For the following contributions we would like to warmly thank the respective authors. Only through a wide range of the connection descriptions is the Parallel port Interface System of FMS of use. If you know a Pin-allocation not yet specified here or connection circuit, we would be grateful for a short description. Neither we nor the authors of the following contributions take any liability what so ever for any losses in computer, interface or remote control or secondary damages of any sort.

I have suggested Michael to make a simpler option, to use a remote control as a controller for FMS, as the adapters suggested so far are based on complicated conversion of the remote control signals to a gameport-compatible signal or by opening the transmitter.

The basic idea is to connect the remote control transmitter simply to a PC.
If the transmitter:

1. Uses PPM-MODULATION (or it can be selected)
and
2. Has a "buddy-socket"

One only needs a Parallel port socket (25 pin Sub-D, male(pins)), a plug which fits in the buddy-socket of the remote control transmitter, approx. 2 meters lead in order to connect the remote control transmitter to the PC printer socket, as well as a resistance and a zener diode.

The diagram looks as follows:

                        +---------+
   A )------------------| 680 Ohm |---------*--------------------( Pin 10
                        +---------+         |
                                            |
                                          -----
    Buddy socket                             /                Parallel-
    on transmitter                          /\    ZPD 4v7     Port on
                                           /  \               PC
                                          ------
                                            |
                                            |
   B )--------------------------------------*--------------------( Pin 18

The ring of the zener diode must point to the resistance. The connections A and B are different from remote control to remote control. With the Robbe " Terra top " and the Robbe "Luna" from neuzehnhundertdunnemals are it in a "normal" 5-pole DIN plug the following Pins:

                2           viewed from the front on the plug, one sees
                o           the pins within a round screen
          5 o       o 4
                            (the plug I have has stamped
         3 o         o 1     numbers)

                -
              Screen

    A is to be connected with Pin 1 (signal)
    B is to be connected with Pin 2 (ground)
    the screen is not connected

A clever feature of these remote controls is if Pin 3 and Pin 5 are connected. If one connects these two pins in the DIN plug with a wire bridge, the digital coder part is turned on while the plug is in the transmitter but the HF-part is not supplied with power. If one has this type of transmitter one is lucky that no provision is required to prevent the HF-part from damage by operation without aerial. Also, the power consumption is much smaller without the HF-part.
If ones transmitter does not have such a connection , it is advisable to disable the HF-part by pulling the crystal while using with FMS.

Still two other transmitters were available to me: a Robbe / Futaba Skysport of 4 newer dates (bought 1997) and a Robbe 4-channel-arrangement of 1995 the names I do not know. These two enclosures have in each case a 6-pole plug for the Buddy connection. The allocation is as follows:

                3           views from the front on the plug, one sees
                o           the pins within a round screen
          2 o       o 4
                o           (the plug I have has stamped
          1 o   6   o 5     numbers)

                -
              Screen

    A is to be connected with Pin 4 (signal)
    B is to be connected with screen (ground)

(For the numbering of this sort of plug I do not want to take a risk, because this time there is nothing on it. If one considers, however, the plug from the front, also the cable of itself turns away, then it is the pin labled pin 4 in the picture above)
(To whom it interests: in both of these newer Robbe/Futaba-arrangements Pin 4 is the exit in the "pupil's-transmitter". In the teacher's-transmitter" this signal must be fed in Pin 3. Then with this one has a reasonable buddy-cable for these transmitters.
With the TerraTop or Luna there is no buddy socket, but a plug is available to be able to operate the Servos " on the ground " without HF-radiation. For this purpose was enclosed a cable which has a 3-pole "Servostecker" at the other end which was put in a special entrance of the receiver. But this, only by the way...)

If the allocation of the pins in the buddy-socket is not known, the user must ask either the allocation from the manufacturer or find a model construction trader who you can trust or measure by means of an oscilloscope. The pin on which one sees a rectangle signal with respect to ground with a period duration from approx. 1.5ms corresponds to connection A.

For whom the "circuit" design calculations interest:
I have assumed that a transmitter with 8 NC-cells is used. If these 8 cells are quite charged, with good cells in transmitter an operating voltage of no more than approx. 11 volts (1.34 volts per cell) is seen. Then after few minutes operation the voltage will fall to approx. 9.6 volts. Then according to Ohms law (V=R*I) the resistance can be found from (11V-4,7V) =R*0,01A Using the worst case with 10 mA of current across the zener-diode - > R=630 ohms calculated. The closest higher standard value is 680 ohms. Then the current will adjust itself in the worst case (battery fully charged) to 9.2 mA. The resistance will generate power of W=V*I - > P~58mW , so one can use normal 100mW type.
The purpose of the zerer-diode is to limit the input voltage to the Parallel port to a maximum value, which cannot do damage. Because the Parallel ports work commonly with TTL-levels, also with values of small 5 volts, here we use 4,7 volts to be on the safe side.
This consideration is applied to the case that the signal in the exit of the buddy-socket has a value of greater than 5 volts. If the signal is smaller, the voltage-limiting influence of the zener-diode disappears. In this case the sensitivity of the Parallel port input is the critical point. With the Parallel ports accessible to me (two Multi-IO-Karten and an Onboard-interface on an ASUS Motherboard) a voltage swing of 0,9 volts above zero has been sufficient to make the test programs of Michael work. However, the probability that the signal in a buddy-socket being so low level is relatively small, because with it the sturgeon voltage distance falls in critical areas. One considers at least one HF-transmitter in direct nearness with, that in the doubtful case approx. 1 watt of radiated power, and, nevertheless, no disturbances in the buddy-cable einekoppelt may become (is this why Graupner recently used optical fibre cable for the connection of both transmitters?).
The area of the permissible operation for our adapter lies between approx. 1 volt and 11 volts for the buddy-output signal.
As to the polarity of this signal we need to do not have to bother, this has already taken been taken into account for us by Michael in his brilliant program.

