Sparkswitch Pro / Mercury SRS / DA120

  • Hi Team,

    I would like to connect my Sparkswitch Pro, DA120 ignition, PowerPack 2.5x2 Pro, Mercury SRS, RPM pick up all together for a Futaba system.

    So if I understand from the forum and manual, please confirm if ok:

    - the ignition wire and the rpm pick up wire go to the ignition socket with a Y lead. I set 5.9V outpout for the DA120 ignition module.

    - the Power pack wire goes to the battery socket. Do you recommend to add a switch instead of plugging / unplugging ? Any other recommendation like "safety distance" ?

    - A mercury srs socket (any ?) is connected to the Sparkswitch receiver socket ?

    - the Futaba receiver SBUS socket is connected to the Sparkswitch Telemetry and data socket, in order to read the RPM. If I add the temp sensor, I will also read the temp.

    Is this correct ?


  • Hello,

    1. the ignition wire and RPM pickup are connected with Y-harness to the ignition output of the SparkSwitch: Ignitions without Tacho output - Zündungen ohne Tachoausgang
    2. You don´t have to connect/disconnect the battery: if the SparkSwitch is off - it takes only some µA from the battery.
    3. The Tele socket from SparkSwitch is connected direct to the S.BUS2 input from the receiver. For servo date + telemetry. Einstellen des SparkSwitch PRO auf Futaba
    4. see 3.
  • There must be a connection to the receiver (or to Your Mercury) for the switch-function "ignition on/off". This connection is independent from telemetric data. Just like a servo-connection.


  • Ok, a slight confusion to clear

    you said:

    But you need a teleconverter from the Mercury to the receiver S:BUS2 for telemetry

    i thought that having the Sparkswitch connected directly to the sbus port of the futaba receiver was actually passing the data.

    For what purpose I need a teleconverter between the mercury and sbus2 receiver ?

    because I have 2 futaba receivers, connected to the mercury via the sbus ports so I have not port left or I am missing something?


  • Hi Richard !

    So I did the connections as suggested. I used a Y wire to be able to have the Sparkswitch Pro "Tele" and Mercury "RX" wires to my Futaba SBUS2 port.

    I cannot run the engine yet so I cannot tell about the rpm, so I plugged the Temp sensor to test, and yes it works.

    However I cannot tell if I am turning the ignition output on/off as the LED never turns red.

    I set up the Sparkswitch in the PB Mobile Terminal, to Sbus and default channel 12. This might be the cause, since I use 2 RX Futaba R7003SB with only 4 ports (3 ports + 1 SBUS port), I am told that I have only 8 channels so if the Spark is on channel 12, it wont work. Is this correct ?

  • Could you please clarify:

    Take care your channels starts in the middle, not endpoint

    I assigned a knob switch (RD) to channel 12 on my Futaba T18SZ to prevent wrong manipulation.

    No change to default settings for this switch.

  • Ok so I realized a very little click coming from ignition when I was turning my knob switch. I took a spare led light and plugged it the exact same way to the Sparkswitch, and the light came ! So the led I got with this Sparkswitch has simply inverted wires, that s all, I just plugged it the other way....

  • Hi Richard,

    I realized that my Mercury RX ports were connected to my 2 RX (7003SB) SBUS2 port. However it says to connect to the PORT 1 (SBUS).

    - is there a problem with this ? what can happen ? my controls work on the ground.

    I actually did an engine run, ignition works but no RPM reading on T18SZ from the RPM Pickup. Ignition and Mercury port are on Y lead on SBUS2. Maybe if I now allocate SBUS port to RX mercury and SBUS2 to Sparkswitch Pro (no more Y lead) it could work...?



  • Hi Richard

    I would need help to make sure I got the temperature and rpm reading from the sparkswitchpro and my teleconverter set up is correct.

    1) i have Curr 1678 on slot 1 and seems ok, with mercury I will only get the voltage but no current and capacity ?

    See pic

    Do I need to “read” the other sensors like temp (although it is just a simple wire) and the RPM pick up ?

    2) then I want to put temp on slot 4 but no reading. The sensor is plugged to the Temp slot on the sparkswitch.
    see pic

    How is called the RPM pick up sensor ? Just rpm ?

    3) for my teleconverter I used a y lead to rx sbus2 for teleconverter and Sparkswitch (same rx).
    First attempt with Y lead from PB and nothing, cannot turn on ignition. The I changed to another Y lead and it is working + data. All set to RX1.
    i start again and no more data...

    i moved everything to RX2 and it worked. I turned off/on several times, and still works. Data and can turn on ignition.
    why can be the cause ?

  • Hello,

    1. mercury doesn´t have capacity and current output

    2. There are two types of temperature sensor available in the Futaba menu. Just try the other one.

    3. Only one RX can forward telemetry at Futaba, so I guess it was 50:50 - the wrong one.