results?

Thanks in advance!

Alfy
« Last Edit: January 04, 2018, 04:00:21 AM by Caucasian Blackplate »



Offline Paul Birkeland

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Reply #1 on: December 23, 2017, 07:16:49 AM
Terminal 4 is wired to terminal 2.  If you have 0V at terminal 4 and something else at terminal 2, then they are not wired together.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Alfy

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Reply #2 on: December 23, 2017, 09:16:06 AM
Huh, I do get normal readings for terminal 2. I’m not home for the Christmas holidays, but I guess I’ll have to check the little wire between 2 and 4 next week. Thanks!!



Offline JulianBaynes

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Reply #3 on: December 23, 2017, 02:20:42 PM
I just posted this exact same problem before I saw this post. I found that the wire connecting terminal IB on the small board to terminal 4U had broken off. I would check that.



Offline Alfy

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Reply #4 on: December 27, 2017, 01:45:31 AM
Well, I checked the little wire between 2 and 4, it looked fine. The solders looked fine, I gave it a tug and it was fine. I tested it with my MM, and it wasn’t fine.  ::)

I then had a bit of an issue with sound coming out only from one side. After rechecking he resistances, I found an issue in B3, but a bit of a wiggle put that to rest. It does make me wonder how well I made my built, though...

Anyways, thanks for the help everyone, I know have a working Crack, which is pretty amazing for a first project!



Offline Paul Birkeland

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Reply #5 on: December 31, 2017, 10:15:41 AM
Be sure not to listen to your Crack until it passes the voltage check.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Alfy

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Reply #6 on: January 03, 2018, 06:12:39 AM
I did go through the full résistances and voltage tests again before listening (I’m among those who got really scared by all the warnings!  ;))

I do have an additional problem, and I hope someone will see it here so I don’t have to make a new thread:

I now brought my crack back with me, and after taking the plane, I only get sound in the left channel. As before, wiggling B3 puts that to rest. I should have resoldered immediately, for I have no tools with me now.

Before I give it to an electronic shop to resolder that terminal, would someone know if a bad connection between B3 and terminal 5 would cause the loss of the right channel? I understand it could also be something else, but everything else checked before I took the plane, so that wire is the most likely culprit.

Thanks in advance!



Offline Paul Birkeland

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Reply #7 on: January 03, 2018, 07:02:48 AM
Yes, it sounds like there is still an issue with a solder joint. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Alfy

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Reply #8 on: January 04, 2018, 02:56:54 AM
Yep, resoldering B3 did the trick, I now have a working Crack (and darn, does it sound nice from the get go despite my newbie mistakes!). Again, thanks for taking the time to help out.