The GrubDAC - Page 64

I don't know at what point in the troubleshooting the pictures were taken, but

I looked at them very closely at their original resolution and I didn't find

any "unintended" connections. The connection from C9 (?) to the Wolfson

looks to be on its last legs and my need repair, but otherwise I think the

soldering job should work. The PCM may be fried by earlier mistakes though.

Just my Nickel (Canada doesn't have the penny any more...).

Quote:

Originally Posted by Avro_Arrow 

I don't know at what point in the troubleshooting the pictures were taken, but

I looked at them very closely at their original resolution and I didn't find

any "unintended" connections. The connection from C9 (?) to the Wolfson

looks to be on its last legs and my need repair, but otherwise I think the

soldering job should work. The PCM may be fried by earlier mistakes though.

 

Just my Nickel (Canada doesn't have the penny any more...).

OK - I've been looking at it all this time from my phone and I guess the display left a lot to be desired.  I can see now that I was mixed up (but not about only two bridged pins on the PCB design).  Thanks for correcting me.

I agree if there are no bridges, then the PCM is probably fried.

Quote:

Originally Posted by Avro_Arrow 

I don't know at what point in the troubleshooting the pictures were taken, but

I looked at them very closely at their original resolution and I didn't find

any "unintended" connections. The connection from C9 (?) to the Wolfson

looks to be on its last legs and my need repair, but otherwise I think the

soldering job should work. The PCM may be fried by earlier mistakes though.

 

Just my Nickel (Canada doesn't have the penny any more...).

The connection from the C9 to the Wolfson looks weird in the photo but I believe I reflowed those pins anyways after the photo was taken.  The continuity tests out fine. 

Quote:

Originally Posted by tomb 

OK - I've been looking at it all this time from my phone and I guess the display left a lot to be desired.  I can see now that I was mixed up (but not about only two bridged pins on the PCB design).  Thanks for correcting me.

 

I agree if there are no bridges, then the PCM is probably fried.

Got the PCM2707 in.  Replaced it.  Triple checked for bridges, both visually and continuity testing. Tested the continuity from the pins to the trace points. Everything looked and tested perfect.

After plugging in, I first noticed the LED flickering and then the regulator was getting very hot.  Unplugged.  Traced and checked ALL of the components for shorts...twice. Nothing.

Plugged back in check the voltages. Before I could start measuring, smoke starts coming from the PCM chip. Fried again!!!  

A bunch of the pins are grounded now on the PCM that were definitely not before so definitely fried.  I have another PCM (was intended for a PupDAC build) but I don't trust the board at this point and removing this PCM this time has wrecked the anchor points. 

I refuse to give up and I going to order a new board from Beezer (along with a PupDAC PCB, future project) and I am going to place a reorder for the components at mouser. One problem is that the Crystek Oscillator is no longer stocked at Mouser.  Can someone suggest a alternative or maybe Tom has one he can sell to me and add to my PCB order when I place it?

Quote:

Originally Posted by Caretaker007 

Got the PCM2707 in.  Replaced it.  Triple checked for bridges, both visually and continuity testing. Tested the continuity from the pins to the trace points. Everything looked and tested perfect.

 

After plugging in, I first noticed the LED flickering and then the regulator was getting very hot.  Unplugged.  Traced and checked ALL of the components for shorts...twice. Nothing.

 

Plugged back in check the voltages. Before I could start measuring, smoke starts coming from the PCM chip. Fried again!!!  

 

A bunch of the pins are grounded now on the PCM that were definitely not before so definitely fried.  I have another PCM (was intended for a PupDAC build) but I don't trust the board at this point and removing this PCM this time has wrecked the anchor points. 

 

I refuse to give up and I going to order a new board from Beezer (along with a PupDAC PCB, future project) and I am going to place a reorder for the components at mouser. One problem is that the Crystek Oscillator is no longer stocked at Mouser.  Can someone suggest a alternative or maybe Tom has one he can sell to me and add to my PCB order when I place it?

I am sorry to hear this.

Send me a PM and I'll shoot you a new grubDAC PCB.  If there's any chance it was the PCB, I'd rather just give you another one.  I probably have a crystal, too, although the one we changed to on the pupDAC is OK for the grubDAC, too:

C3391-12.000

Just an FYI, but all the pupDAC PCB's are electrically tested.