RJ45 jumper box¶
This is a small circuit board that allows you to prototype arbitrary RJ45 cables / pin-outs. Once the pin-out is confirmed, you can go ahead and crimp a cable with matching pin-out, having verified that it is correct.
laforge finds this very useful, particularly in the context of the many differen RS232 on RJ45 pin-outs in use by various equipment out there.
The PCB design files are available at https://git.osmocom.org/osmo-small-hardware/tree/rj45-jumper-box