QuadLN_S Servo Decoder Board
The QuadLN_S LocoNet® Servo Decoder handles servo control, inputs, outputs and LocoNet® communications. Provides complete turnout control of up to 16 compact SG90 servos. Supports stall motors via optional Driver boards. Optional add-on boards for Detection and Signaling. Fully configurable using JMRI. Operates on a conventional LocoNet® with a command station or on a standalone LocoNet® that has no command station. Firmware can be updated using JMRI. Now includes a 3D printed mounting base for easier installation and better support – just gently snug up the 4 included screws (do not overtighten) to mount to your layout in the desired orientation.
QuadLN_S LocoNet Servo Board Features
- Operate turnouts from your control panel, throttle, or JMRI.
- Handles 8 Servos + 8 configurable input/outputs
- Supports up to 16 Servos per board with version 3 firmware.
- Each input/output can be both an external input and a servo position indicator output at the same time.
- Use pushbuttons, toggle switches or external logic from other boards as inputs.
- 2-position (turnout) and 3-position (semaphore, 3-way stub) servo control.
- Local inputs can be locked out via (key)switch or Loconet command. Perfect for continuous running during open houses.
- Turnout Position feedback reporting over Loconet
®to confirm commands are received and acted upon. - Cascade feature allows aligning an entire yard ladder by throwing just one turnout.
- 8 Programmable routes for triggering Turnouts, Sensors and Signals.
- Locally adjust servo parameters using the Remote Align board or set them via JMRI. Remote Align board can also adjust Detector sensitivity and Signal LED brightness.
- Easily configured using JMRI.
- Separate Closed and Thrown speed settings for animation of features like a pile driver – slow going up but fast going down.
- Oscillate mode for easy animation of features like pump heads or wig-wag signal arms.
- Detector Board add-on for 4 channels of current detection with individual sensitivity adjustments.
- Signal Board add-on for 24 LED outputs with realistic effects.
- Field upgradeable firmware (requires Remote Align board and JMRI).
- So much more – see the QuadLN_S manual plus the Signal Board manual and Detector Board manual for all the information.
The latest QuadLN_S Firmware and QuadLN_S Manual are available on the Downloads page.
QuadLN_S Mounting Base
3D Printed Mounting Base for the QuadLN_S. QuadLN_S snaps into the base making it easy to mount vertically or horizontally. Raises the board to allow air circulation without the hassle of dealing with small individual standoffs. QuadLN_S height is unchanged so mounting process for add-on boards is not affected. Just gently snug up your screws when installing – do not overtighten.
Note: these bases are now included with all new QuadLN_S boards.
Installing the Mounting Base

- Insert the QuadLN_S under the clips on the upper edge and lower edge by spreading the edges gently. The two left corners of the board should seat into the left base corners. All the mounting bases edges should now be flush with the top of the board and lay flat against the board edges.
QuadLN_S Decoder Template is Included in JMRI for Roster Entries and Configuration.


QuadLN_S LocoNet Servo Board Is Not Just For Servos!
QuadLN_S LocoNet Servo Board Is Not Just For Turnouts!
QuadLN_S LocoNet Servo Board Is Not Just For Fascia Controllers!
User Support Groups
Tam-Valley-Products@groups.io is the forum for QuadLN_S questions and discussion.
jmriusers@groups.io is the place for all things JMRI.





