May 2008.   I finished building the SimMotion Overhead Panel several months ago, but was waiting for 
the right opportunity to remove the Symulatory Overhead and replace it with this one.   Then with the appearance of Pete Dowson's new v3.81 of FSUIPC which allowed me direct control over the overhead switching without seeing the panel, made me do the business. For more Info on what I did with FSUIPC here, refer to the User Manual section on Macro's and also see the Controlling PMDG below.
CONSTRUCTION
The Panel has been assembled onto a simple wooden frame (painted grey of course).  It has been assembled into the shell and hinged at the rear so it can be lowered for maintenance and for the addition
 or upgrade of any switch or annunciator system (a 'Must Have').  You have to be able to work on it easy.
Rear Overhead. 
As of the time of writing, the Rear Overhead Panel is completely Dummy with the Exception of the Dome Light Switch and the Three Landing Gear ANNUNCIATORS which are driven from the CPFlight MCPEX1 Board.  When Time and software permits, I'll get on to doing  something further with more functionality.
Forward Overhead.
What I have tried to achieve here is as close to reality as i can without resorting to expensive, dedicated  software/hardware. The result is pretty damn good, even if i say so myself.  Just about every annunciator is lighting as it should based on the position of the switches and each switch is wired to simple input devices -  Leo Bodnar's BU0836X Joystick Controller which is now capable of handling Rotary Encoders.   This coupled with Pete Dowson's new FSUIPC Mouse Macro's allows me FULL control of the PMDG Overhead Panel without ever having to see it.
POWER SUPPLY
Now it's built, it time to get some power onto it. Look no further than an ATX computer Power Supply. This is going to deliver the 5vdc and 12vdc you need to get juice onto the overhead.
Ok, so there are so many wires coming out of it, but we are only interested in the following........
BLACK = 0vdc    RED = 5vdc   YELLOW = 12vdc  and GREEN = SWITCH.
Connecting the Green wire to any Black will start the Power Supply and breaking the contact will turn it off.  So I have used
 the Battery Switch on the Meter Panel to do this for me.  See the illustration in the left column.

VERY IMPORTANT NOTE
Right, what i have done is this. Where necessary, i have used a DPDT switch.  One side is connected to the BU0836X as the input and the other side is controlling the voltage to the annunciator. On the left is an image of a DPDT (can also be Centre Off) Switch.  Click on the thumbnail to see a close up of it.  A lot of people dont understand what happens using this solution.   Basically, a DPDT switch is two seperate switches in one casing.  In this example, SW1 and SW2.   Where a switch has to control the software switch and the voltage to the hardware annunciator, this is the switch to use. SW1 will control the input to the controller card which then gets FSUIPC to action the macro and SW2 will turn the power on and off to our annunciator.   Some switches do not have an annunciator associated with them, so a simple SPST switch can be used.   You have to understand what switch does what before you continue.   See the SwitchMap document for help in choosing switches.
The left column below deals with the power distribution and the right column tells you how to connect your switches.

