Posts by cespedes


    I am working on a new setup using the iGyro SRS and it is all SBUS. In the manual it states that the max current for the unit is 10amps. I plan on using the 2 digital-output ports as serial connections for the model. Would the 10amps be the expected max for servo draw through the unit? I was planning on connecting battery power to each of the 2 RXs or to the iGyro directly. Another option would be to connect the battery power to a more central (passive) device, like a sbus terminal box to distribute the power to the servos. Is this more advisable? I would like to use PowerBUS to BUS adapters for this role, but they appear to only accept MPX for input. I would have to make a dual-JR to MPX cable to connect the iGyro SRS DIG-OUT ports to the Power BUS MPX input port. Would this be more optimal & suggested? I'm trying to keep the plane as light as possible, this means no battery backer to save weight. I plan on using the new Sensor Switch v3 for power.

    Thoughts - suggestions - comments?

    A separate question which I know belongs in the PowerBus section. I will post it there and here as it is related to the topic above. Can the servo ports on the Powerbus to BUS adapter be used for serial input? I have not tested it, but I believe it would not work as each adapter has an amplifier, and this function (I think) takes place on the signal coming in on the MPX input port. That said, would the signal come into the sbus system on a servo port without amplification? Or would it be blocked/ dropped?

    Thank you for the help and support.


    Hi Rudi,

    Thank you for your input. I've been powering my current BECs for years off of the RX batteries & never had any problems. I'm more concerned about the SS specifically requiring a battery, that is what I need to understand. On my jets I also use the RX battery to power my gear. There is always quite a bit of debate about whether that makes sense to do or not, but again, never any problems either. I understand an ignition is quite different from a couple motors for the gear, but the BECs I've used previously have an optically isolated circuit to prevent interference or noise from getting back to the RX.

    Regarding sbus, I use a Futaba TX and their initial implementation of sbus2 was reserved for sensors, with native sbus being used exclusively for servos. I may have missed some recent update to the use of sbus. Any help would be appreciated.


    Does the SparkSwitch Pro support native sbus for the throttle signal? I see PWM signal to the receiver, but I figured I'd ask anyway, just in case. In the manual I see sbus2 is supported for telemetry for temp and rpm sensors, etc... But it also references channel 12 being used, not sure of the use of the channel. Lastly, in my current setup I'm using the RX batteries to power the ignition, does the SparkSwitch require a separate battery or can you power it from the RX battery system? Thank you in advance for your help.

    Hi Richard,

    Thank you, this helps. The reason for my question is I need to find a place to pull power for electron retracts. I'm thinking of pulling it from the output of the last adapter in the daisy chain. It would be very convenient as I would eliminate a battery and the adapter is right next to the gear controller in the fuselage.

    There is very little draw, only a few amps when it is cycling or if the brakes are applied, and consumption is only about 200-500 mAh in a day of flying.

    Have you heard of anyone else doing this?

    Is this recommended or not recommended?

    I checked polarity and I've tested, it works pretty well. I simply used a PB PBUS jumper by clipping the signal wire.

    LMK your thoughts/advice.


    Hello Richard,

    I would like to request more information related to the PowerBUS servo short-circuit protection. I would like to know how it works in more detail. I'm trying to determine what happens after the adapter notices there is a short.

    Does it look for a certain number of amps? If so, figures?

    Does it turn the port back on?

    Does this only work on a servo port or does it also work on the adapter OUT port? For example, if there are two adapters connected together out port to in port, and there is a problem with the second adapter, will the first adapter disable the out port to protect the servo connections on the first adapter?

    Any documentation or details you could provide would be appreciated.


    Hi Richard,

    I'm positive the unit is running version 16, but I am now not 100% sure it's a .9 unit, now that you question it. I will confirm and let you know when I get back. In the interim, are you saying that when it exhibits this condition, it's actually an indication of the gyro failing to initialize? If so, why would it fail to do so? What are some causes or conditions which would trigger this? I'd like to ensure it isn't something I'm doing, or if there is a fix, I'd like to consider applying it.

    Regarding the second issue, The Royal's screen definitely showed the correct voltage and capacity. Are you suspecting a bad signal or faulty teleconverter? I did look at the telemetry signal strength link between the rx and (looks like a cell phone signal indicator) the 18MZ. It showed high bars, plus the rx voltage which is provided natively by the R7003SB never changed or fluctuated. Only the volts and capacity for batt1 and batt2.

    Last issue, I can say with almost 100% certainty that I do not unplug my batteries while the unit is still powered-on, in fact, I would cringe if I saw someone do that. Is it possible there is something buggy related to the automatic power-on process?

