rpellicciotti

Hi all,
I have been running a Kingtech K180G2 with Kingtech ECU and Kingtech telemetry unit in a jet with PowerBox Royal SRS. It works great and I get the ECU telemetry on my Spektrum DX18G2. I recently built a new jet. It has a K85G2, Kingtech ECU and Kingtech Telemetry module as well. This second airplane has a Spektrum Powersafe receiver, model AR12310T. This smaller plane has less room inside for stuff so we were trying to get a receiver with dual power and telemetry module all in one.

Bottom line on this plane is that the ECU telemetry doesn't work. I talked to Spektrum and they say the problem is that the receiver does not send servo voltage through until after it powers up and initializes the telemetry units. Until the ECU sees voltage on the servo line, it doesn't turn on therefore it is not recognized by the receiver. I googled around and I found some comments from folks that are running Xicoy ECU's that are having this problem also. The folks with Xicoy have mentioned that Xicoy has made a change to their ECU's in order to correct the problem. I am curious if there is a fix in the works from Kingtech on their telemetry unit?

I have a work around that is clumsy but takes care of the problem. If anyone is interested, let me know and I will detail it. Ideally, Kingtech will modify future telemetry units / ECUs in some way that will work with these new receivers.

Rick Pellicciotti
Avanti Jet.com

opjose

Please detail it.

I just installed an AR 20 channel with Kingtech Telemetry into a sport jet and ran across the same problem!

gooseF22

Powerbox put out some wiring instructions for hooking it up someplace.. I saw it but cant find it now..

rcflyguy_26

My Feedback: (8)

Seen 65.5mm dia
160mm long

rpellicciotti

Sorry to take a bit to respond, I am just back from Mississippi Afterburner where I also had a chance to discuss this with Barry from Kingtech. Here is the deal:

The new powersafe receivers do not supply power to the servos until after the receiver has initialized which includes starting up the internal telemetry unit. The Kingtech ECU does not power up or send signals to the telemetry unit until it sees a voltage from the receiver on the throttle channel. So, since the ecu/telemetry unit is not alive when the receiver/telemetry unit initializes, it never recognizes the engine telemetry.

Solution:
There are two ways to solve the problem. One is quick and dirty and the other requires a little custom wiring.

Quick and dirty: Unplug the throttle lead from the ECU and plug a servo "Y" connector in its place. On one leg of the "Y" plug in the lead coming from the throttle channel (that was previously plugged into the ECU). Leave the other leg of the "Y" open and accessible. When you get ready to start your airplane, make sure your ECU battery is plugged in, make sure your receiver batteries are connected but the receiver is "OFF". Now, plug an extra receiver battery (make sure it is the same voltage as your batteries you run on your powersafe receiver) into the open "Y" connection on the throttle port of the ECU. When you do this, the ECU should wake up and the Kingtech telemetry module should come alive. Now switch on your receiver and let it initialize. Since the ECU/Kingtech telemetry was already alive, it should be recognized by the receiver. You may have to auto-config your telemetry the first time you do it. Once your engine telemetry is showing up, unplug the extra battery from the "Y" and all should be well. Note you will have to plug in this extra battery each time you start up your airplane then unplug it when the receiver is initialized and running.

Custom wiring method: If you build some extensions between where your receiver batteries are located and where the receiver is, you can simply include a tap off of one end or the other of one extension. This tap would run through a normally open push button switch and on to the "Y" plugged into the ECU throttle channel. This would eliminate the extra battery. The power up sequence would be to depress the pushbutton, wait for the ECU/telemetry to power up, switch on the receiver, then release the push button.

I hope this helps. Doing it this way is working fine for us here at AvantiJet.com If you need additional info, send me a PM and I'll be glad to help.

Rick Pellicciotti
Avanti Jet.com

jlarson31

Sounds like the power up sequence on the RX side is the issue. Only change I can imagine KT making is somehow drawing power from either the ECU pack or the throttle lead for the ECU with the throttle lead as primary. That would essentially do the the same thing as your Y harness trick. It would take a little redesign on their part as the voltages of the ECU pack and radio system typically are not the same. Otherwise, Spektrum would have to change the firmware in their RX's to "see" telemetry systems after boot/power up of the RX. Or essentially "see" any peripheral device that turns on after the startup. I'm NOT an electrical engineer, so no idea how technically challenging any of this would be for the designers.

