Hardware

Hey Everyone, it has been a long time since I did an actual pinball related blog post, so here it is!  I have been getting a ton of questions lately on how to properly power opto transmitter LEDs and how to hook up the receivers to the SW-16 P-ROC boards.  I am going to walk through it in enough detail that you should be able to get up running on the concepts quickly.

Powering Opto Transmitters

Opto transmitters are nothing more than high powered infrared LEDs.  For this guide, I am going to be referring to the Williams/Bally style opto transmitter which can be seen here: https://www.pinballlife.com/index.php?p=product&id=170.  This LED emitter has no circuitry attached to it by default.  These LED emitters are also used on the small PCB and bracket assemblies seen here: https://www.pinballlife.com/index.php?p=product&id=168 and other various trough board assemblies.

In order to safely power this LED, you will need to gather a few data points and make a couple small decisions.  You will need to know the forward voltage of the LED, maximum constant current that the LED can handle, decide what input voltage you would like to supply to it (5v or 12v), and decide how much current you would like to give the LED to ensure it has enough power to transmit infrared light to reach your opto receiver.

So here is our data:

  • Forward Voltage: 1.7v
  • Max Constant Current: 100ma, but I recommend you do not exceed 75ma to maximize the life of the LED.  This will be powerful enough to transmit a pretty decent amount of distance between the emitter and receiver.
  • Input Source Voltage: 5vdc is my recommendation as it is higher than the forward voltage of the LED, and low enough that the resistor does not have to dissipate too much heat.

These LED emitters will need a current limiting resistor in series with them as applying 5v or 12v directly to the LED will cause it to overload and fail.  Now, to calculate this resistor value, we will need to calculate resistance and power based on the data that we have.  Now, I could be idealistic and talk about the actual calculations, but I am going to show you how I usually calculate this using an online LED resistor calculator.  The one that I use the most is the one below.  I have already filled out the fields, but feel free to change some of the values up to see what happens.

http://led.linear1.org/1led.wiz?VS=5;VF=1.7;ID=75

So as you can see above, the calculator has automatically figured out what the ohms and recommended resistor wattage should be for our emitter.  What I also like about this calculator is that it gives a nice visual representation of how to wire the circuit and what the resistor color bands are.

Important note: Please be sure to use at least the recommended resistor wattage.  You can see above that the calculator is recommending at least a 1/2 watt resistor.  Too small of a resistor and it can burn up, which is bad.  🙂

That is about it for powering an opto emitter!

Connecting Opto Receivers to the SW-16 P-ROC Board

Now for this section, I am going to be talking about the Williams/Bally style opto receivers and how they hook up to the SW-16 P-ROC switch boards.  These are the black colored opto receivers that can be fond here: https://www.pinballlife.com/index.php?p=product&id=171.  These, just like the emitters, are also used in small PCB assemblies, and trough opto boards as well.

To connect these optos into the SW-16 P-ROC board, you will simply need to wire it directly to the inputs of your switch board.  It is really that easy.  It will act just like a standard switch as long as it is connected in the correct orientation.  Below, you will see an image from the P-ROC documentation.  The cathode/ground side of this diode is the side with the flat indentation on the black epoxy base of the opto.  Please also keep in mind that opto receivers are normally closed switches and when it detects the IR beam from the emitter, it will open.  This is opposite of a normal switch.  When a ball breaks the opto beam it will go from a closed state to an open state.

The full documentation can be found here: https://www.multimorphic.com/content/uploads/2017/07/SW-16-2_LLD_v2-0.pdf

I hope this all makes sense and helps you get your project up and running!  Please also keep in mind that some Stern and certain Williams trough boards have resistors built into them on the emitter side.  The guide above will allow you to connect to boards and directly to emitters that have no circuit logic.

Good News Everyone,

The Computer Startup / Shutdown Controllers are now shipping!!!  For more information including price, shipping, and options, follow the link below.

http://www.scottdanesi.com/?page_id=398

Please contact me with any questions you have.  Thank you!

20130609_191221Hey Everyone,
I just finished developing and writing up the latest version of my Computer Startup / Shutdown Controller.

What is this, you ask?

Check it out here for info including a demo video: http://www.scottdanesi.com/?page_id=398

Hey Everyone,

So I have been getting a few questions about how to properly connect an LED sign to my tournament software.  It is actually pretty simple and I will walk you through it below.

Supported Displays:

First things first, let’s talk about supported displays.  Currently, I have only tested the software with my BetaBrite 213C and my Alpha 220C.  These are some of the most common signs you can find that are affordable.  The BetaBrite signs also came included in the Tournament TOPS Kits from Stern Pinball.  I plan on testing other types and brands very soon.

Display Connection:

BetaBrite Connection Info2

This diagram illustrates the display connection to your PC

These signs use a serial (aka. RS-232 or DB9) connection to your PC.  This type of connection is now very uncommon and is most likely not included on that nice new laptop you bought.  Don’t worry though, many products still use this protocol and there are USB to Serial Adapters available for cheap.  I would recommend getting a USB to Serial adapter with the FTDI Chipset as I have not tested any other type.  If you are lucky enough to have a serial connection on your PC then this is not a problem.  I still like to use the USB to Serial adapter since it will also extend the range of the cable that came with your display.

Cable 1

BetaBrite Serial Display Cable

Speaking of which, you should have received a cable with your display that has a serial connection on one end and a network type plug on the other.  If you do not have this cable, don’t worry as they are inexpensive and can be found on eBay.

Once you have all the necessary cables you will need to hook them together and power up the display.

Configuration:

Configuring the sign to work with the software is probably the easiest part.  The one thing you will need to know is what “COM Port” number that your serial connection is set to.  This is a whole number that is usually under 10.  You can find this number by going to your control panel in windows and selecting Device Manager.  Your serial port will be listed under the “Ports” section and have the COM Port displayed in the title.

Once you have this port number, you can now open up the Tournament Manager application.  At this point be sure that your display is connected properly and powered on.  Click on the options tab and then click on the BetaBrite Options tab.  First select the COM port for your serial connection and then check the “Primary Display Output Enabled” checkbox.

Your display should show the test message!  From here you can setup a “Standby” message that will display on the BetaBrite while you are setting up the tournament.  You can use it to say when the tournament is starting and how much it costs to enter or whatever you want.  🙂

References:

BetaBrite Cables on eBay

USB to Serial Cables on Amazon

As always, let me know if you have any questions.

–Scott