First of all, sorry I haven't posted for so long: I've been working with MAYDAY.US, and working on my Mendel90, so I haven't had much time to work on this.

But I thought I'd let people know that I've worked out *generally* how the units will look and work.

The receiver

The receiver will be a little larger than a Square credit card reader, as I said before.
Here's a picture of a Square reader, if you haven't seen one before:

The credit-card accepting side will be closed, obviously, and the headphones will plug in where the TRRS jack sticks out in the Square reader. If anyone knows of 3d models of Square devices, post them in the comments below.

The "square" in the centre of the top will be a button with a RGB LED behind to signal status.

The transmitter

The transmitter will be fairly large, in fact larger than it needs to be, about the size of a WRT54G router.
The reason for this is that it's going to sit in the TV cabinet, it needs to be large and heavy enough to counteract the torsion of the cables connecting to it.

Very little of the inside space will be used, the front panel, and connector/transmitter PCBs will be separate, with ribbon cable connecting the front to the back.

The lights on the front will be such as power, paired, that sort of thing.

And what's the point of this post?

Because I need to know around what size I'm aiming for to be able to better understand constraints, positioning, etc.