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Hi
I measured 1.8v DC between +/- on the right bal channel. I was able to adjust it down to 1.14v but then I hit the limit of the variable resistor. Any idea what can be wrong?
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I would start looking for open or shorted solder joints.
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Thanks. I bought my buffalo III with legato second hand in 2011 so I guess it has a Legato 1.02 or 1.03. I have redesigned it recently with a controller etc. and have found some disturbing solutions (the AVCC had output caps where the cap on one side was connected with + to NC and - to out, I guess it should be + to out and - to ground??) Due to this I have two options as I see them 1: Try to fix the legato I have (and search for other possible faults) 2: Order a new legato 3.1 In your opinion. Is the legato 3.1 a soundwise upgrade from the older legatos? One more quick question Do you think thix adc module would be a good match with your retro riaa for at fully digital amp/preamp set-up where one would only want to turn the occasional record. Edited by user Monday, February 23, 2015 5:07:32 PM(UTC)
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I have checked the pcb and no apparent solderbridges. I then reflowed all rigth channel solderrjoints - still the same.
Then I measured the legs of the transiators and all right t channel transiators read lower resistance compared to the left channel
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Just so we can see which version Legato you're using can you post a picture of the board ?
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It is the v3.1. I thought it was 1.03 but when i dismantled everything to reflow the solder today I saw that it was 3.1.
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Quote:legs of the transistors please clarify. Which transistors? And how did you measure? Edited by user Saturday, February 28, 2015 5:49:33 PM(UTC)
| Reason: spelling! ;-)
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QP7-12 and the counterparts on the left side. Measured all transistor legs vs each other using the resistance function on a standard digital multimeter. Edited by user Saturday, February 28, 2015 9:10:11 PM(UTC)
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Since QP7, QP8 and QP9 all are in parallel when measuring those you are to expect the same reading.
Same goes to QP10, QP11 and QP12.
Can you post a picture ?
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I think a lot of the soldering looks less nice. If I were you, I would use a magnifying glass and look for tiny solder bridges. avr300 attached the following image(s):  cut.jpg (52kb) downloaded 11 time(s).You cannot view/download attachments. Try to login or register.
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Here I have marked examples of what I mean. A lot of unwanted either flux and/or solder. Edited by user Wednesday, March 4, 2015 5:19:43 PM(UTC)
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 1 user thanked avr300 for this useful post.
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Yes. I did not solder this myself. I think I will just buy a new one. Thanks for the help.
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