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Old 5th April 2009, 12:41 PM   #101
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Is your mains ground connected to the chassis?
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Old 5th April 2009, 12:51 PM   #102
JeroenR is offline JeroenR  Netherlands
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Quote:
Originally posted by BrianDonegan
Is your mains ground connected to the chassis?

Not yet. I'm just testing the digital part now and that has no connection to the chassis. That is what made it weird. I was thinking some antenna effect...

I will post a pic later...
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Old 5th April 2009, 01:12 PM   #103
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I think it is static discharge from your hand with no place to go.
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Old 5th April 2009, 01:36 PM   #104
JeroenR is offline JeroenR  Netherlands
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Quote:
Originally posted by JeroenR



I will post a pic later...

Top view...

Left Tent, middle Metronome and COD, right MUX.
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Old 5th April 2009, 01:38 PM   #105
JeroenR is offline JeroenR  Netherlands
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And test rig overview for fun.

I only tested one half of one balanced output. Next is RAKK IV.
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Old 25th April 2009, 11:45 AM   #106
JeroenR is offline JeroenR  Netherlands
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Quote:
Originally posted by BrianDonegan
I think it is static discharge from your hand with no place to go.

The issue is still not solved... When I touch the frame there is a hum/buzz and when I connect the frame to safety ground there is also a loud hum/buzz. Sounds like a 50Hz... I measured the AC voltage between common and frame and it was a whopping 16V!!!

Can it be that because I have mains wire going through holes in the frame that the whole thing becomes in fact a sort of transformer?

Thanks,

Jeroen
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Old 25th April 2009, 04:03 PM   #107
Zoran is offline Zoran  Serbia
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Hi,
I have one Q in general,
but refering to sabre ES9008 output...
Which one of theese two shoud be better at passive IV?
And, what is the lowest value of R iv that I coul apply,
and not to damage dac chip?
Is the lower value of RIV lowering the distorsion for ES9008, same like in
for instance pcm63 and tda1541 dacs?
Or not?
*
I put, just for the test 1K (at each Iout )
the chip remain the just slight warm...
*
thanks
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Old 25th April 2009, 05:50 PM   #108
JeroenR is offline JeroenR  Netherlands
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Quote:
Originally posted by JeroenR



The issue is still not solved... When I touch the frame there is a hum/buzz and when I connect the frame to safety ground there is also a loud hum/buzz. Sounds like a 50Hz... I measured the AC voltage between common and frame and it was a whopping 16V!!!

Can it be that because I have mains wire going through holes in the frame that the whole thing becomes in fact a sort of transformer?

Thanks,

Jeroen
I got some help. The common, safety ground and chassis were not yet connected. After doing this all the hum and buzz was gone, also when touching the frame.

As I did measure a potential difference between frame and common, are there now currents flowing through the frame?

Thanks,

Jeroen
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Old 18th May 2011, 11:45 AM   #109
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Hello Russ

I want to build a dual mono pcm1794 dac and an asrc with src4192.These will be powered up by Salas v1.0 shunt regulators.One 3.3V regulator for asrc and crystal oscillator, one 3.3V regulator for VDD of both pcm1794 and another two regulators, one each for the analogic side of pcm1794

I saw you have implemented in your schematics a filter (clc) on each VDD/VCC for better supply decoupling.
I want to build the coils myself but did not find anywhere what inductance should they have(found only values about impedance at 100Mhz and DC resistance)

Could you please point me to some values?

Thank you
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Old 19th May 2011, 11:22 PM   #110
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Not without doing the same sort of research myself. Honestly when I implemented that feature I had the help of another talented designer who suggested the values.

Cheers!
Russ
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