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So, I mis-wired a project to my LCBPS, and had a "magic smoke" failure of the third degree (D1 exploded right off the board! O.O ). I've replaced D1 (double-checked polarity) and also the LM317 regulator, but the maximum I can coax out of the positive side is only +8.7-ish volts. What else could I have killed? Edited by moderator Wednesday, March 1, 2017 9:03:04 PM(UTC)
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Probably replace D3 and check capacitors for shorts. What voltage to you measure across C3's pins? Edited by user Thursday, February 16, 2017 2:10:54 AM(UTC)
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Originally Posted by: Brian Donegan  Probably replace D3 and check capacitors for shorts. What voltage to you measure across C3's pins? Replaced D3, same result. Voltage across C3 is approx. 28 Volts--so was the voltage across C4. The confusing thing is C3, C4, C5, and C6 also appeared to test as open. I pulled C3 and verified it. I dunno, maybe my multimeter is registering too fast to check or is otherwise faulty. 
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Capacitors will generally test as open with a continuity meter (depending on the meter). You should use a capacitance meter if possible. What is the AC input voltage? 28V would suggest something close to 20VAC. Is it possible you damaged the through-hole plating when desoldering? Edited by user Sunday, February 26, 2017 5:50:04 PM(UTC)
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 1 user thanked Brian Donegan for this useful post.
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Originally Posted by: Brian Donegan Capacitors will generally test as open with a continuity meter (depending on the meter). You should use a capacitance meter if possible. Yeah, my MultiMeter is pretty cheap, maybe time for an upgrade. ;) Quote:What is the AC input voltage? 28V would suggest something close to 20VAC. I'm using an 18V-0-18V Transformer, it's inputting about 21.5V AC Quote:Is it possible you damaged the through-hole plating when desoldering? You nailed it...I messed up the via on the LM317 pin two--the top pad was open to the pin. Soldering the top pad to the pin fixed it. Muchas Gracias! :)
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