[tomb]

One trick that works for me sometimes is to use an X-acto knife to "slice" between the pins.  That can get some of those bridges that might be underneath and hard to see.  For lack of a better description, think of it as using a comb to clear anything between the pins.  Also, try to be cautious about removing/replacing many more things before you get a handle on it.  These boards are fairly robust with the double ground plane, but they're still protos and may not take much abuse.

 
EDIT: Just thought of one other thing - you may need to be patient with the connection to the PC.  Mine took awhile to register for some reason, but I've had no trouble with it since.
 
Anyway, don't give up and good luck.

 

[forsakenrider]

Yeah ive tried the xacto comb. I dont know. I re flowed U2 and U4 and used desolder braid and flux to suck as much away as possible. Tomorrow I work so I will put a litt Acetone around the chips and blow it with the compressor. Acetone is ok isnt it? as for the boards and their strength, yeah Ive already lifted one pad at U7 but i should be able to make it work anyway. First step is to try and figure out with the 3.3 reg over heats with L3 installed. If I measure the RIGHT pad of L3 to ground without L3 installed I now get 0.6 ohms so I think I've only made the short worse tonight
 

 

[cobaltmute]

If that compound you are using is actually conductive, you could have an issue with U4 - look at the board and you'll see three ground plane vias right under the chip - one of which is close to 3.3V pins.
 
Yup right pin of L3 to ground should no be 0.6 Ohms - you've definitely got a ground short.
 
And as tomb mentioned - these are protos.  It can be rather easy to lift a pad.

 

[forsakenrider]

Heres a quote from the site, do you think this could be my problem?:
 
"Not Electrically Conductive:
Arctic Silver 5 was formulated to conduct heat, not electricity.
(While much safer than electrically conductive silver and copper greases, Arctic Silver 5 should be kept away from electrical traces, pins, and leads. While it is not electrically conductive, the compound is very slightly capacitive and could potentially cause problems if it bridges two close-proximity electrical paths.)"

 

[cobaltmute]

Based on that quote, I'd say you should be good.
 
So now it is time to hunt the bridge.

 

[forsakenrider]

I brought it to work and blew it out with the air compressor. no solution. I'm starting to get frustrated with this little guy!!!
 
I really cant figure out where the short is. Could it be the actual dac chip?

 

[cobaltmute]

How high of magnification are you using to look at it?
 
I use an 8x loupe (something like this: http://www.amazon.com/dp/B000RB3FPE/ref=asc_df_B000RB3FPE1485372?smid=AG275D7O3JJ72&tag=dealtmp9995-20&linkCode=asn&creative=395105&creativeASIN=B000RB3FPE ) that I bought for $8 at a local shop.  It shows more than clear enough so you can check each and every pin.

 

[forsakenrider]

Probably not high enough! Im frustrated so I will have to find me a loupe like that! thanks for the idea.
 

 

[particleman14]

k mines up and running.  all voltages check out and I'm getting about 2.5mv offset on L and -6.5mv on R.
 
I managed to compare a few songs to my gamma-2 (fed to CKK3)... So far,  the Pup1 sounds pretty good... while I'm listening to some pink floyd and fleetwood mac  First thing that sticks out is gamma-2 seems to have more "depth"  than the Pup1 which sounded kind of "thin" in comparison.  However, both sounded great in the classic rock department(def leppard, foreigner). 
 
Comparing various electronic/pop music, the Pup1 does a good job.  But, I think the I am liking the bass on this thing the most, it's nice and fat with just as much clarity as the y-2.  To my ears, the overall presentation of the y-2 is better, but I am also reminded it's about 4x the cost as this Pup1. 
 
I wonder if finding a way to use a THS4222 would change the sound dramatically?  Anyways, I am pleased with this little guy (esp. for the price)., I'll compare it to the grub later this week if I can. 
 

 

[cobaltmute]

Quote:

Probably not high enough! Im frustrated so I will have to find me a loupe like that! thanks for the idea.
 

This just brings up a very good point:  I'd say you need magnification to build SMT.  You need some to build the PCB (I use a ring light with a magnifier in the middle), but lots of magnification is important to check the board.
 
Personally for any part with three or more legs, it comes out of the vise and gets checked thoroughly before I move onto the next part.  I've still missed bridges, but I was always ultimately able to find them with good magnification.
 

 

[cobaltmute]

Quote:

k mines up and running.  all voltages check out and I'm getting about 2.5mv offset on L and -6.5mv on R.
 
I managed to compare a few songs to my gamma-2 (fed to CKK3)... So far,  the Pup1 sounds pretty good... while I'm listening to some pink floyd and fleetwood mac  First thing that sticks out is gamma-2 seems to have more "depth"  than the Pup1 which sounded kind of "thin" in comparison.  However, both sounded great in the classic rock department(def leppard, foreigner). 
 
Comparing various electronic/pop music, the Pup1 does a good job.  But, I think the I am liking the bass on this thing the most, it's nice and fat with just as much clarity as the y-2.  To my ears, the overall presentation of the y-2 is better, but I am also reminded it's about 4x the cost as this Pup1. 
 
I wonder if finding a way to use a THS4222 would change the sound dramatically?  Anyways, I am pleased with this little guy (esp. for the price)., I'll compare it to the grub later this week if I can. 
 

Nice to hear about a successful build.  With the dc servo on the CK2III, you should have no worries about the offset from the pup1.
 
On the next version of the board, better layout around the op-amp should increase the choice of op-amps.
 

 

[forsakenrider]

I used a similar light as you to build it, and I still feel and I can see really deep. To me it looks perfect, but theres obviously something I'm missing.
 
Other then the short for the 3.3 reg, what could be causing my 2.5 not to work? In goes 4.85-4.9v and out comes 4.2. I fried atleast one of them carelessly shorting too pins, and maybe even the other so I will have to order extras when I order parts for the Skeleton.
What could be causing this? or rather, where should I look for something wrong?
 
Jeeze, this is getting embarrassing! I've never had a problem assembling something from plans
 

 

[cobaltmute]

It seems like something is bridging across the output of the 2.5V reg.
 
So if you remove L5, what are you getting on the 2.5V point?
 
You can always try running unregulated rails for the op-amp, but I'd want to make sure there is nothing else wrong.
 
 
 
 

 

[forsakenrider]

FINALLY! we have progress. so it wasn't a solder bridge on one of the DAC chips! it is somewhere before or L5. removing L5 and the dac is recognized by my computer. I will have a little something to eat and see what we can get! I just hope my two 2.5v regs arent burnt out!

 

[forsakenrider]

ok, I THINK everything is solved. its like there was a bridge under L5 or C31. I didnt see anything but removing and reattaching both all is well, except the 2.5+ because I burnt both my 2.5 regs! (well I assume they are burt since I saw a little magic smoke and they both put out exactly what they take in). So what can I do now? I will order new reg's but is there something I can do in the meantime? will the opamp take the +5~v if I bridge pins 1 and 5? Will I need to do the same on the Negative side? or is there a way to connect the negative 2.5v reg (I have one extra) to the positive (funky pin change?).
 
One other thing, sometime it shows up as "Unrecognized USB device", not sure why and I cant repeat it, it seems random. Other wise it shows up as "USB Audio Dac".