My iX12 with the same RX you are using, AR123010T and a K-85, let me set the Turbine option on the telemetry screen. I didn't have it set that way when I did my test runs so I have not seen live turbine data yet on my Tx screen(s). Have not gotten the Telemetry unit to switch from blinking blue light to green light. According to the brief pdf document KT published, blinking blue means the telemetry unit is receiving data from the ECU. Green means it is sending it to the radio system, or in our case, the radio is taking the data.

Thank you for your solution Rick! I've been struggling with this for a few days now. New to turbines and obviously the iX12 is still a "new" platform on the market. I'm a long time Apple guy so learning the Android OS has been a new adventure too. Also having to get use to searching the owners manual through the radio when I do more involved radio setups. I printed a copy of my manual, but it's faster to bring up the pdf on screen, search it and then tap the screen instructions which take me right to the correct spot in the Airware app.

Joe Larson

jlarson31

It worked! I tried it this morning. Thank you Rick!

markusvt

When powering up the ECU either via at RX/Aux or Y channel with the Throttle it reverse powers up the Tx. It does work this way but I'm slightly worried on the Tx circuitry. If no long term issues with the Tx then why not leave a wire full time to the Rx/Aux that you leave on the Tx battery, (balance port) and just hook it first and leave it hooked?

jlarson31

Don't want to forget to turn off the ECU and drain one of my flight packs.
I tested it with a regular switch in my shop. When I install it in the plane, I'm going to make up a lead with a normally open momentary push button.
I made a brief video on FB and actually had both switches on for about 15 to 20 seconds. If power back feed was an issue, my RX or battery would have gotten warm, smoked or just flat out quit.

markusvt

I really don't like the back powering the Tx............ No worries for me on draining the battery. I unplug the main flightpack power and balance plug at the same time.

rpellicciotti

I'm glad it worked for you. We have about 10 flights on the new airplane and it is working fine. Most of Spektrum's telemetry senors are "passive" and don't require power (temp, voltage, etc). Their way works fine with those. Anything that requires power will need a work around like this.

Rick

rpellicciotti

A picture is worth a thousand words, right? Here is the harness I built for a friend's PilotRC Viperjet with Kingtech power and Spektrum powersafe receiver. The EC3 plugs into one of the receiver's battery connectors. The RX battery plugs into the other side of the EC3. The switch is a Normally Open, DPST pushbutton that gets mounted near the receiver switch. The free end plugs into a "Y" (not shown) that is in the throttle input on the ECU. The other side of the "Y" is connected to the lead running to the throttle channel (port 1?) on the receiver.

We use a double pole switch and switch both the ground and the plus connection. That way, when the switch is open, the circuit is completely isolated, there is no possibility of a ground loop.

Rick Pellicciotti
[email protected]
Avanti Jet.com


Kingtech Telemetry fix for Spektrum Powersafe receivers

patrnflyr

My Feedback: (7)

I'm getting ready to try this again and a Spektrum rep is going to walk me through this. He said they've had zero issues with the Kingtech unit booting up. I'm going to use FaceTime with him and do it together and see if there's a new fix somewhere in their updates. It'll be a few weeks before I can link up with him due to being out of town. Any other ideas?

aaronforth

I installed a small diode to eliminate this issue. Only let's current flow one way

frenchracer

i had success with the Y connector solution but just last week I got to the field and my ECU was dead. Would power up but could not read the throttle channel anymore. Had to send to Kingtech for repair. The fix needs to come on the Spectrum side with more delay in their telemetry module so that the rx powers up and feeds the Kingtech telemetry unit power and then initialized its telemetry circuit

PC12DRVR

I am currently setting up an Ultra Flash with a K142 and KingTech telemetry module connected to a 20ch power safe and am having this issue.

Besides reverse powering the telemetry unit has there been a fix ? This is a brand new K142 so it seems as if KingTech and spektrum have not addressed this ?

One person mention there ECU died was this an isolated event what has been peoples success with the y harness method ?