To whom this whole description means nothing or who does not know which part is the hot end in a soldering iron, he can let help in the building (and if necessary in the initial start-up) the circuit of somebody who knows electronics.

Needless to say that I can take no guarantee for the fact that the described circuit will work with every combination from remote control transmitter and PC. Simmilarly I cannot guarantee that, nothing gets broken. After Adam Riese can actually with neat construction (no short circuits, no connections exchanged) nothing pass, after Murphy again just EVERYTHING will happen and Murphy has got nothing, luckily, evidently from my attempts). Everone must realize that the described way of the connection of his remote control transmitter with the PC is not as original design and is not covered by any guarantee. Who does not want to take this risk, should make way on one of the circuits stated by Michael.

Harald Sattler, June, 1999

I have just received another remote control in my hand. A Robbe Starion, 4 channels, no extension possibilities, no buddy-socket:-((
However, this is my fathers the remote control and I want with him to learn to fly his electric sparrow this summer, I thought, there must be a way...

Done thinking, with the case opened, I see, this enclosure has a HF-module which can be removed without tools. The connecting pins can be easily checked (oscilliscope) on which Pin the digital signal lies, ground pins were also found quickly. The digital signal surprisingly corresponds to my needs, also 9 V of signal amplitude. I quickly equip the adapter plug for the Parallel port with resistance and zener-diode, a long enough, 2-pole cable in between, screen in Pins 2 and 3 of a 5-pole Wirewrap-plug, core of the cable in Pin 5, there is is done.

The diagram in addition looks as follows:

                        +---------+
   A )------------------| 680 Ohm |---------*--------------------( Pin 10
                        +---------+         |
                                            |
                                          -----
    Connector                                /                Parallel-
    between Digital                         /\    ZPD 4v7     Port on
    and HF-part in                         /  \               PC
    transmitter                           ------
                                            |
                                            |
   B )--------------------------------------*--------------------( Pin 18

The ring of the zener diode must point to the resistance.


Look in the opened, transmitter lying on its back :

    +-----------------------------------------------------------~
    | housing from inside ("front") 
    |                               connection pins to the HF-part 
    |                               +---------+
    |   ----------------------------|o o o o o|-       (here on the right is 
    |   ----------------------------------------        usually
    |    Digital board               1 2 3 4 5          HF-parts)
    |
    |
    ~
    ~

    A to Pin 5
    B to Pin 2 and / or Pin 3 (are connected on the board anyway) 

To the plug in the transmitter I have now applied a Wirewrap-connection. These plugs consist of square pins, approx. 0.8 mms thick which are mounted side by side into a plastic header and are lined up 2.54 mm appart. From the board 5 pins are nipped off shortened to approx. 12 mm (the pins are approx. 20 mm long originally, both measured from under the plastic header) and the cable is soldered above the plastic header. The cable can be led for the operation of the transmitter with FMS e.g., by the hole where at the crystal usually sits. The HF-part is disconnected anyway, so we do not need to consider disabling this.

Now quickly fix the settings for the Port address and Interrupt and off we go.

No problems:-))

And still more information:
I briefly had a Hitec Flash 5 remote control. This has a buddy-socket again and can be connected with the Robbe / Futaba Skysport 4 as a buddy-combination (for allocation of the Pins in the plugs see above). The information to the operation as an input device for FMS to the Skysport 4 applies 1:1 to the plug allocation the Flash 5.

Harald Sattler, July, 1999

Here is the arrangement of the connecting lead by use of Europe MPX sprint transmitter. (Would have to function with all MPX transmitters.)

Top view on socket in the transmitter:

1 = battery + 2 = + if turned on 3 = battery - 4 = signal 5 = if connected to 3, no HF radiation

Also:



Graupner FM 314 transmitters can also be used, but with a small extra circuit (Then also as a pupil's transmitter with MC 18/20/24). On the board in the transmitter there is a connector (3 Pins) in the middle below. There a GR-Servo cable is attached so that the orange connection points to the left with the open transmitter and the aerial pointing away. The lead can be made with components soldered to a 3.5mm stereo jack socket and with the zener diode in the Sub-D-plug.

