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November 12, 2019, 10:43:49 PM

Author Topic: 1 LED lights up immediately after turning it on, smoke from one of the 270ohm 5w  (Read 894 times)

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Offline Paul Birkeland

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Now remove the wire leaving OA (that goes to the terminal strip) and recheck.
Paul "PB" Birkeland

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Offline Jimb0

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still nothing PB

Offline Paul Birkeland

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Can you post photos of the board?
Paul "PB" Birkeland

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Offline Jimb0

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Sure PB, will post them in a bit

Offline Jimb0

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pics

Offline Jimb0

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btw, one of the rings on the board for the 2n2222 came off on the bottom side but i was able to solder the top side

Also, none of the LED's light up on that board. I remember all of them use to light up when I tested it the first time around before the 270 ohm starting smoking
« Last Edit: August 27, 2019, 06:38:27 PM by Jimb0 »

Offline Deke609

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Jimb0 - Don't know if this will help, but it's worth a shot. From your first pic of the board underside it looks like there are lots of little solder shards around the soldered legs of the transistors - they might be forming a solder bridge and shorting the legs together. Maybe try gently scraping them off.


cheers, Derek
Derek
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Roon Intel NUC ->  Yggdrasil DAC -> BeePre (w/ BeeQuiet and EML 300B)  -> Kaiju (w/ DCFil and EML 300B) or Stereomour II (2A3 [EML Mesh] and 45 Conversion [EML 45B])  -> Audeze LCD4

Offline kgoss

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Check the LED orientation.

Maybe I'm wrong, but from the pictures it appears the LEDs on the B side are in backward according to the silkscreen on the board.
« Last Edit: August 29, 2019, 02:51:54 AM by kgoss »
Ken Goss

Offline Paul Birkeland

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I would recommend contacting replacement parts and asking for a new board, transistors, resistors, and heatsinks/mounting kits.  Once the traces start to lift off, getting the board to work can be more challenging. 
Paul "PB" Birkeland

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Offline Jimb0

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Will do, thanks PB