Automatic Block Signal System
Assembly Notes and Instructions
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Preliminary Considerations:

 Electronic components are sensitive to static electricity, excess heat and physical abuse (dropping, crushing, etc…)

 Please prevent anything like that from ruining your project.

Assembly of these boards requires at least a basic understanding of soldering process, component forming (pin bending) and placement of components. Installing a component in the wrong location will most likely prevent the unit from working and could easily damage the other components which will probably ruin your day.

These are SMALL boards that use SMALL components. The temperature used to solder the components needs to be controlled. The minimum requirement is to use a soldering PENCIL rated at 35W or less. A soldering GUN is not acceptable for component installation, please do not try this, as failure will become more likely.

 Use thin, low temperature solder. The thicker the solder, the hotter the soldering pencil needs to be.  

ONLY USE ROSIN CORE SOLDER. Acid core solder is great for plumbing, but will erode the metal pins connecting the components. 

If you bought a Circuit Board DIY Kit, it came with the basic components: Resistors; Transistors; Integrated Circuits (DIPS); Diodes; Capacitors; Berg Pins and Power Terminal (where necessary). 

If you just bought the BARE Circuit Board, refer to the list of necessary parts. All of the parts are available from our web site as well as normal suppliers like Radio Shack.  

Component Identification:

  All of the components have some method of identification. 
The circuit boards have a legend silk-screened on the surface to help guide you in placing the components. 
You will need to bend the legs or leads of each component so it will fit into the holes provided. 
Most components will actually touch the circuit board.

 Diodes are the small, cylindrical parts with a glass body. They have a black band on one end. The circuit board has a picture of a rectangle indicating the location of the Diode. One end of the rectangle has a small block designated. This is the end that the diode’s black band needs to face. 

 Resistors are marked with different color bands to specify the resistance value. I provide the color codes for each resistor at the end of these instructions. It does not matter which way the resistor is installed, but we normally point the fourth  (4^th) band the same direction. This is mostly for cosmetic appearance.

Transistors are labeled with their number and it is important to be certain that you use the correct transistor in the correct location. The circuit board has an illustration for each transistor and it is shaped like a “D”. If you insert the transistor so the case matches the illustration, you will be OK. You want to gently push the transistor down to get as close to the board as reasonable. Usually around ¼ (.250) inch is good.

Dip is the name associated with Integrated Circuits (ICs) and stands for Dual, Inline Pin component. The dip has a notch at the FRONT of the device and also a small dot or circle at the upper left-most pin area. The dot designates Pin #1. If you can’t see the dot, just position the Dip on end, with the pins facing away from you and the notch at the top. Pin #1 is the top, left pin. The Dip Socket also has the notch at one end and pin #1 is the same as that on the DIP. Please be careful to install the socket and ultimately, the Dip in the right direction. The legend has the notch pictured for clarity.

Capacitors come as either radial or disk shape. The radial capacitors are polarity sensitive and MUST be inserted the correct way. The circuit board illustration shows a + symbol designating the POSITIVE pin of the capacitor. The radial capacitor, however, has the NEGATIVE pin marked by a band from top to bottom adjoining one of the pins or legs. This band will have a minus sign (-) in the band. You must remember to insert the capacitor so the negative pin is NOT in the Positive hole. Disk capacitors don’t matter which way they face and there is no mounting convention, even for cosmetic appearances.

Berg Pins are simple connection devices and work with a variety of ready made cables or wire-wrap scenarios. You receive them in a single strip and you cut them to the length required. You can use a razor knife (CAREFULLY) or a small pair of diagonal cutters to cut the strips to length. They are notched between each pin to make it easy to know where to cut them. Several of the connections call for a Three (3)-pin, FOUR (4)-position plug. ONE (1) pin is missing, from position #2. This is a method of establishing proper attachment and polarity. The socket going over the plug normally has a corresponding blank space, which is often plugged so the socket will only attach in one direction. You can create the FOUR (4)-position, THREE (3) -pin plugs by carefully pushing the extra pin out of the plastic base. Sometimes, you might need a pair of needle nose pliers, but usually, the pins move with only moderate pressure. Use of a Berg Jumper and a TWO (2)-pin plug  makes a simple switch.

Any other parts to be installed are reasonably self-explanatory. If you are going to HARD WIRE the boards to each other, you will most likely want to forego the Berg Pins and solder the wires directly to the holes in the boards.

Most installers use 22 to 26 gauge wires to make the connections between boards. You can find cables with wire in these sizes at Lowes, Home Depot or similar supply. Look for their Thermostat wire, Telephone supply wire (CAT-3) or Network system wire (CAT-4 or CAT-5). If you need to keep your layout modular and easy to transport, you will want to use some removable type plug connections. The boards are designed to use Berg Pins as connectors. Berg socket type cables are available from our web site or from other companies that provide computer cables and connectors.