POWER Distribution Ok, now you're turning it ON and OFF, the next Job is Getting Power round the panel to feed all the switches/LED's.  This is how I did it.   I broke it down into two sections, the POWER DISTRIBUTION and the BUS.      POWER DISTRIBUTION is the most complicated to achieve because it has to follow a given sequence of what lights up when this happens or that system is turned off. So we'll deal with this first. SYSTEM Switching My aim is to make it realistic, yet as simple as possible. So there has to be a compromise somewhere.  There are several sources of power available to the crew of a 737 aircraft. Main sources being Battery, Ground Power, APU and Engine Generators.  So to simplify matters, i decided to use a rotary switch on the meter panel to distribute my 5v to the various systems.   There is a Switch position here for both ENG Gens APU and GND PWR, so let's start here.  I'm hoping to automate this but I just don't seem to be able to find the time to sit down and get playing with relays and switches.  But watch this space. GROUND POWER  When Ground Power is available, the selector is turned to the GND PWR position on the Meter Panel.     5v is routed to the Ground Power Available Switch (Lighting the BLUE GND PWR Avail  Annunciator). Pushed Down, the switch then routes the 5v to the  Distribution BUS (See Left Document) APU After starting the APU, the selector knob is turned to the APU position.  Power is routed to the APU Generator Switches which control the Blue APU Gen annunciator and deliver power to the BUS based on the position of the switches.. ENG GENS    After Eng start, turning the Power Distribution switch to either of the Eng Gen positions routes the voltage tru the DRIVE switches to the Eng Gen Switches.  ENG Gen switches OFF, Source Off and Eng Gen Off annunciators are illuminated. Eng Gen switches ON, voltage is delivered to the BUS. DISTRIBUTION CIRCUIT DIAGRAM PDF    Click one of the pictures above to download the Distribution Circuit Diagram PDF file for a better insight into how it all comes together.  The Overhead NOTES are HERE The BUS.   I've managed to get to start the BUS document, so i thought i'd upload what i have so far.  If nothing else, it will give you the general idea of what is going on and how to start connecting your switches. ** Added March 16th 2009.  Here's the First few pages of the BUS circuit.  I'm already on with the next few pages, but several people have been on at me for the document.  This is the most complex part of the overhead and it will give you a good idea of how i am doing things and getting the circuit to work.  As i complete the next section i'll upload it.  But as always, it's my hobby not my job :o))   SWITCH TYPES Here we go....this is where it gets serious. You have to have a PLAN. Don't go blindly off soldering bits of wire to switches and make it up as you go along. That is going to end in frustration and tears.  Think about what Overhead Panel Switches you want to operate and HOW.    What switch is going to be connected to what interface.    How does that interface respond.   Is it a joystick controller or a Keyboard Emulator or a dedicated piece of I/O hardware? This is where you now have to formulate your plan because no two cockpits are identical and as we suffer from a distinct lack of standards in this hobby, everybody manufacturing a hardware interface system is going off in their own direction leaving most of us bewildered.  You have to make a decision whether you are going to go with one of the commercial solutions or are you going to make it yourself.  Bad things happen if you make the wrong decision.   By doing it myself, support lives in the same house as me :o)) On the left is a link to the types of switches that are readily available. These are what i have used in my overhead panel. Type 1 is a simple Push to Make Switch making it ideal for Attendant and Guard Call or the Test Button on the AirCon Panel.   Type 2 is again a simple ON/OFF Toggle Switch which can be used for any switch function that does not require the control of the voltage at the same time (e.g. Landing Lights, Taxi Lights, Anti Collision and Nav Lights. Also used for the Recirc fans.   Type 3 is a Two Pole Switch. These are available as ON/ON, ON/OFF/ON and as Momentary Switches (ON)/OFF/(ON).  Ideal for lots of applications because they connect two different continuity circuits in one switch. The Momentary switch lends itself to the No Smoking and Seatbelts application because they are spring loaded to centre and no power needs to be controlled. Type 4  Now we are cooking :o).  This is a Double Pole, Double Terminal Switch.  It's basically two seperate switches in one housing.  This now allows us to control the voltage on one side and the input to our interface device on the other. Ideal for use on every switch that is used to input to the interface card and control voltage whether it's for routing or to light an annunciator. The above example is the Eng Gen switch. One side signals our interface to action something (in this case the Joystick Controller) and the other side switches the 5v to the Eng Gen Off Annunciator. For More Information on What Switch To Use and How To Connect It, Download the Switchmap Document in the left column.

