[Kibble Fat]

amb, MisterX,

I am having trouble getting my Full++'s optical input to read a signal. The LED switch stays red, the toslink fiber is glowing red, and I can see the sound level changing in my laptops control panel. Obviously the first thing to try would be swapping out the DAC and swapping out the source, but since I have nothing else that would work, I'm wondering if you have any troubleshooting pointers?

The laptop is an ASUS running Windows 7 x64. It has a 3.5mm headphone/optical output combo controlled by a Realtek driver. I switch to the digital output using the Sound control panel.

Thanks for any advice!

 

[shrimants]

Hey man, try uninstalling the realtek driver and using microsoft's one off of windows update. You should also remember to set your output driver to SPDIF or whatever windows labels your optical output as. Also, make sure that your player itself is using the correct output.

 

[Kibble Fat]

After a few hours of changing settings, uninstalling/installing various sound drivers, restarting/reconnecting, disabling/enabling, and trying to use AC3Filter, I got it to crackle for a few minutes playing the control panel test sound. The LED switch was switching between red and green very rapidly. Do I have a bad solder joint or IC?

 

[shrimants]

it could still be the computer itself, but if nothing else its a bad solder joint. I dont think bad IC though, or im pretty sure the whole thing wouldnt work.

 

[MisterX]

Does it behave the same way when the USB to optical output is patched into the optical input?  
 

 

[Kibble Fat]

So USB > DAC then run the toslink from output to input? Fiber doesn't light up on any switch settings, so there's no sound. USB sound works perfectly

 

[Kibble Fat]

Here are my boards (again) in case you can spot something that's obviously wrong.

 

[MisterX]

From the Y1 instructions page:
 
 
Quote:

Take care not to mix up the fiber optic receiver and transmitter modules. They look identical except for the shutter color: The TORX147PL is black and the TOTX147PL is grey. The opposite is true for the Sharp modules: The GP1FMV31RK0F has a grey shutter while the GP1FMV31TK0F is black.

 
It appears you did not use the Sharp modules so......
 

 

[Kibble Fat]

The soldering looks pretty good so let's assume reflowing is not going to help.
What are the numbers on the component you have installed in the U2U position?
What's the color code supposed to be for a 22 ohm resistor?
And... check that you don't have the TORX and TOTX modules crossed up.

U2U reads: A08L
My 22 ohm resistor must be mislabeled

TOTX and TORX were switched

:BOWDOWN: Thanks MisterX

y1 DAC board
+3.3V reads 3.291 V
+4.5V reads 4.75 V

Unfortunately, I'm only equipped to test the USB-fed functions at this time. I'll try to get the 22 ohm resistor when I order the enclosure from Newark

from here: http://www.head-fi.org/t/355293/y1-gamma-1-dac/1395#post_6864744

So I've already switched the TOTX and TORX once. I'll have to double check the part numbers when I get home.

 

[Kibble Fat]

Just got back from a meet at Jude's secret hideout and was able to test my Gamma2 input and laptop output (individually).

My Gamma2 performed flawlessly when fed by the optical out of Jude's iPod > Fostex HP-P1. False alarm guys!!!

My laptop graphically showed that the test signal was playing, but there was no sound from thread's MicroDAC > SR71B. I'm actually kind of relieved that my laptop was the problem. While this may be harder to fix or find a fix for, I at least have all of my electronics problems consolidated on one P.O.S. ASUS gaming laptop. Hooray.

 

[shrimants]

Lol you know you're an audiophile/electronics geek when you would rather have your 2000 dollar laptop break than your 200 dollar project.

 

[ericj]

gamma 1 kit finally arrived from glass jar audio the other day and i completed my build yesterday. 
 
Except for two capacitors and a reset manager that i forgot to order from mouser for the gamma 2. 
 
(doh). 

 

[Mullet]

Need some trouble shooting help here.
 
Here's the back story of what happened:
 
I've built a few Gamma-2s and 1 Gamma-1. About a year or so ago I had one channel go on one of my Gamma-2s and took the kitchen sink approach and rebuilt a complete Gamma-2 board. This evening I was playing two amps from the Gamma-2 portion of the DAC (one via RCA jacks and the other via the 1/8" jack) and I was fiddling with the amp (turning up the volume) that was connected to the 1/8" jack and I saw a few sparks because a metal 1/8" connector was touching the pot, which is also metal. This tripped the E12 on my CTH -- the other amp. I proceeded to unplug the first amp (A47) and then after firing up the CTH again noticed a buzz coming out of the left channel and proper audio coming out of the right channel. I tested the Gamma-1 portion and it plays music normally. So I know its the Gamma-2 with the issue. This time I want to avoid rebuilding the whole y2 board. Any ideas on what to check what died or is dying? U7, U5? What voltage readings and what pins should I check?

 

[Mullet]

Upon using a DMM I'm getting these readings... I've decided to do the typical tests when done with a Gamma-2. Everything checks out with these voltages. Then I decided to take a look at the outputs of U7. On a known working Y2 I got these readings going into C20 (R) and C26 (L) -- 2.27v and 2.28v. With the bad Y2 I got 2.202v on C20 and 4.33v on C26. I'm assuming now that there is something wrong with U7 and I'll try and use some chipquik to get the chip out. I tested the points coming out of the U5 and I got similar readings of 2.2 to 2.3 volts for L and R of both sides of the DAC. So I'm thinking the DAC isn't the problem and it's most likely U7 that got severely damaged. Keep in mind -- no magic smoke and the right channel still works. Does this make sense?

 

[jdkJake]

Pics would help,

I would also reflow the main parts and use your DMM to check for shorts between the pins. No reason to remove any chips quite yet. The y2 is very easy to soldier bridge on the SMD parts if you are not careful.