ezDAC v.1.5 Builders Thread

[6h5c]

Good news! Progress!

Ray

[merlin2069er]

Lol, not really.

I put together everything and didn't hear a thing.

I checked the ezdual again, and now it's outputting ~2v/~-15v.

I wonder if something on the ezdac (voltage) input would cause problems on my ezdual?

[paulb]

So the ezDual is outputting that when it's connected to the ezDac but is okay when not connected? I still think you have a short somewhere, but it could be on the output side of one of the positive regulators.
You could depopulate all the (+) regulators on the ezDac and check resistance to ground on both the power input and all regulator outputs.

[merlin2069er]

My ezdual now is outputting ~ +2v/-15v without anything connected to it.

It had been working when I repaired the shorted cap. When I attached it to my ezdac I got nothing out of it, and then rechecked it again (disconnecting it from the ezdac) and got the above voltage.

I didn't keep it plugged in long ... fearing I'd blow another cap or smoke the resistors.

[paulb]

OK. Start by checking the resistance of the ezdac to ground, and then the resistance of each +ve regulator output to ground. Look for a dead short.
Meanwhile, on the ezdual, you can check the voltage input and output on the +ve regulator.
When you're ready to hook them back up, a current-limited lab power supply would be handy if you have access to one. Otherwise, use (say) 100-ohm resistors in the +ve and -ve lines running from the ezdual to ezdac. And connect/disconnect it quickly. You've had your share of smoke and broken stuff on this.

[merlin2069er]

hmm, no wonder i'm getting about 2v on the output.

I've got 3vac at ac1 & ac2 (at the ezdual inputs). I've got 16vac from both taps of the transformer (disconnected from the ezdual).

[paulb]

Originally Posted by paulb

I've gone back and forth on this (I2S vs SPDIF) a few times now. My last post here said I was switching to I2S, but I haven't done anything further on the PCB design yet.

For any that are interested, I'm going back to SPDIF because it's less intrusive to the ezdac and gives more flexibility for other uses.
The adapter board will have USB and SPDIF input connectors, selected by a small relay and associated control signal. I'll start a separate thread once I'm ready to solicit comments on the design.

[PJN]

Hi All,

I'm starting to order parts for my DAC board. On the BOM posted for the 1.5 EZDAC on Evan's site C1,2,4,5,7,8,10 & 12 are shown as 10 uF, however when I go to the digitkey number shown on the BOM they are shown as 100 uF, on the digitkey site. Could anyone please let me know the right value ?

Thanks,

PJN

[TICUL38]

Originally Posted by paulb

For any that are interested, I'm going back to SPDIF because it's less intrusive to the ezdac and gives more flexibility for other uses.
The adapter board will have USB and SPDIF input connectors, selected by a small relay and associated control signal. I'll start a separate thread once I'm ready to solicit comments on the design.

Will be tracking your posts. I have placed this project on the back burner; had to commit to other issues; speakers and woodworking are other hobbies.

Louis

[paulb]

Originally Posted by TICUL38

Will be tracking your posts. ...
Louis

Gosh...
I'll tidy up the schematic and post it here. I haven't done much on the layout yet.