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Offline adam1016

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LED's not glowing
« on: October 24, 2015, 01:29:16 PM »
Alright, fixed that, now the 2 LED's on the A side of the High current regulator board over the D socket aren't glowing.

Offline adam1016

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Re: Re: Resistance Check Fail
« Reply #1 on: October 24, 2015, 01:35:48 PM »
My voltages are all pretty much normal, except on KregA I'm getting 1.9V, and on IB, I'm getting 197V. 

Offline fullheadofnothing

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Re: LED's not glowing
« Reply #2 on: October 24, 2015, 01:45:24 PM »
IB on which board?
Joshua Harris

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Offline adam1016

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Re: LED's not glowing
« Reply #3 on: October 24, 2015, 01:50:29 PM »
Low Current

Offline fullheadofnothing

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Re: LED's not glowing
« Reply #4 on: October 24, 2015, 05:30:24 PM »
OK, so the A side board has non-lighting LEDs, but all voltages are correct (odd...).

Your B side board is lighting, and all voltages are correct, including OA, which is connected to term 16, which is connected to IB on the low current board, where the voltage is incorrect (very odd...).

Your symptom list doesn't make a lot of sense. Which LEDs aren't lighting? What are all of your voltages? Can you post some pictures of your build?
Joshua Harris

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Offline adam1016

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Re: LED's not glowing
« Reply #5 on: October 25, 2015, 06:07:27 AM »
Alright, I'm going to give you all the voltages.  Unfortunately, I can't take pictures at the moment.
Low Current C4S:
IA: 168V
OA: 85V
Kreg A: 1.9V
BregA: 169V
IB: 200V
OB: 83V
KregB: 1.21V
bRegB: 200V


High Current C4S board over socket D:
IA: 203V
OA: 200V
bA: 0V

IB: 0V
OB: 122V
bB: 200V


The other High Current C4S board
IA: 193V
OA: 170V
bA: 0V

IB: 0V
OB: 141V
bB: 192V


I accidentally shorted IB and OB while testing this, and the LED's on the A side of the board briefly went on, then turned off.  Now, the LED's on the A side of both boards are not turning on.
Headphone Jack:
.001 V on both terminals

Online Paul Birkeland

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Re: LED's not glowing
« Reply #6 on: October 25, 2015, 07:00:58 AM »
Can you post photos of your build, with emphasis on the boards (top and bottom).

Did you short IB to OB on the low current board, or one of the high current boards?
Paul "PB" Birkeland

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Offline adam1016

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Re: LED's not glowing
« Reply #7 on: October 25, 2015, 07:02:23 AM »
Alright, I'm about to take pictures.  I shorted it on the high current board, but the transistors don't seem to be blown, as there's no low resistance across their terminals.

Offline adam1016

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Re: LED's not glowing
« Reply #8 on: October 25, 2015, 09:56:22 AM »
http://imgur.com/a/qLfnf  Here are the pictures of my Crack-a-two-a, I made sure to get good photos of the boards.  Thanks!

Offline fullheadofnothing

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Re: LED's not glowing
« Reply #9 on: October 25, 2015, 10:48:37 AM »
Could you add some pictures of the bottom of boards to check soldering and jumpers; it is hard to see if all parts were soldered from the top (i.e. look at the B side 150KΩ, 431s, some others too). Also pictures of boards at other angles to confirm part values of transistors would be helpful.
« Last Edit: October 25, 2015, 11:36:21 AM by fullheadofnothing »
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Offline adam1016

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Re: LED's not glowing
« Reply #10 on: October 25, 2015, 11:24:31 AM »
Alright, it would be a huge pain to take pictures of the transistor values, but I double and triple-checked and everything seems right.  Here is an imgur album of the high current c4s boards, if you need the low current one, just tell me!

Offline fullheadofnothing

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Re: LED's not glowing
« Reply #11 on: October 25, 2015, 11:31:11 AM »
Where is the album? Transistor values would be helpful to give a second set of eyes, jumpers and solder joints even more so.
Joshua Harris

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Offline adam1016

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Re: LED's not glowing
« Reply #12 on: October 25, 2015, 11:34:25 AM »
Sorry, didn't even realize I forgot to post the album  http://imgur.com/a/rLoqS

What are you thinking it might be?
« Last Edit: October 25, 2015, 11:38:36 AM by adam1016 »

Offline fullheadofnothing

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Re: LED's not glowing
« Reply #13 on: October 25, 2015, 11:50:35 AM »
There is definitely some sketchy soldering there. Look at the last picture. Look at the soldering on the 22KΩ resistor. See how it's just kind of a lead sticking out in the middle of the hole. That's not good. You want a nice shiny little cone of solder on every single joint. One of the 2907 joints seems to be completely unsoldered. These are just a few examples. Any bad solder joints on any board or elsewhere should be fixed pronto.
Joshua Harris

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Offline adam1016

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Re: LED's not glowing
« Reply #14 on: October 25, 2015, 11:52:32 AM »
Alright, I'll reflow all the joints on both boards, just to be extra sure that it's not soldering!