Assembly Suggestions: 

Check that you have the correct parts before starting. Lay them out in the order you will install them. 

Bend the legs to allow the components to fit in the holes provided. 

Remember to insert the components as shown in the illustration on the board. Diodes, Transistors and (usually) Capacitors are polarity sensitive, so be careful to get them installed correctly. 

Start with the smallest component (usually the Diodes). Solder the current group and trim the excess leads after they cool. You can "tack solder" the parts from the top and then turn the board over and finish up from the bottom. Continue board assembly using larger and larger components. Transistors and DIPS are very sensitive to static and heat. Be careful when soldering the Transistors and don’t keep the heat on the connections any longer than absolutely necessary. For DIP installation, you received a DIP socket in the kit so you won’t damage the DIP with excessive heat. If you didn’t buy the DIY Kit, then be sure to use a DIP socket. Be careful inserting the DIP into the socket. The pins are usually spread out a little too far and you will need to gently squeeze them closer together so they are more parallel to each other and will then fit the socket. 

Once finished, clean the board of any excess Flux using Flux Cleaner from Radio Shack or Brake Clean, ElectroMotive, or similar non-caustic type cleaning spray from your local Auto Parts Supplier. DO NOT USE CARB CLEANER. It is way too strong and will soften plastic and remove the silk-screened legend.

Testing and Verifying: 

Test each board using a power source not exceeding 12V DC - a 9V Battery works fine.  

Event Controller: Test the board by making a test LED that has a 1K-Ohm resistor connected to either of the LED legs before connecting a wire to the resistor and other leg of the LED. Connect the other end of the wire to the OUTPUT (O1 thru O4) of each channel remembering the outside pin on the connector is the POSITIVE (+) - the LED’s long leg goes to the OUTSIDE connection and the short leg goes to the INSIDE connection.   

When you attach 12V DC to the power connection, the LED will turn on. To make sure the Event Controller is working, you can connect the Output’s corresponding Input’s Pin #1 and Pin #4 together and the test LED will go out. BE CAREFUL NOT TO CONNECT PIN #2 to either pin #1 or pin # 4.   

You can also make up a SINGLE Sensor test cable by using one of the THREE (3) Connector cables available from our website or computer supply houses. These cables were used to connect the audio from a computer's CD ROM drive to the sound system in the computer. You need to connect a 470K Ohm resistor from pin-2 to pin-4 at the short cable. You connect the sensor between pin-1 and pin-4 of the far end of the cable (with the LONG Leg going to pin-1). The near end of the cable plugs on the THREE (3) pin, FOUR (4) position plug for the switch Input Channel that matches your chosen Output Channel.

There is a small mistake in the label for the output connectors on the Event Controller. 
The connections are currently marked O1, O2, O3 and O4 from the bottom up. 
Due to a layout mistake, the correct order is really O2, O1, O3 and O4. 
The right hand picture shows the correct sequence, but your board will look like the one on the left.
The Input connections are labeled correctly.

Although your board is labeled like the one on the left, it REALLY should be labeled like the one on the right.
Please remember that despite the labeling, the CORRECT order is 2 then 1 then 3 then 4. Thank you.

MultiSense: After assembly, verify that all of the DIODES are installed correctly. Install the jumper on the connection marked JMP1. Connect at least one sensor to the board. The LONG leg of the sensor gets connected to the outside connection and the SHORT leg gets connected to the inside connection. Jumper any sensor connection you are not going to use.  For more detail, see the write-up of the Signal System on our website: Signal System or MultiSense Info. Connect the MULTISENSE board to the Event Controller using the mutual Three (3)-pin, FOUR position (one pin missing) connections or hard soldering your wires between the boards. Using the powered up Event Controller and the test LED from above, you can verify the MultiSense is working by blocking and unblocking light to the sensor and the LED at the Event Controller will go off and on: OFF when the light is present and ON when the sensor is in the dark. 

Signal Light Controller: Install the signals or lights that you want to use. The LED OUT connections share a common ANODE (+ connection) so if you only have FOUR (4) wires coming from your signal, one will be marked COMMON, POSITIVE or ANODE and you can connect it to any of the three connections marked “+”. If you are using regular LEDs that have both leads present, remember, the LEDs are polarity critical so the Long Lead goes to the PLUS (outside) connection (and the GROUND (inside) connection goes to the Short Lead).  

Connect 12V DC to the POWER Connection. 

