I am testing a Bluetooth audio and setting up an RF chamber setup for the audio device and i have a 3.5mm audio jack output from one of these Bluetooth devices which i need to transfer to another RF box using the ports available behind this RF box, it has USB, banana plugs and RF RCA ports(posting pic), what is my best option here? remember i need to convert both ways to take this connection out of the box and back into another similar box, many thanks in advance for the helpers.
I'd use the banana plugs. Ground is common across the black terminals. Tip (of the TRS) can go to the red connector on the left and Ring (of the trs) can go to the red connector on the right. Sleeve is ground, and thus goes to one or both of the black connectors.