y1 gamma-1 DAC - Page 91

I would just cut the leads with a razor knife, it's a little easier to remove the left over bits then it is to remove the IC in one piece and it reduces the chance of pulling the pads off the board (although it's an expensive part to destroy it's cheaper then a new board).

Your voltages should be OK once the PCM270X is removed but you never know until you get there.

oh,well, i kinda tried to cut them after i desoldered a bunch, but when i was desoldeirng the pads, a couple came off, again im not gonna worry about it cause i was just gonna use the optical input, now i just need to get a case, power cable jack (input w/e you call the plug thats in the device) and a power cable output jack, like for the DC into the device.

thanks for the help

I'm pretty new to DIY, and have been thinking about building a γ1 since I am looking for a DAC. One of the first obstacles is the parts list. First there are several different configurations. Then you need to determine the quantity of each part type to order. It's certainly doable, but I found myself looking for an easier way.

So I put together some javascript to simplify things (DIY even, you might say ). This is basically an exact copy of the one on the AMB site, but with some additional javascript and CSS. It adds these capabilities:

 - a toolbar to hide/show the parts of each configuration A - F

 - tooltips of the actual notes when mousing over the "Note" column on the parts list table

 - summaries of the parts required from Mouser / Digi-Key / Farnell for each config

gamma1 Parts Browser

I may not end up attempting the γ1 as my first project, but hopefully this will be useful to others.

amb & MisterX, I hope this doesn't count as infringement on your work. All the links there go back to the real AMB site. But I'll take it down if this is inappropriate. Actually, you can just use my script on the real site if you want, then there won't be any need for my duplicate page.

Interesting work you've done there. I'm sure it'd help simplify BOM building.

I think the y1 turned out to be a fine first project for me. A good iron is definitely a good send, but you don't really need a Metcal. Unless you're a complete idiot, it's not too hard to figure out how to put what where, and after a few tries, your soldering looks better. Just watch the tutorials on Youtube. The only part that failed for me is the PCM2707. Still can't get it to work; there's continuity from the data pins, but I think the chip is dead. I get nothing from it.

Pro tip: The corner holes take 6-32 screws. I didn't know that (I'm sure it's on AMB's site somewhere), and ended up getting 8-32 by accident. 

Okay so i got my Powersupply working nicely (outputs the correct amount etc) but when i test the points on the board some are wrong, also the switch is red and kind of flickering, the DAC board test points are all fine and dandy but the USB board is kind of messed up, the 3.3 is at like 4.5ish and the 5V closest to the edge is 4.5 as well, but the 5V in the center is just fine,

can you guys help me?

Quote:

Originally Posted by phishhead92 

Okay so i got my Powersupply working nicely (outputs the correct amount etc) but when i test the points on the board some are wrong, also the switch is red and kind of flickering, the DAC board test points are all fine and dandy but the USB board is kind of messed up, the 3.3 is at like 4.5ish and the 5V closest to the edge is 4.5 as well, but the 5V in the center is just fine,

 

can you guys help me?

Try reflowing the solder joints at U3U.  If the voltage at VBUS is too low, it might be a problem with your computer's USB port not up-to-snuff.  Using a short USB cable might help because a long cable could drop the voltage significantly.

Quote:

Originally Posted by amb 

 

Try reflowing the solder joints at U3U.  If the voltage at VBUS is too low, it might be a problem with your computer's USB port not up-to-snuff.  Using a short USB cable might help because a long cable could drop the voltage significantly.

im using a sigma 25 for power, and it outputs like it should, i omitted u3u

Quote:

Originally Posted by phishhead92 

im using a sigma 25 for power, and it outputs like it should, i omitted u3u

U3U is still required if you use external power.  Also, the 5V testpoint labeled VBUS is from USB (if you have it plugged into your computer's USB port) regardless of your power source.

EDIT: The only exception to this is if you don't plan to use USB as a digital source at all (i.e., config E).  But since you're checking voltages of the USB portion I assume you do want USB functionality.

Quote:

Originally Posted by amb 

U3U is still required if you use external power.  Also, the 5V testpoint labeled VBUS is from USB (if you have it plugged into your computer's USB port) regardless of your power source.

 

EDIT: The only exception to this is if you don't plan to use USB as a digital source at all (i.e., config E).  But since you're checking voltages of the USB portion I assume you do want USB functionality.

im only checking the USB portion for the SPDIF out (if i ever need it) but mainly i just want optical in and RCA out, i know its all on the DAC board. but i just want the option, also my other problem is, i was trying to move the U3U at one point and i pulled to hard and some pads came off, now i have seen some techniques about getting past this but i would like it if i didnt have to. (one method i have seen is scrape away until its just the copper and then use a wire or something to connect)

but yes you are right, i do not plan to use the USB for a source or for power

Quote:

Originally Posted by phishhead92 

im only checking the USB portion for the SPDIF out (if i ever need it) but mainly i just want optical in and RCA out, i know its all on the DAC board. but i just want the option, also my other problem is, i was trying to move the U3U at one point and i pulled to hard and some pads came off, now i have seen some techniques about getting past this but i would like it if i didnt have to. (one method i have seen is scrape away until its just the copper and then use a wire or something to connect)

 

but yes you are right, i do not plan to use the USB for a source or for power

bump for help, i still cant figure it out
 

You can use the solder to build a "new" track. It should be fine.

And aren't you essentially building Config E? I'm sorry, I didn't quite understand your question.

Quote:

Originally Posted by K3cT 

You can use the solder to build a "new" track. It should be fine.

 

And aren't you essentially building Config E? I'm sorry, I didn't quite understand your question.

yeah basically, it started out as the full++ but i jacked up the usb chip pretty badly so i might just do the E config, but when i plug in the power supply the switch is red and the usb boards voltages are all messed up (i posted their values above) does it even matter if the usb voltages work since im not gonna be using the USB part?

but other than that, i cant figure out why the switch is red and flickering, i tried to look at each and every part closely and they all look fine so im not sure whats wrong.

bump again for help, cause no one has really said anything to help me out

phishhead92, what are you using as your S/PDIF source?  You are using optical input, right?  Did you install the correct part for the optical receiver (TORX147PL, which should have a black shutter).  Make sure there are no cold solder joint problems on the fiber optic receiver and the CS8416 digital audio receiver/mux chip.  Do you have a source with coax output to test?  That would help narrow down the problem area.

Make sure you configured your source correctly -- some sources would output AC3, ADAT or other non-PCM, non-audio digital streams which are not supported by the γ1.

Also, did you try more than one optical source or Toslink cable to rule out a source or cable problem?

I am using optical as my source. i did install the correct part, i went through the whole board to make sure nothing looked bad, if there was a suspect joint i reflowed it. the CS8416 chip was probably the best looking smd job i did on this board haha, and yes the other smd chips dont have bridges or cold joints either (im almost 100% positive).

i didnt test it initially but i just tried (brand new toslink cable) i hooked it up to my portable amp via a mini-to-mini cable to no avail, all i heard was silence, my source was my comptuer, i was using foobar to play some FLAC files.

but one thing i dont understand if the switch is lit up red, doesnt that mean there is something wrong?

there is one chip that is looking kind of funky (joints wise) but its the U1D, if i were to omit this and jumper JP2D (pin 1,2) would i have to take off those other parts or could i just leave them populated?

EDIT:after some fidgeting and more cleaning the optical option is green , i think i just dont know how to configure my computer cause i still cant hear anything, but that seems to just be a source problem. ill figure it out