[sdiy] Round pin 0.1" headers

[Neil Johnson]

Hi Tom,

> Does anyone know of a source of round pin 0.1" headers suitable for making daughter boards?

There are many ;)

> The usual square pin ones are great, and fine on a breadboard, but the pins are slightly too large to fit into an IC socket,
> so they're not so good for this application.

The big variable you have to content with is the target DIP socket.
There are many types, some are much better at taking things other than
actual DIP packages than others.

> I'd like something that would allow me to pull a 40-pin DIP uP out of its socket
> and stick a replacement daughter board in instead.

When I made and sold M110 emulators for the JEN SX1000 I sold it
together with a spare 40-pin turned-pin/machined DIP socket for
customers to replace the mega-cheap socket originally fittted, thus
ensuring a robust connection.

Then the easiest way to mount the board is with something like these:
http://www.digikey.co.uk/product-detail/en/220-1-40-006/1175-1527-5-ND/3441522

I found I had to stack a couple of sockets between the plug-in module
and the PCB to allow clearance for the existing components.
So the stack looks something like:

PCB - daughteboard
through-header
socket
socket
PCB - motherboard

The turned-pin pins and sockets mate very securely so once assembled
you need a decent screwdriver and gentle nudge from a hammer to
separate them.

Cheers,
Neil
--
http://www.njohnson.co.uk