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Joined: 5/17/2010(UTC)
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Location: Norway
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I might have been a little careless and killed my bipolar placid, at least it's not working.
When powering it up, usually, all lights except D6 lights up. And output voltages will be 22-23v (15v transf.)
I can't seem to adjust voltages either.
One or two times I managed to get D6 lighting up when startup, but gradually faded to nothing. When troubleshooting, the first thing I noticed was wrong, was R13 had a bad joint (started to cook when on for a while). Then I noticed VR4 was bad, changed that one too.
This is the most significant things I've done/discovered.
Any suggestions most welcome.
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Rank: Administration
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Check to be sure you have not reversed the two large transistors QN1&3 / QP1&3
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Rank: Member
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They seem to be right. J5200 on the QN's
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Rank: Member
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Joined: 5/17/2010(UTC)
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Location: Norway
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GOD D*** #@&£$¤"#&%
I've used OPA277 instead of 227!! Now, how the **** am I going to desolder those.
Any tips on that please?
Do you gurus think there are other complications as a consequence?
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Rank: Administration
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While the OPA277 is far from ideal for this cct, it should cause no harm.'
My guess is that a short somewhere probably killed one or more transistors.
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