    As always, thank you for your great support and help. I will get back to you with confirmation of 16.9 as soon as possible. If you could help me shed more light in the interim, I would greatly appreciate it.




    This past weekend I experienced a situation where I turned-on my radio (18mz) and then the plane, Royal SRS. The issue is that none of the servos would respond to commands from the radio, the screen on the SRS looked fine. I turned the plane off and on and the servos all worked fine. I ultimately flew the plane w/out issue.

    Today, I was preparing to fly the first flight of the day and my battery alerts (telemetry) began to go off. For example, it would read the correct volts on the screen of the Royal but on the telemetry screen on the radio it would go to zero for both volts and capacity for a second then revert to match the Royal's screen, and my alerts would trigger. It kept doing this until I unplugged the batteries from the Royal. I first tried to turn the plane off and on, I then tried to turn the plane and radio off and the condition remained. Once I unplugged the batteries from the Royal & reconnected, all worked fine.

    Lastly, I noticed one final odd condition recently. Not today or this week, but sometimes when I plug in a fresh battery the Royal it will automatically power on, it does not always do it though. I had planned on mentioning it before but I had forgotten until I was writing this post.

    I hope you can provide some insight on what is going on.




    I'm finalizing a new install and have been adding speech alerts for various telemetry readings. I would like to know if any of you have a good baseline on min/max when it comes to the following?

    - Number of Fades, RX1 and RX2

    - Number of Lost Frames

    I used to have a model with dual 7008SB RXs which would have a couple dozen fades and lost frames in a flight. I kept an eye on it and it never translated into a fail-safe. I also asked around and, at the time, I was advised that some "small" incremental numbers were not all that out of the ordinary. What do you think, would more than 1 and less than 100 be a good starting point or am I way off?

    Looking forward to your feedback.


    ok, that is what I figured as it is all working perfectly. Regarding voltage, I should be ok as I set 7.4v for both Bus A and Bus B.

    One more question, in order to make the plane 100% PBUS I had to obviously connect the turbine ECU throttle channel to a PBUS to PWM adapter. It seems to be working just fine, do you see an issue with that? A friend is worried as it's the turbine channel and suggested I connect it directly to the rx. I figured a channel is a channel and it should make no difference if it's the turbine throttle or a electronic air valve, as it's simply mapping the signal to a SBUS channel #. The way I have it I have rx redundancy.

    Just looking for peace of mind, thanks in advance.


    Hello Richard,

    New install using a Royal and 100% PBUS. In the Output mapping menu I mapped channels to ports in sequence. For example, channel 1=port a, channel 2=port b, channel 3=port c, etc... All seems to be working perfectly. My doubt is based on the mapping between physical ports which correspond to BUS A and BUS B and the 2 physical PBUS ports which also correspond to BUS A and BUS B. Some of my BUS A ports like L or M, N are physically connected to PBUS port B although on the unit they're part of BUS A.

    Does the output port mapping matter when only using the PBUS ports? Or is it dynamic based on the SBUS channel being recognized on the physical PBUS port? It doesn't seem to, and you only have 6 BUS B output ports to use, so it's impossible to evenly map/split channels between the two buses one for one. I tried and was unable to map them as I have more than 6 SBUS channels connected to the BUS B PBUS port. I hope my question makes sense, it's late here. LMK.



    I know the Gemini II has an on-board mag sensor and includes a button switch. My question is can you use a mag sensor connected to it as well for on/off function? I already have a Mag Sensor installed in the plane, I am removing a PB battery backer and I'm switching to the Gemini instead. It would help me keep the Mag Sensor in the current location and make it easy to simply add the Gemini. Thanks in advance.

    Hi Jake,

    wow, you and I are on the same page pal. Take a look at the pics, I picked some up this afternoon. I also picked up the spark plug protector, I cut it open and used it as a heat shield (blanket) and taped it all in place with the tape. I feel pretty good about it, thanks for the help.

    Hi Richard,

    I'm building a Pirotti Rebel and I intend to use PBUS throughout, and I would like to install a PowerBus to Bus adapter in the tail. There is space in the tail but it's limited to above or below the pipe, there is also some small space on the side of the pipe but it's tighter. The most space is above the pipe but I'm afraid of heat rising. My question is related to the adapter, how susceptible is it to heat?

    I assume the adapter is a passive device unlike the PWM to BUS adapter. Have you seen others do the same?

    I've included a picture of the adapter on a small cage on the top of the pipe (plane is inverted). The intent would be to secure the adapter to the top of the cage (other side of wood), so the wood would be between the pipe and the adapter, and I would use aluminum tape to try and insulate some of the heat away. Would this be acceptable from your point of view?