[Dan55]

Saturday night DIY bump

 

[amb]

My standard answer for these kinds of issues is to check and reflow your solder joints. In your case I would focus on U1U and U2U, but you should check the others too.

 

[Dan55]

Yes, I guess my SMD (and schematic-reading) skills need some work. Its working nicely now and sounds beautiful. Thanks for the guidance.

 

[R4ABigman]

Hello there again.

My Gamma 1 was sounding amazing, but stopped working a few weeks back (randomly). After pulling everything apart, the symptoms are a short from +5VDC to GND. I don't really know where to start with trying to diagnose this issue.

I've given it a good visual inspection, but cannot see any crossed-joints or foreign objects to cause the short. Is there a good approach to trying to find the problem area, or do I just need to start desoldering everything?

 

[ShinyFalcon]

Separate the halves and see if the short is on the USB or the DAC board. Check U2U, U1D, U5D, U6D for any bridged pins.

 

[fishski13]

with #2 baby due in a few weeks, it's time for me to give up the dedicated hi-fi room. i'm setting up new digs in the office in the basement and figured it would be a good time to go with a computer for source.

my computer desk is on a wall perpendicular to the hi-fi rack. i'm wondering, what length of coaxial cable can the y-1 drive for S/PDIF? i will be using only the USB to S/PDIF board from the computer to my Benchmark DAC1. or would it be better to run a longer length of a USB cable. i need about 12ft. i'm also going to buy a 1T external hard drive.

thanks!

 

[Gilly]

With good quality cable, I can't see 12ft being a problem.

Could you use Coaxial cable, maybe DIY it? I'm going to probibly use CT100 grade (much better than RG69 for TV/ Satellite signals) co-ax, and give it a try.

 

[amb]

12 ft. is not a problem if you use proper 75 ohm cabling.

 

[fishski13]

thanks Gilly and amb!

i've read the y-1 site, but i still have a couple of other questions:
-with USB to S/PDIF only, the y-1 is powered by the computer USB and no external 5V is necessary? will ULED still fire?
-pins 2-3 should be permanently shorted on JP2D?

 

[MisterX]

Quote:

-with USB to S/PDIF only, the y-1 is powered by the computer USB and no external 5V is necessary?

If you wish.

Quote:

will ULED still fire?

Yes.

Quote:

-pins 2-3 should be permanently shorted on JP2D?

If the DAC board is omitted you will not have any power if you do not install a jumper or some other mechanism to connect J2U pin 1 to J2U pin 2.

 

[fishski13]

so, if i don't have a DAC board:
-i can only power from the host USB - if i want to power from an external 5V source, i would need the DAC board with U1D? i do have a regulated 5V wall-wart lying around though. is there anyway i can use this?
-i leave J3U open as this is the umbilical to the DAC board and not necessary for stand-alone USB operation.
-jumper pins 1-2 of J2U together for bus power return.

 

[amb]

Quote:

Originally Posted by fishski13 /img/forum/go_quote.gif so, if i don't have a DAC board: -i can only power from the host USB - if i want to power from an external 5V source, i would need the DAC board with U1D?

The DC power jack is on the DAC board portion... so yes, you need to populate U1D and its surrounding parts: L4D, C1D, R14D-R16D. You also need J4D to allow the power return to the USB board.

Quote:

-i leave J3U open as this is the umbilical to the DAC board and not necessary for stand-alone USB operation.

Correct - you don't need this for only USB-to-S/PDIF conversion, as this is used to carry the S/PDIF or I2S signals to the DAC board.

Quote:

-jumper pins 1-2 of J2U together for bus power return.

No, you should not jumper J2U if you're going to have the DAC board mated to the USB board.

 

[fishski13]

got it. thanks Ti! i hope my computer isn't too noisy via the USB. i would have it up and running tonight but Mouser screwed up my order...again.

 

[Hob Hayward]

*Sigh* more problems...

I had working usb for months, then the light on the toggle stopped coming on when usb was selected (but it would still output sound perfectly fine from all inputs, and light up when spdif and optical were used). I tried to fix that, but nothing seemed to help. I gave up because it was otherwise working fine.

Now for no apparent reason when the DAC is plugged into a computer under windows it comes up with a message saying that the USB device has malfunctioned. I can't imagine whats gone wrong, and I plan to test everything I can when I get some free time tomorrow, but does anyone have any idea why the usb would just stop working? I have a feeling that maybe the mini usb connector was damaged somehow, but I'm not sure.

Thanks! and Merry Christmas all!

 

[amb]

Hob Howard, check all your solder joints (particularly U2D, U8D, U1U and U2U). A marginal joint could "work" fine for some time and then become non-conductive.