On the New Revised Controller, make sure the PLUS (+) wire goes to the LEFT side connection (toward the outside of the board) and the NEGATIVE (-) wire goes to the RIGHT side connection (toward the connections for the Prior and Next Boards).

On the Original Controller, the PLUS is the RIGHT side (toward the outside) and the NEGATIVE wire goes to the LEFT side connection (toward the Next connection).

The RED LED should be on. If it is, move the NEGATIVE connection from the POWER Connector and touch it to the GREEN IN (GI) Connection. The GREEN LED should light up. Move the NEGATIVE again to the YELLOW IN (YI) connection and the YELLOW LED should turn on.  

If that works, build up the other Signal Light Controllers that you will be using and attach the Signals or LEDs. Interconnect the Signal Light Controllers using the Previous and Next connections. Make sure that you connect GI to GO and YI to YO. Connect a common (the same source), POSITIVE (+) POWER wire to ALL of the controllers. Connect  a NEGATIVE (-) wire to the DETECT (NEGATIVE) connection of the POWER Connector for the first Signal Light Controller. The RED LED for that controller should turn on and the GREEN LED for the “NEXT” controller should illuminate, as should the YELLOW LED for the “PRIOR” controller. Go around your layout and apply the ground to every Signal Light Controller and they should ALL work the same way.

Connect the your detection system's NEGATIVE (-) wire to the DETECT (NEGATIVE) connection of the POWER Connector for the first Signal Light Controller.

Move the NEGATIVE to the next controller and repeat the test.   

Final Assembly:  

Now that all of the boards have been tested, you can install them and make your final connections. On small layouts, it might be easier to use cable assemblies that take advantage of the Berg type connectors. On large layouts, it is probably too costly to use those types of cables, so other connection methods should be employed. One choice is to hard connect each circuit board to the other using wires soldered to the connection points. Another method is to use a “Wire Wrap” tool and wrap 24-gauge wire around each Berg pin as needed. This is labor intensive, but it makes repair, change or replacement of boards a lot easier than if they are soldered together. 

The basic process for the System Assembly is very simple: 

If installing our complete system,

1. Install your Signal Lights. Connect them to their Signal Light Controllers.  

2. Install your sensors and connect them to the MultiSense boards (remember to put a jumper across any unused Sensor connections).  

3. Connect the MultiSense boards to the chosen channels on the Event Controller. 

4. Connect the matching output from the Event Controller to the input of the Signal Light Controller. Outside pin (+) of the Output goes to the PLUS connector of the input connection. 

5. Connect the Next connections to the Prior connections of the board next in the normal rotation of the train. Eventually, the LAST board will connect its Next plug to the FIRST board’s Prior Plug. 

6. Connect “common” 12V DC power to the Event Controller so all Positive connections are from the same source.   

If installing your own detection system, 

1. Connect a common (same source) PLUS (+) wire to every Signal Light Controller. Remember, it MUST be the same PLUS that goes with the detection system's Negative (-).

2. Connect the output of your detection system's NEGATIVE (-) wire to the DETECT (NEGATIVE) connection of the POWER Connector for each Signal Light Controller. If your detection system provides a PLUS (+) and NEGATIVE (+) output, you can use that PLUS (+) to supply each Signal Light Controller, but it must be from the SAME source for ALL Signal Light Controller.

Test each “BLOCK” by covering each sensor in every block. When ANY of the sensors in each block are in the dark, the RED light of that Block Signal will be on. The GREEN light of the next block’s signal will be on and the YELLOW light of the prior block’s signal will be on. 

Go around the layout and this should be correct for every block. When two adjoining blocks have a long train partially in BOTH blocks, BOTH RED lights will be on and the next block from the furthest block will be displaying GREEN and the block before the first one occupied will be YELLOW.

Sensors:

Just a quick note on installing sensors: Install sensors separated by a distance that is LESS than the shortest train you will run. To prevent the system from blinking as the train starts to enter or leave a block, install the SECOND and SECOND TO LAST sensor within a distance less than the length of your shortest car. This will guarantee that at least one sensor will be covered while there is a train in the block.

Now, it is time to run your railroad and enjoy the results of your hard work. If you have any problems or questions, please send an email to our Support Department or by using the "Contact Us" menu choice. 

Thank you for visiting, you are welcome anytime.

The Resistor Color Code: 

The first two bands specify the numerical value. The third band specifies the number of zeros. 4.7K Ohms is really 4700 Ohms (Yellow, Violet, Red). The easiest way to remember it is to use the value above to denote how many ZEROs to add to the number. Black is NONE, Brown is ONE, Red is TWO, Green is FIVE, Violet is SEVEN and so on. The fourth band is for tolerance and usually will be GOLD meaning 5%. 

Here are the codes for the most common resistors in the kits: