50Khz-2GHz Malahit DSP Malachite SDR Receiver Part 2

It seems that I was wrong about the power issue with this device.

It's quite simply a case of misleading wording used by a Chinese seller. The device simply doesn't have a battery hidden in it. This version also doesn't have a decent manual talking about the circuit board anywhere.

What I have worked out though is that a 3.7v lithium polymer battery should do the job. 

I've started printing a case for it - one that should fit the battery and a narrow (sub 8mm thick) speaker. I've sourced both a speaker and a battery (about $40 all up), so I'll be able to fit those when they arrive. 

The case should be important - despite all the shielding around the antenna this version of the board (which seems to be a Hola SDR with the Malachite firmware), touching it can cause some noticeable changes to its reception. I'm also quite weary of having the exposed rear circuit floating around on my desk given that my desk is frequently home to all manner of metal tools, metal pens and every other kind of conductive clutter you could imagine. 

View of the case top in Ultimaker Cura - design from https://www.thingiverse.com/thing:4873531

 I do have a printing backlog; I had the printer out of action for a couple of weeks awaiting some new parts after the OEM Bowden tube started getting clogged after having used PETG and no amount of cleaning seemed to make it reliable. 

Waiting to print is a holder for my Ryobi One+ battery - I'm sick of it taking up space on the workbench when charging (charge sits over the top of it), so I want it up on the wall out the way. I've also got some handles for my tiger oscar's aquarium covers. He can be a little cranky and likes to jump, so we've covered his tank with 8mm acrylic lids - I'm too scared to use glass with him. I could see him slamming into it and breaking it. The problem with the acrylic is that it does bow after a few days (I never anticipated this from acrylic that thick). I tend to flip the lids every so often so they flatten out. 

My solution to the handle problem was to make a base that allowed essentially a block to slide into it and act as a handle. I'd make 2 bases to every handle and glue them on opposite sides of the lids so when I flip them, I can remove the handle and easily put it on the other side. 

I didn't want to have complete handles on both sides - its a lot more work and the height of them would have the underside sitting close to the water. I could just see Kevin the tiger oscar slamming into it, hurting himself and probably destroying the handles. Besides, this method made me up my design game - I had to start thinking about how I'd get pieces to fit together snug when the tolerances are less than 1 millimetre. It's fairly basic compared to what many do, but it does require more thought and design than merely making a plastic cube and using glue. 

TinkerCAD design of the handle and base mounts - one extra in this image due to the original print only having a single base mount.