Bernd Hagen, November, 1999

Connection of the remote control FM-SS PROFESSIONAL 7/14 in the Parallel port of the PC's for the operation with FMS:

Material:

• 1x resistor 750 OHMS > = 1/8 watt
• 1x zener-diode 4.7 volts > = 1/8 watt
• 1x plug 25-pole (male) for connection with the Parallel port
• 1x board plug 5-pole (female). To get the correct plug have taken I my HF-module to electronics-shops. This seems to be the most sensible approach.
• Approx. 2.5 millimeters of contact socket distance.
• 1x 2-pole cable approx. 2-3m long
• various: (solder, insulation...)

Unfortunately, FM-SS PROFESSIONAL 7/14 possesses neither a connection for a buddy cable nor a connection to the " Sendelosen testing ". In the manual I found where the HF-module connection is. (If I remember correctly, one could acquire for this remote control HF-modules for different frequency bands). Now, I see my module is fastened not only by the connection, but in addition with 2 screws.

This is how I have built it:
Open the rear remote control lid (not just the inset black plastic lid.)
The module HF is in the middle of the remote control board. Remove the HF module.
Now on the board a 5-pole connector (male) should become visible. (see picture 2). See diagram 1 and picture 2. Solder the two wire cable to the appropriate pins.
Take care the distance to the remote control lid is rather small. Therefore bend the high contact pin in the plug and whole well insulated.
At the connection, a Perspex piece is fitted (at least with me) just here of the connection in the lid, with could open or close, however, one could produce a short circuit.... (You know) the cable can be taken out easily via the plastic lids oprning of the lid.
Because the connection described above is a little insecure I have taken the cable for the Steckverbindung via the upper carrying handle of the remote control. Close lids:-).
Have accommodated the "circuit" in diagram 1 within the parallel plug.
Finished.
Two words more: this remote control has a field strength meter. Because with the HF-module removed nothing more is sent, the announcement should stop in the "computer entreprise" on zero. The described circuit functions still if the battery test stands for a long time in the red area.

Why a Revision of the Resistance Values?
My transmitter is fitted out with 9 NC cells. Particularly therefore it is advisable to increase the resistance of the suggested interface. To come to a safe current of < 10 mA, I have calculated a resistance of approx. 733 ohms. The next standard value is 750 ohms, 1/8 watt is sufficient. (resistance and zener-diode are meant here only of protecting the remote control or the transmitter in case of a false connection. However, here with the low price of perhaps 2 DM I would not really avoid using)
I have seen on the board with the Anschlusstelle battery / fernsteuerungsplatine which can be used the transmitter probably also with normal batteries. In this case one could use perhaps for security reasons still a bigger resistor...

 The diagram 1 looks as follows:

                        +---------+
   5 )------------------| 750 Ohm |---------*--------------------( Pin 10
                        +---------+         |
                                            |
                                          -----
    HF-connection-pin                        /                Parallel
    in the transmitter                      /\    ZD 4v7      Port on
                                           /  \               PC
                                          ------
                                            |
                                            |
   2 )--------------------------------------*--------------------( Pin 18



Picture 2: remote control from the back
                                   ------


                     |
                     |   --- aerial
                     |
      -------------------------------
      |                             |
      |                             |
      |     Hf-Modul-Anschluss      |
      |            ooooo            |
      |            12345            |
      | --------------------------- |
      | | various adjusters       | | about the adjusters sits 
      | --------------------------- | usually black 
      | |        battery          | | plastic lid
      -------------------------------
 

Explanation of the HF-Modul-Anschluss:
(Allocation investigates only by " Fairs in the operation without HF-module ")

• 1:? Aerial? (No direct(straight) passage to the aerial)
• 2: Batteries deficit
• 3:? Puzzle plus? (Seems to have no direct(straight) passage to the battery, in the operation, however, possibly like 4)
• 4: Batteries plus (max. Approx. 9 x 1.34V =12,06V)
• 5: Switch Time pulse (negatively. I.e. has according to condition of the Informations of signal connection to 2 or no connection)

Michael Boese, November, 1999

Because the transmitter of no buddy socket (mine, not, anyhow), there is no option but to open the transmitter to enable a connection with the printer Port of the PC.

Unfortunately, the output stage of the control module can not be connected directly with the printer Port. It is not able to produce the required Low-level TTL signal. An adaptation step must be interposed .

1. Cable connections go between control module and HF-module to protect the HF-output stage from damage by the operation without aerial and to reduce the power consumption.

2. We need to find the PPM-output signal (point A look at the circuit diagram) and ground in the control module. On my transmitter the output signal about transparent of four leads (black, red, purple, transparent) of the already mentioned cable connection. In order to be sure it is best to measure again with an oscilloscope.

3. Connect an Npn-transistor (BC548 e.g.) to point A (see circuit diagram). The exit is simply taken out as an open-Collector and is connected with the /ACK input (Pin 10) of the PC printer port. Ground is connected with Pin 18 of the printer port. As a load resistance the internal Pullup resistance of the printer Ports is enough so a level adaptation is thereby unnecessary.

Circuit diagram:

Because the hardware of the parallel interface of PC varies to PC strongly, problems with the Parallel port are often an obstacle. As an alternative FMS also supports a serial interface. Between a remote control and the serial interface one needs to use the following circuit.