RA 0.1" sockets for Cobra expansion

Wondering where to get these connectors? I have a couple of the Cobra expansion boards, but I want to make a couple of my own with shorter connectors. Do you have a manufacturer part number for the ones you use, so I can find a source for them?


One word: Digikey.

You can find any type of headers you want on there if you can bear their terrible WebUI.

Thanks, but that was the first place I looked, along with Mouser and Element14.

They all sell the 3M header sockets with pins on both the entry and back side, but they will not mate properly with the header on the Cobra.

The ones that come with the Cobra expansion are perfect - I was hoping to get the manufacturer & part # for those so I could then find a supplier for units with different numbers of pins.

I’m pretty sure this is it:

(You are talking about the 40 pin SMT connector right?)


Here is the only .1" connector on the BOM:


It’s called out in the design files and BOM that you can download from the Cobra product page.

I’m after the 25 pin female headers in the Cobra expansion board, seen here:



0.1" is the same as 2.45mm they are standard headers. I get they from RS you can get 36 way ones and just chop them down.

Cheers Ian

Just buy a rail and cut them. After cutting use some sanding paper to smooth the cutting side. That’s what I do.

The docs show 21 and 22 female headers. And you say 25 pin. What is right? Just curious.

They’re 25 pin, and yes, you’re supposed to cut them down. But that sucks, as half the time they crack sideways and you break int0 the neighbouring pin and that’s that connector ruined.

You might consider using a heated blade to cut into female headers.

Not gonna crack if it’s melted. :wink:

I stand them on the edge and slide through with a sharp retractable stanley (craft) knife.

I then trim them with side cutters… Never used more than one pin location (have miss counted and left myself short)

Cheers Ian