Controlling the PMDG Overhead With Hardware May 2008, Everything has changed! Pete Dowson has just released his FSUIPC v3.81 which includes a function on Mouse Macro's.  Pete uses a routine called 'Mousetrapping' which reads your action with the mouse and allows you to record that action as a code and not as a mouseclick. It then follows that that action can be applied to almost any switch or gauge WITHOUT IT BEING IN VIEW :o)    So, you do not have to open the PMDG OVERHEAD PANEL to action the switches (nor the Radio Panel or MIP either).   You have to have a Registered version of FSUIPC to do this, but it's great value for money. By registering, you not only keep Pete Dowson developing, but it also means he will continue to support you. Included in the Downloaded FSUIPC.zip is a file called 737 OHD.mcro.  What Pete has done is map all the switch actions on the PMDG Overhead and create macro's for them.   When you copy the .dll file to your FS/Modules folder, you take this .mcro file as well and when FS/PMDG is started all the 737 OHD macro's are available to you in the Button Press and Keystroke Dropdown Menu's - BRILLIANT ! But it doesn't end there.  Pete has also included the ability for us to write our own macro's as well, but that's another story for another day :o)) CONNECTING YOUR SWITCHES Now everybody knows i'm a great fan of Leo Bodnar's BU0836 family of Joystick Control Cards.  So it was a natural choice for me to connect up the first 32 switch actions thru the new BU0836X board. What this board does is make Windows think it's a Joystick with 8 analogue Axes and 32 buttons (bit like a 'barebones' SAITEK X45) which can be tested in the Game Controllers Page in the Control Panel just like any other Joystick. So by connecting switches and pushbuttons to the numbered button inputs on the card, upto 32 button presses can be sent in.   Then of course FSUIPC is able to action one command when the button is pressed and another when the button is released giving us two actions on one switch if we need it. Here's an example, the Eng1 Gen Switch. Connect a simple On/Off Toggle Switch to any input on your controller card (it doesn't have to be a BU0836X) and start FS with the PMDG 737NG loaded.   Now open FSUIPC and go to the Buttons & Switches page and turn the switch ON.   FSUIPC will see the switch action and identify it as Joy#, Button#.  Once your input has been recognised, tick the 'FS Control' box and then select the '737 OHD: Gen1 On' item in the dropdown menu for when the button is pressed and the '737 OHD:  Gen1 Off' item for 'when the button is released'.   You now have two actions from one switch, go on try it.  Good isn't it. Here's another example, the Seatbelts Switch. What we have here is a different type of switching.  It is a two action on and off switch which is spring loaded to centre. So for this type of switch, i needed to use two inputs.  One for the UP and one for the DOWN (the No Smoking Switch is the same). So i used two button inputs and shared a common ground connection to give me the two inputs i needed.   Then it's off to FSUIPC to identify the input and assign the action (as previously). And finally for my mate Alan Watson (who has a thing about this), a final example is the Attendant Call Button.  A simple push button that when pressed emits the famous Boeing Chime.  Connect a simple push to make Pushbutton to one input on your controller and assign it in FSUIPC to the '737 OHD: Attend' item. Simple. USING ENCODERS Leo has now upgraded the BU0836 family of controllers to accept inputs from Rotary Encoders, so it then follows that Inrease/Decrease Rotary Controls (like FLT ALT and LAND ALT) can now be utilised as well.  If you have purchased a BU0836 card this year, the firmware will already be in place. You can get the configuration program to assign inputs on your BU0836 card HERE.          I use two types of encoder for this type of Input, the CTS288 from OPENCOCKPITS and also a cheap Chinese Encoder from Sure Electronics on e-bay (he's real cheap on LED's as well and his Amber one's are pretty good too). Once you have assigned switch pairs in the BU0836_encoders.exe utility, your card will read the direction of rotation and translate that into repeated joystick button presses based on direction at one press per detente.    So for repeated presses, simply continue to turn the encoder. And there's more:- Ok, so we have most of the controls working, but one or two still give us a problem. For example the Wipers.   How do we accurately control this type of switch.   Read this document for the solution to the problem. Can also be used on the AUTOBRAKE :o)) MAKING SIMPLE ENCODERS Click an Image To See Some Build Photo's e-mail us