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avr300		#21 Posted : Sunday, January 17, 2016 2:25:55 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		If we are dealing with a bad via, try reheating this spot. cut170116-4.jpg (16kb) downloaded 23 time(s). And while you have the PCB pulled from the enclosure, take a good sharp (not to much flash) picture of the bottom side and post it.
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tiguan		#22 Posted : Sunday, January 17, 2016 2:51:07 PM(UTC)
Rank: Member Groups: Member Joined: 11/16/2015(UTC) Posts: 21 Location: İstanbul		Originally Posted by: avr300 If you do have -2,49 at C8, Quote: C8B - ... -2.49 IC2 3 ... - 0.99 then you also need to have -2,49 at the pad where pin3 is supposed to make contact - it only one single track on the PCB. cut170116-3.jpg (25kb) downloaded 21 time(s). Get hold of your magnifying glass ;-) We need to get this running so you can listen. Now I recognized in between c8 - leg and opamp 3 leg something is hapening. I just made measurement 4 in a row 1 min in between I always read -2.49 at R13B leg no 1 BUT what I read at C8 - leg and opamp leg 3 changes. 3 times of this try I read at c8 - 0.99 Opamp leg 3 each time different voltage is not stabil. And it dont fix at a figure flactuating while I touch. ???
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avr300		#23 Posted : Sunday, January 17, 2016 3:00:07 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		Then you have to pull the board and have a look underneath to see what's going on in this area. cut170116-5.jpg (16kb) downloaded 26 time(s). Edited by user Sunday, January 17, 2016 3:04:56 PM(UTC)  | Reason: Not specified
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avr300		#24 Posted : Sunday, January 17, 2016 3:02:36 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		When the board is working, no matter what this areas has to be same potential. cut170116-6.jpg (26kb) downloaded 37 time(s).
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tiguan		#25 Posted : Sunday, January 17, 2016 3:10:06 PM(UTC)
Rank: Member Groups: Member Joined: 11/16/2015(UTC) Posts: 21 Location: İstanbul		Originally Posted by: avr300 If we are dealing with a bad via, try reheating this spot. cut170116-4.jpg (16kb) downloaded 23 time(s). And while you have the PCB pulled from the enclosure, take a good sharp (not to much flash) picture of the bottom side and post it.
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avr300		#26 Posted : Sunday, January 17, 2016 3:19:15 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		This is the interesting part. cut170116-8.jpg (31kb) downloaded 44 time(s).
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tiguan		#27 Posted : Sunday, January 17, 2016 3:31:36 PM(UTC)
Rank: Member Groups: Member Joined: 11/16/2015(UTC) Posts: 21 Location: İstanbul		Originally Posted by: avr300 When the board is working, no matter what this areas has to be same potential. cut170116-6.jpg (26kb) downloaded 37 time(s). Here I took some pictures First at negative leg of cap Second at resistor Here the tripod for mobile phone or how you call it :) :) :)
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tiguan		#28 Posted : Sunday, January 17, 2016 4:08:52 PM(UTC)
Rank: Member Groups: Member Joined: 11/16/2015(UTC) Posts: 21 Location: İstanbul		Originally Posted by: avr300 This is the interesting part. cut170116-8.jpg (31kb) downloaded 44 time(s). I renewed all solders here. But still the same.
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avr300		#29 Posted : Sunday, January 17, 2016 5:37:29 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		Place a piece of wire (cut some off a resistor leg) between the two solder points.
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tiguan		#30 Posted : Sunday, January 17, 2016 7:24:58 PM(UTC)
Rank: Member Groups: Member Joined: 11/16/2015(UTC) Posts: 21 Location: İstanbul		Originally Posted by: avr300 Place a piece of wire (cut some off a resistor leg) between the two solder points. And the oscar goes to avr300 Thanks a lot. I read now - 2.22 at both points resistor leg and cap - leg and also opamp 3 rd pin. But it now reaches 14.70 v and fixes. No flactuation at all. I could not imagine that there could be a problem with pcb. Again thank you.
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tiguan		#31 Posted : Sunday, January 17, 2016 7:57:47 PM(UTC)
Rank: Member Groups: Member Joined: 11/16/2015(UTC) Posts: 21 Location: İstanbul		May I ask one last question. What shall be the ideal shunted current.
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avr300		#32 Posted : Sunday, January 17, 2016 8:00:19 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		50 to 100mA depends on your ability to cool the thing. Congrats. I'm glad to have helped you.
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avr300		#33 Posted : Sunday, January 17, 2016 8:02:06 PM(UTC)
Rank: Member Groups: Member Joined: 6/17/2008(UTC) Posts: 921 Thanks: 1 times Was thanked: 70 time(s) in 69 post(s)		Originally Posted by: tiguan May I ask one last question. What shall be the ideal shunted current. Feel free to ask all the questions you want.
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