This board provides connectors to extend the MRCS power and phone bus (used by the EBF31A Battery Feed and ATSN Dispatcher/Operator Boards) to as many as 12 stations. Pads are provided for a bucking converter to develop 12VDC for buzzers, LEDs and Relay Latches.

Version 2.1 has pads for a 5A schottky diode to handle higher current loads than the smaller one used previously. This is overkill, but a friend gave me a life time supply. Pads for the SD103A-TR are still provided.

I’ve been developing a series of circuit boards to perform the various functions needed to build a layout phone system, but I never made a central board to distribute the phone line and auxiliary power. In the past I assumed the user would use either telephone style “66 blocks” or barrier strips to distribute these signals, but that has become a road block for some users, so this board, with its on board screw terminals, puts the basic connections in one place.

Features:

• Takes power from the 6-conductor modular telephone and +24V power bus (note to phone people: this is positive 24 to keep things simple for non-phone model railroaders)
• Two 6 conductor Jacks are provided for daisy chaining the bus. Connectors are oriented with the locking tab up for easy connection and disconnection.
• Connector pads provide up to 12 connections on 0.100 centers for Tip, Ring, +12 and Ground. (If you are assembling your own board and need less connections, you can use terminals with fewer positions)
• Optional auxiliary 6 position screw terminal brings all lines on the bus out for easy access
• Polarity protection diode protects against use of non-reversing (DCC Bus 6 conductor cable)
• Pads for LM2596 bucking converter: provides 12V for buzzers, LEDs and Relay Latches etc.

Technical documentation including EAGLE CAD files and Instructions can be found on my GitHub Page