Controlling Tortoise Machines with Momentary Contacts and a Diode-Matrix By Jerry Hoverson, MMR

1. Controlling Tortoise Machineswith Momentary Contacts and a Diode-Matrix By Jerry Hoverson, MMR

2. Controlling Tortoise MachinesWith Momentary Contacts Why the Tortoise switch machine motor in the first place • Easy to install • Reliable • Rugged • Provides slow, quit movement of points • Provides constant pressure to hold points against stock rail • Provides 2 sets of contact points • Frog polarity control • Panel indicator lights • Switch indicator signals • Has become the hobby standard for remote control of turnouts

3. Controlling Tortoise MachinesWith Momentary Contacts The biggest disadvantage of the Tortoise switch machine motor is that it requires a constant, reversible 9-12 VDC power source.

4. Controlling Tortoise MachinesWith Momentary Contacts So what happens if you try to control that turnout from more then one control panel with that constant power source? A SHORT!

5. 556 Controlling Tortoise MachinesWith Momentary Contacts Enter the 556 circuit!

6. Controlling Tortoise MachinesWith Momentary Contacts Where you can control the Tortoise with MOMENTARY devices Momentary DT Center Off Toggle Switch Momentary Pushbuttons - S 8 R 1 + 556

7. + 12 VDC R1 2.2K Reset 8 12 14 IC1 LM556-A 13 9 D2 R2 10K R3 10K Tortoise Set 2 6 IC1 LM556-B 1 5 1 8 7 300 ohm + 300 ohm D1 C1 10uf - - 12 VDC Controlling Tortoise MachinesWith Momentary Contacts Here’s the circuit diagram for those who just have to have one.

8. Controlling Tortoise MachinesWith Momentary Contacts OK, lets look at how we would install this on a simple track arrangement. Track A Track B Track C Track D MAINLINE

9. Slave Control Panel Master Control Panel - S 8 R 1 + 556 Controlling Tortoise MachinesWith Momentary Contacts One method is to mount the 556 circuits in one “master” panel and then connect additional “slave” panels to the master.

10. Controlling Tortoise MachinesWith Momentary Contacts What’s good and what’s bad about this method of installing? • PROS • 556 Circuit is accessible inside the control panel not under the layout • Multiple circuits can be ganged together • Single board • Single power connection with Positive and Negative 12 VDC buses • Only 2 wires going from main panel to Tortoise • CONS • Takes up real estate inside the control panel • Depending on other items may be difficult to get to connectors • Large number of wires going between each panel • Hard to add another tortoise once complete

11. Controlling Tortoise MachinesWith Momentary Contacts Here’s a “ganged” set of 556 circuits in a control panel.

12. Controlling Tortoise MachinesWith Momentary Contacts Let’s look at a general setup using a “master” panel. 2-Wire from Master Panel (1 & 8) for Tortoise movement Tortoise Tortoise Tortoise Tortoise 16-Wire from Slave to Master (S & R) for control of each circuit (1 & 8) for LED indicators for each circuit Slave Master 556 556 556 556 2-Wire (+ & -) 12 VDC 12 VDC

13. Control Panel B Control Panel A - S 8 R 1 + 556 Controlling Tortoise MachinesWith Momentary Contacts Another method is to mount individual circuits near each Tortoise Machine

14. Controlling Tortoise MachinesWith Momentary Contacts Why use this method of installation? • PROS • Frees up space inside the control panel • Multiple circuits can be ganged together if tortoises are close together (i.e. a yard ladder) • No massive bundle of wires between panels • Simple to add another circuit between panels • CONS • Takes 4 wires from each panel to the tortoise • Takes 2 wires to supply power to each circuit • Set up as a bus and daisy chained

15. Controlling Tortoise MachinesWith Momentary Contacts Here’s an individual circuit mounted near the Tortoise Machine

16. Controlling Tortoise MachinesWith Momentary Contacts Let’s look at a general setup using the individual 556 circuits mounted at the tortoises 4-Wire from Slave (S & R) for control (1 & 8) for LED indicators 4-Wire from Master (S & R) for control (1 & 8) for LED indicators 556 556 556 556 Slave Master 2-Wire (+ & -) power bus 12 VDC

17. Controlling Tortoise MachinesWith Momentary Contacts Now let’s take this a step further and implement a Diode-Matrix to control several turnouts with a single button. Otherwise known as “route control”. Track A A Track B B Track C C Track D D MAINLINE E

18. Controlling Tortoise MachinesWith Momentary Contacts To implement a Diode-Matrix you simply wire each button to an input on the matrix and the outputs of the matrix to the “S” & “R” connections on each 556 circuit We’ll start by numbering each turnout If we push button “A” then 1=R, 2=S, 3=S, 4=S The unmarked direction is then the “R” or Reset position A Then we need to determine which direction is Set “S” or the default position S 4 B S 3 C S 2 D 1 Mainline S E If we push button “E” then 1=S & we don’t care about the others

19. A B C D E A S 4 R B S R 3 3 2 1 4 C S 2 S S S S R R R R R R D 1 S E Controlling Tortoise MachinesWith Momentary Contacts Let’s take a few minutes and set up our Diode-Matrix • Remember, if we push Button “A” • 1 goes to “R” • 2 goes to “S” • 3 goes to “S” • 4 goes to “S” • if we push Button “C” • 1 goes to “R” • 2 goes to “S” • 3 goes to “R” • 4 we don’t care • if we push Button “D” • 1 goes to “R” • 2 goes to “R” • 3 we don’t care • 4 we don’t care • if we push Button “B” • 1 goes to “R” • 2 goes to “S” • 3 goes to “S” • 4 goes to “R” • if we push Button “E” • 1 goes to “S” • 2 we don’t care • 3 we don’t care • 4 we don’t care

20. A 556 #2 556 #3 556 #4 556 #1 B - - - - S S S S 8 8 8 8 R R R R 1 1 1 1 + + + + C D E A 4 3 2 1 B S S S S R R R R C D + 12 VDC E Controlling Tortoise MachinesWith Momentary Contacts So let’s wire up the Diode-Matrix with the 556 Circuits Connect the buttons and the 556 circuits to ground Connect the 556 circuits to + 12VDC Connect matrix outputs to the 556 circuits Connect the buttons to the matrix inputs And last connect the “1” & “8” outputs on the 556s to the tortoise machines

21. Controlling Tortoise MachinesWith Momentary Contacts OK, now that you’ve seen all the wonderful things a 556 circuit can do for you, what does it consist of and what does it cost?

22. Controlling Tortoise MachinesWith Momentary Contacts Here is what individual 556 circuits for mounting near the Tortoises looks like

23. Controlling Tortoise MachinesWith Momentary Contacts • The 556 circuit used in this presentation was developed by Rob Paisley • Rob has published a lot of model railroad circuits, for example: • Stall motor turnout controls like this one (several variations exist) • Automatic grade crossing controls • Traffic light control • Infrared detectors • Block occupancy detectors • His web site:http://home.cogeco.ca/~rpaisley4/CircuitIndex.html#index • If you are interested in building this circuit and trying it out there are handouts available that include: • Electrical diagram • Parts list • Parts layout diagrams • Detailed step by step instructions on building the circuit

24. Controlling Tortoise MachinesWith Momentary Contacts Q & A

25. 14 14 1 1 13 13 2 2 12 12 3 3 11 11 4 4 10 10 5 5 + 1 R 8 S - 9 6 9 6 7 7 8 8 - + + - - + Controlling Tortoise MachinesWith Momentary Contacts 556