I am new to the pi, but an old hand with hardware and software generally.
So I have a pi 3 and a phatDAC (what is the correct capitalization for that anyway? :) ). I presume the installation method is to solder the included header connector to the phatDAC and then just put that onto the GPIO header. Does the header provide enough physical support, or do I need to use the mounting holes at the edge that line up with the holes in the Pi and mount it that way as well?
Also, I see that the 3.5 mm connector ends up above the middle of the pi 3 board. Right now I have the standard pink and white Pi Foundation case. What is the best method to route my speaker cable with this setup? Or do I need a different case?
I use stand offs when possible. Usually one in each of the 4 mounting holes. Two opposite the GPIO header are likely enough in most instances though. Except in your case. Your using a pHat on a full sized Pi. I would just use 2 stand offs in the holes next to the GPIO. It should be enough to stop any wiggle/movement. Or non at all. Putting them in the other two holes may case issues with shorting things out or just not enough room because of components on the Pi being in the way.
The other issue is the Pi foundation case doesn’t make provisions for using mounting screws on the PI. There are nubs that go into the mounting holes of the Pi. So unless you modify the case, your back to using no stand offs.
I had a Pi 3B in that case with a Sense Hat attached. I cut the nubs off with an Exacto knife in the mounting holes opposite the GPIO header. Then put stand offs on the bottom of the Sense Hat. No screws in the end that rests on the Pi. Just to hold it up level. I put the picture frame cover on top to hold it down.
Another option, just throwing it out there, is this case, https://shop.pimoroni.com/products/pibow-audio and one of the two DAC’s shown. I’m one for using what you have on hand, but it doesn’t hurt to have options.
I guess the standoffs are a good idea but I see what you mean about the holes in the Pi – no room for screws. Even if I remove the nubs I would need screws with very thin heads.
Any idea if the pibow case works with the 3.5 mm jack on the phatDAC? It seems to be set up for RCA connectors.
Or drill holes and run screws up from outside under the case? I’ve done that with the Pi Foundation Zero case. My Zero W moved around in the case more than I liked. I drilled two holes using the Pi itself as the template, I ran my drill through the mounting holes in the Pi while it was in the case. Then put two screws with nuts in place to keep the Pi Zero in place. It’s a rover project that might see some bumps etc.
The Pibow case I linked too likely won’t work with your DAC, Both of the cards shown have audio jacks though. Look at the picture and you’ll see a headphone cymbal. That was more of a , if you wanted to start over with a Hat suggestion/option.