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Joined: 5/5/2012(UTC) Posts: 6  Location: Scotland
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Hello
This is very frustrating as this is quite a simple board. It's regarding the version 2.0 LCBPS.
When adjusting the voltage using VR1 and VR2 the adjustment range is very small and outside the value required: on the negative rail its -20.65v to -22.18 and on the positive rail its between 19.77v and 22.45v. I require +/- 15v for legato 3.
I've checked and re-checked everything and all seems to be well including resistor values (variable and fixed). The transformer (2 x 15v 30va) is connected properly for sure. If I leave it on for a while it does seem to heat up very slightly.
It would be great to get some help.
Thank you and best regards.
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Check the diode orientation?
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Rank: Member
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Joined: 5/5/2012(UTC) Posts: 6 Location: Scotland
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hello, yes, checked that, thanks.
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Rank: Member
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Here is an image of the PCB. Note the difference on D1/D2 compared to the image on the TPA site (wich is of a LCDPS). gwikse attached the following image(s):  LCBPS front 001.jpg (190kb) downloaded 45 time(s).You cannot view/download attachments. Try to login or register.
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An image of your build please.
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Rank: Member
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Joined: 5/5/2012(UTC) Posts: 6 Location: Scotland
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Thank you for the replies and apologies for wasting your time - it turned out that I somehow fried the LM Chips - when these were changed it worked perfect... I attached them to the heatsink first and used a very high output soldering iron to solder the heatsinks to the board - doh - this must have been what caused it.
The Buffalo II and Legato 3 really sound good!
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It actually sounds like they were in the wrong positions the first time round...
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