Horn Relay Board
£28.20 – £33.00Price range: £28.20 through £33.00 inc VAT
These relay boards are designed to work with our RBT hand throttles. The 3 relay versions can operate twin horns and a single lighting circuit, the 4 relay versions can handle twin lighting circuits. Both versions are available for 12V or 24V systems.
Description
This horn relay board will greatly simplify the wiring of most model locos and enable you to operate twin horns and lighting circuits directly from our RBT hand control box without having to run heavy-duty wires to the handset.
The standard 3 relay version is designed to operate a single lighting circuit. The 4 relay version can be used to allow automatic switching between forward and reverse light circuits. Both versions can be used to operate twin horns of up to 10A. There are versions available for 12 and 24 volt systems [select the one that matches the voltage of your RBT].

A 6 way IDC connector takes two wires from the CLM-807 chassis lead, and screw terminals are provided for the horn, lighting, and power connections.
- The relay contacts can be isolated from the battery in order to operate certain sound cards.
- The board is designed with a number of “break points” that allow for use in many applications.
- It measures approximately 76mm x 60mm.
- The 24v versions can be used with 12v horns / lights by cutting a single track and providing a 12V feed [the diagram for this is in the manual].
- Wiring diagrams for the 4 relay versions are in our knowledgebase
- The full circuit diagram is in the manual
- Note: If being used with car or motorcycle type horns, be sure to fit [the included] catching diodes to prevent damage to the controller.
Manual
The manual is available in PDF format:
The manual is designed to be printed double-sided in A4 booklet format. To print the booklet from the PDF on a double-sided printer, select Booklet in the Page Size & Handling section of the print window, and set Orientation to Portrait.
Videos
We have a couple of videos which explain how to install and configure the HRB
The first gives the basic wiring instructions .

The second is a more advanced explainer on how the HRB works.

