How do I install jumpers on this set up

Help!!!

Stuck on this set up. terminals are numbered 1, 2. & 3.

2 cable pairs coming in, 1 pair goes to 1 & 3 the other to 1 & 2.

Where do I stick the jumper lead or will Ring wired even work with this set up!!!

Hi @user23137. You are going to want to find out which of those 1, 2, and 3 terminals indicate trans, front, and back. To help you figure that out, you will want to get the make and model of that pre-existing chime and look up a manual for it online. Also, verify that the transformer supplying power to your pre-existing chime follows these specs: 10-24 VAC, 40VA max, 50/60Hz. Once you have that information, the jumper cable will go on the terminals that indicate trans and front. The terminal that indicates the back will be left alone. If you are not comfortable taking these steps, we strongly recommend consulting a qualified electrician.

You can also use the Plug-In Adapter 2nd Generation, which simply plugs into a wall outlet and is wired to the back of the Doorbell for power. I hope you find this information helpful.