SignaLink "Plug & Play" Jumper Module - SLMOD8RI- This jumper module is compatible with virtually all ICOM radios that use an 8-pin round type Mic jack.
PWR / SPKR Jumper Settings - To maintain compatibility with as many radios as possible, this jumper module has two small jumpers that can be set to enable Power and Speaker Audio.
PWR - This jumper is *NOT* used with the SignaLink USB, but can be installed to power the older SignaLink SL-1 or SL-1+ model from your radio if there is sufficient power available on Pin #2 of the Mic connector (check your radio manual).
SPKR - This jumper should only be installed if your radio has Speaker Audio on Pin #8 of the Mic jack (check your radio manual). If Speaker Audio isn't available, then you'll need to connect an audio cable between the radio and the SignaLink as described in the SignaLink Installation Manual.