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Nothing on the DAC side of things. :)
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OK, pics at last...and some notes * Preliminary layout until I fit everything in (HiFace USB to replace dddac.de USB-I2S and Tent Clock modules) powered by its own bridge and 15kuf Jensen 4 pole capacitor - unregulated (and probably should be) * Extra rectifier bridge not used - a carryover from the last project * Lundahl 1527XL transformers - wired in parallel each side to reduce op impedance (not that relevant to this issue) * Placid installed today (old version) - set to around 327mA and 5.5V * Note - despite the switch on the PSU (Brian suggested I add to ensure the firmware/Vol and Buff 2 were synced) and the Placid supply the Volumite still doesn't work properly * Automute LED is now not on and lock is - which is normal. (Flash makes it look like Automute is lit but it is not) Buff 2 Pics - initial implementationDid this help troubleshoot things? Cheers. Edited by user Monday, February 21, 2011 4:47:16 AM(UTC)
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Haven't you wired the positive supply line (usually red) to the GND pad in stead of VCC on Volumite? Cheers, Nic EDIT. No - it seems wired the same (red = GND) on Buffalo. Edited by user Monday, February 21, 2011 10:27:39 AM(UTC)
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kpavey - do you have access to an oscilloscope ?
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Hi AVR
Yes I have an old ex Saudi Airforce Tektronics 475 CRO. A couple of broken knobs but she works OK. What did you have in mind?
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I once had similar problem. It turned out that it was a faulty (programmed) Atmel.
Try to measure the digital lines. SCL will continuously send a clock signal. SDA will continuously send the digital representation of the pot position. In other words, both lines will be "live" all the time.
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Rank: Member
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Thanks for the tips AVR Is the clock signal the same as BCLK? I guess it's unlikely to need to be anywhere near that fast. Followup - can only measure what I'd describe as noise - 50-200mV max, period around 1us, generally sinusoidal but nothing constant and repeatable like you'd expect a clock to be. Similar rubbish on both SDA and SCL. Then.... I was swapping in my valve preamplifier late tonight, and went to try the Volumite on the odd chance it would work. And now it does. I did NOT change anything in the DAC at all, I left it on whilst changing out front end preamplifiers. Very odd. Hopefully it stays this way. Hmmmm. The pot is not that linear in its response, seems like a 30dg turn from full on takes out 85% of the volume. I assume that's normal? Edited by user Tuesday, February 22, 2011 5:17:39 AM(UTC)
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It's normal. It's not implemented linear, but logarithmic.
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Rank: Member
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But.the pot IS linear right?
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So it say in the BOM.
"5K Linear"
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