[sjt99]

It is a nice thought, but the space below the board is only a shade more than 3/16 of an inch--about 1/16 too little for our purposes. I still have to do some tinkering to see what I can fit into the board--and I have to be careful not to break compatibility with the boards that preceded it. I may just do a small run of 10 or 20 of these to verify that all of my original assumptions are correct and then proceed to do a modified board that adds the additional functionality we want, assuming I can make everything fit. . .and I can do that, if I abandon the goal of putting the chips in sockets. That gives me a lot more usable real estate. . .

Jim
I haven't hunted down all the potential candidates but some of them can be altered to work, I believe. A few of the designs are made with posts on the bottom that raise it off the board, which could be easily removed.

Here is a surface mounted one.

Model: D1209002
- Color: Brown
- Material: ABS
- Can hold one CR2032 coin cell battery
- Package includes:
- 5 x Coin cell battery holders

Dimensions: 0.98 in x 0.63 in x 0.20 in (2.5 cm x 1.6 cm x 0.5 cm)
Weight: 0.18 oz (5 g)

Steve