Pins 1 through 4 on J1 are used to select the operating mode; pins 4 through 7 are used to select the type of signal heads you are using. Pin 8 in used to enable or disable approach lighting. The installation of these plug-on jumpers is shown in figures that accompany each mode diagram and connection list.

The R49 Yellow tint control is provided so you can set get the best possible yellow from your red/green two color LED’s. Typically, this adjustment only needs to be made once. Use a small screwdriver, and turn the control gently clockwise or counter-clockwise until you are satisfied with the yellow color. This control has no effect except when using 2-color LED’s to get a yellow color.

The board activity indicator is a LED that blinks about 2 times per second whenever power is applied to the MSC. If the LED is out completely, the power supply is either not connected, or the 5-volt supply on the board is shorted to ground by a connection to pin T. If it is on, but not flashing, then the processor is not functioning. Turn off the power to the board by unplugging the AC adapter provided for about 5 seconds. Then plug it back in. If the LED still does not blink, the board may not be working. Please contact us for help in troubleshooting or to arrange for a repair.

If you have a lot of MSC’s in your layout, you may find it more convenient, when installing and wiring them, to mount the in a group so that all of the connector pins are readily visible and easy to reach. One way to do this is to prepare a pair of aluminum angles, ½” x ½” by whatever length you need to mount the group of MSC’s. Figure 5‑ 2 shows one way to mount a group of our boards. Our MSC, BD8, GCC and GCX boards all use the same connector, and can be mounted as shown. The end holes in the angles are used to mount the angles to bench legs or some other type of support frame. When mounted this way, the PC boards should be in a vertical plane to allow for better cooling. Note that, because of a heat sink, a BD8 mounted in such a group needs a 1.5” spacing on the component side of the board.

A good practice, when mounting boards in this fashion, is to use as many different colors of wire as possible, with standard colors assigned for similar purposes. For example, try using red for the red LED’s, green for green LED’s, yellow for yellow LED’s, black for SIGCOM connections, white for +5 volts, blue for tumble down west wires, gray for tumble down east wires, tan for turnout position contacts, etc. Write down whatever colors you choose, and be sure to use the stick to your standard. It will make later troubleshooting or modifications much easier to deal with.

Also, it is much easier to work with such an assembly if you don’t route the wires randomly from point to point. If this frame is mounted below your layout, route the wires to the layout up between rows of connectors and out to the layout. Route connections between connectors down below the connectors, horizontally, and then up to the proper pin. Be neat and orderly, and, except for train running circuits with a detector board such as our BD8 or BD16, use small wires. For LED’s and typical incandescent bulbs, 24 to 30 gauge wire is fine for reasonable lengths, say less than 100-200 feet.

Recommendation: that you use stranded wire for connections out to the layout, since those wires are likely to be flexed and moved. For wires simply connecting from connector to connector, especially if you are using a group frame as shown below, solid wire is recommended. It tends to hold its shape, and can be routed neatly from point to point. When all the wiring is done, use tie wraps or cable lacing twine to bundle the wires and provide a strain relief.

Then connect the power supply provided with the MSC to the card edge connector. The power supply has a cord with a low voltage DC output. As you receive the power supply, there is a plug attached to the end of the cable. Cut off the plug as close to the end of the cable as you can. Split the two wires back from the end for about 1 ½ inches, strip about ¼ inch of insulation from each wire and attached them to the card edge connector. The wire with the white stripe gets connected to pin 18, the positive power input. Connect the other wire in the power cord to pin V.