Let me start off by telling how the project started. A project which took over 3 years to complete, but I spent a lot of time just thinking about it. In 1997 I got my CPL and in 1998 I flew on the PA31 series, and I wanted to be able to practice engine failures in FS. I would need 2 throttles, 2 prop controls and 2 mixtures. FS2000 was just released when I realised that the possibility existed to use more than 4 joystick axes in FS. I went ahead an bought 2 USB 4 axes joysticks in addition to my Suncom stick and throttle combined with rudder. I configured FS to see if it all worked as I hoped, and it did...YES! Now to build the hardware. Easier said than done, a lot easier...

I planned to take the joysticks apart and use the electronics and replace the potentiometers with standard ones (most joysticks use 100k Ohm). I bought the Logitech wingman extreme digital 3D which was a USB device with 4 axes. I knew Logitech used potentiometers because I already converted a Wing Extreme Digital into a steering wheel for car racing games. MS used some kind of optical technology which seemed a bit hard to modify.

Now I just needed to built a throttle quadrant. But I still had to design it. I thought it would be easier to built a radio panel to use all those buttons on the joysticks that I had. Seven buttons on each stick plus using 8 different functions on each POV hat switch. (Some may remember an op-ed on this subject). 7+8=15 15*2=30. That equals an awful lot of functions. I would be able to make control com1, nav 1&2, ADF, as well as the A/P. Pete Dawson had published a list of FS controls which were not available in the assignments menu but could be added to the fs2000.cfg. That's how I would get it to work.

Building The Radio Panel

This is the layout I chose. The numbers indicate the button number. The v/s button was not installed. Most rotaries got 2 numbers, one button to increase and one to decrease. The ADF buttons only got one each cause I ran out of buttons. The rectangles represent push buttons and the circles represent rotary switches, or something, yes, or something. That's where the trouble started.

The First Electronics Purchase

I went to a kind of radio shack and asked for a rotary switch that would repeatedly short one contact when turning one way and vice versa. I picked up my order and got home and started to connect my switches to the joystick electronics. First I connected one to try. Well it didn't work. Only after I gave my rotary switch an aggressive spin did it seem to react, but with no regard for left or right. When I got back at the store for advice the guy uttered something about gray-codes and other stuff I did not quite understand.

Lows, More Lows And A High

My project was at a standstill. Even before it got a chance to take off. I spent some time on circuits to get it working because it needed something to interface between the rotary encoders (that's what these things turned out to be) and my joystick hardware. At one time I found some circuitry on an FS cockpit homebuilt site which I decided to try. I needed a certain IC but was unable to get it here in the Netherlands. I ordered it over the internet and was treated to an economically packed and delivered package including my IC. The IC was about the size of a your average domestic spider but it was delivered in a box large enough to ship the shoes of crusty the clown and it was weighed down with a 150 pages catalogue. IC costs 3 USD, Shipping 42 USD, Argh!

Last time I did that...

I got my soldering iron out, and carefully tried to reproduce the circuit. It did not, I say again, it did not work. Bummer...

I was fortunate to accidentally meet with someone involved in homebuilt FS hardware and he presented me with the solution. I got a nice schematic via snail mail.

Thanks to Ron Norp.

The top part is of interest to this project. The middle part is just a way to connect micro switches to joystick or keyboard. The lower part are the mechanics to a mixture control using an encoder in lieu of a potentiometer. The switches provide a means of mix. Full rich or idle cutoff. The 4093 IC is drawn as separate components but the numbers indicate the pins on the IC. The 4093 also has 14 pins.

From Turn To Push

When I built this schematic, it worked like a charm. Depending on your own requirements you can change the value of the resistors which are connected to the capacitors. This will alter the duration of the contact made by the CD4066. I found that changing only the value of the resistors had quite a big influence. There is a balance between a short pulse where the joystick driver sometimes misses a "beat" and the maximum rate of the pulses. It's best to experiment with different values. The CD4013B, CD 4093 and CD4066 are shown as two devices which are actually one. The numbers indicate the numbers of the contacts on the IC. Reading datasheets usually clarifies these schematics. Datasheets are available on the websites of most semiconductor manufacturers. When using FSUIPC you can chose to fix control acceleration in FS. I did not use this. That way e.g. my heading bug starts to turn slowly at first but when I continue to turn the knob it speeds up. Saves a lot of time on large turns. This works well for altitude and speed selections. Just experiment and see what works best for you.

The pictures show the actual circuit board with circuits for 6 encoders. On the edges of the board are the 4013B's. Working to the middle of the board are the 4093's with the capacitors (red and blue) Notice that there are only 6 4066's in the middle row of the encoder circuits. (there are 3 more for another purpose, more on that later) You can use 1 4066 to make 4 separate contacts. 1 encoders will control just 2. So, one 4066 per 2 encoders. I tried to make an economical arrangement on the board. I soldered strips on the board instead of using a lot of wires. These can be seen on the lower picture. They run across the board to provide +5V or ground. These soldered strips connect the +5V to the power connection of the IC (always pin 14 for + and 7 for - as indicated) Speaking of voltage, I draw power from the joystick USB connection which is 5V. Isn't that convenient? The encoders are connected to the 3 pin connectors. The 4 pin connectors next to the 4066's are used to connect the board to the joystick circuits.

If you can count you've seen more than 6 encoders on the radio panel. That's why I made 2 of these boards. Each one draws power from its own joystick. So one circuit board is connected to one joystick. This also applies to the buttons. This prevents strange behaviour of the joystick software like not recognising it, etc. This is now not entirely true anymore because of additions I made to the panel. But you may need to connect your devices in a certain order to prevent trouble. I must say I have had little trouble in this respect. Speaking of which, I noticed accidentally that the USB port is relatively safe with respect to short circuiting. It happened to me several times without any damage. I got a good scare once when after experimenting a bit, my PC would not start. I turned out to be a disconnected power cable to my PC. Phew... So don't comma crying after blowing up your precious PC. Read the included disclaimer.

These are the guts of the radio panel. Built into a project box without major alterations. Suction cups were donated by a 10 year old joystick (which had been turned in to rudder pedals during FS4). The ribbon cables which connect the encoder circuits to the joystick can be seen. Inside are 2 joysticks and one game pad, which was added for extra functions. I used this to be able to turn the AFD knobs both ways and add stby/use buttons to the radios. Also the flap switch which is on the throttle quadrant uses this game pad.

Happy Happy Joy Joy

My encoders worked after a few long hot nights sweating over a hot soldering iron. Nothing worked right away and I've spent quite some time troubleshooting all these circuits and finding the solution in a bad contact here and there. Some time after completion of the panel I ran into an other problem. With the arrival of FS2002 the POV was no longer usable for more functions than one. This presented a problem until Pete Dawson came up with a way of programming joystick buttons in FSUIPC.

This is the final version of the radio panel. It features a few extra features compared to the original design. I used a Wingman Action Pad as a donor. The switches are spring centered and have to pay a little attention what the position of the FS switch is. Pushing the switch up or down will press just one game pad button. Sby/use buttons are normal buttons. To use the POV of the game pad for 8 different functions I used a circuit including the 4066. this circuit will be explained later on.

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