Andy,
My name is Tim. I'm a new HAM (as of October). Budd Churchward is my father-in-law.
I used this exact diagram for wiring up my Baofeng UV-5X3 and was successfully copying packets for a while. I ended up making the following connections. The wire colors are for my wire, yours may be different.
Base of 3.5mm pin - black wire - PTT
Middle of 3.5mm pin - red wire - AFIN (into the URDC)
Tip of 3.5mm pin - no connection
Base of 2.5mm pin - white wire - GND
Middle of 2.5mm pin - no connection
Tip of 2.5mm pin - blue wire - AFOUT (out of URDC)
I was receiving packets with this setup but now I'm not. Don't know what my problem is other than using the rubber duck antenna.
Hope this helps.
-Tim Fehr
KI7HFW