Bob_B

My Feedback: (11)

Youll want to use the gyro menu and assign it to your flap switch. Make sure you select "Normal" for each setting to be in bank 1, rate mode, "AVCS" selects bank 2, hold mode. Set your values to 0, 20, 40 percent to start.

Jetkopter

My Feedback: (1)

Last week I updated the cortex in my kingcat from version 12 to version 16 software, flew the plane this past weekend and the model has a really noticeable change in response to the ailerons. I fly rate mode only and bank 2 is set up with more gain for landing. Normal high speed flight is fine but the minute I touch the ailerons the plane becomes really sensitive around the roll axis. I didn't touch the stick priority or the latching and I left the gains set to what ever they where before the software update. I could go back a re teach the gyro and set it all back to factory setting but before I do that I want to see if any one else has had this experience. Thanks in advance.

F1 Rocket

Simply updating the FW should not have this dramatic effect. Each FW update has altered the feel a bit. You have gone 4 sets in one shot so its expected you would feel a difference but again, not this dramatic. I suggest you take a careful look at at the actual gain settings you are using and make sure you are flying in the bank you are expecting to fly in. If everything looks OK then reprogram the Cortex making sure the TX is set to high rates when you do it. Give me a call if you have any questions.

407-687-3126

Jetkopter

My Feedback: (1)

Thanks Danny

JJ4x4

I have a extra 300 that uses 3 servos per wing for ailerons 2 elevator servos and 2 rudder servos that's 10 channels. How would I hook up cortex after smart fly board?

siclick33

I am not very familiar with Smart-Fly products (although I have used their Smart Reg) but is there any reason you can't put the Cortex between the RX and the Smart-Fly Board?

JJ4x4

something about voltage from smart fly board not enough to power cortex.

siclick33

What Smart Fly board are you using?

The only limitation I can see on some Smart Fly units is that you can't plug servos into the Rx as the Rx voltage regulator is limited to 1amp. However 1 Amp should be way more than enough to power both the Rx and Cortex. As long as the servos are still supplied power by the Smart Fly's servo regulator, and not plugged into the Rx or the Cortex, then I think that would be ok (in fact I think it would be the best way to do it).

However, I would ask Smart-Fly for their advice to be sure.

JJ4x4

yes to me it seems the easiest way to do it but noticed others on this fourum used cortex after smart fly board between servos and smart fly board. So it really confused me.

rcjets_63

My Feedback: (4)

I respectfully disagree.

I fly my jet in 3-axis (roll, pitch, yaw) heading hold on take off and landing. And I fly it in 2-axis (roll, pitch) heading hold in normal flight (rudder in normal mode) but will switch to 3-axis HH in flight for some maneuvers (e.g. slow roll).

I can agree with that. It did take some getting used to and I had to hit the off switch a few times when I was learning.

Let's just examine the use of heading hold on the roll axis. Jets have some positive stability in roll (the airplane has a tendency to level the wings without any roll control input) from any dihedral and from the sweep back angle of the wing. The amount of roll stability will vary from airplane to airplane but it's always there and we get used to it and account for it automatically when we are flying.

Consider that you are flying a plane (jet or otherwise) and are on the base leg making a right turn upwind to do a pass over the runway. If the plane is steeply banked you will have to input some left roll so that the wings are level just as the plane matches the runway heading. However, if you were doing a long turn without a lot of bank angle, it may not be necessary to input any left roll as the plane's stability will slowly level the wings. All planes you've ever flown have reacted that way (though in varying amounts) and you've just gotten used to it.

Now, along comes heading hold and, with a flip of a switch, the positive stability is nulled and the roll angle will be held...no slow/automatic leveling (same thing on pitch axis and yaw axis if you've selected HH on them). Your model performs differently (and different from anything you have previously flown).

Of course it feels weird at first, but eventually you get the hang of it.

Regards,

Jim

JJ4x4

just called smart fly they only recommend cortex to be installed before smart fly board not after. Question solved thank you.

JJ4x4

called smart fly and they only recommend cortex to be installed before smart fly board not after. Prob solved. Thank you.

roydefiant

I bought a used jet with a cortex installed, has not been flown for 2 years, trying to grade the firmware from my PC.

Downloaded the 3.12 software to my computer. Downloaded the firmware 16 for the cortex demon. The demon screen right lower corner says USB connected and main screen says power up device and download to device will take 1 minute. Am I supposed to plug in a battery to the gyro? Seems like not recognizing my device (gyro)

Thanks

Roy

BarracudaHockey

My Feedback: (11)

yes the gyro needs rx power

rcjets_63

My Feedback: (4)

sHi Roy,

Yep, put the USB connection in the "Jumper" port and plug a battery into another port (such a "A"). The polarity of the ports is signal line closest to the demon logo on the top of the Cortex, negative farthest away from the demon, and positive in the middle.

Jim

roydefiant

Thanks guys, plugged a battery into gyro and download successful. They should tell you that in manual or web page

Roy

roydefiant

So this question is related to setup with a JETI DS-16 and demon cortex. I have assigned the gyro to a 3 way switch. One position is gains at 0 (gyro off), Second position gain at -30 and third position gain at -40. The question is what do I do in servo setup (on channel 14) with max positive and max negative? I assume I leave those at the default -100 and +100?

Thanks

bluelevel

My Feedback: (39)

You need to leave the max travel at 100, otherwise you'll reduce the gain further. Have you already flown the plane with 30% and even 40% gain? Sounds like very high gain settings to me.

Thomas

roydefiant

The jet is a MB339 with 2.7 meter wingspan. I have 6 flights on it so far. Just hooked up the demon gyro for the first time. Think maybe 20% and 30% for position 2 and 3 respectively for first flights?

Thanks

Roy

bluelevel

My Feedback: (39)

Roy,

my sport jets usually end up at 25% gain on elevator & aileron and 20% on rudder. So starting with 20% and 30% sounds fine to me. I also suggest to reduce the expo by about 10-15% whenever the gyro is on, otherwise you'll have a slightly "mushy" control feeling. Another way to tackle this would be through the Cortex software, here you can increase the "stick priority" slightly once you've found the right gain setting.

Thomas

roydefiant

Thanks Thomas, so next question is how do I link the gyro switch to the expo throw so I can keep what I have with gyro off but have it turned down to 10-15% when gyro on position 2 or 3?

Thanks

Roy

bluelevel

My Feedback: (39)

Roy,

I do not know what kind of radio you use, but all modern computer radios support flight modes or dual rates. Simply create 2 different flight modes (gyro on and gyro off) and assign the same switch that switches the gyro on and off. Within these flight modes you should be able to set the expo independently from each other. If you don't want to use flight modes, you can achieve the same within the dual rates menu of your radio by assigning the gyro on/off switch.

Thomas

rcjets_63

My Feedback: (4)

Hi Roy,

You can leave the max positive and max negative setting at -100 and put the max positive at 0.

Incidentally, I'm not sure how sure you are about your -30 and -40 values. Are these guesses or did you flight test them? I initially set the gyro up to operate on the rotary knob where off (0% is all the way to the left, and 100% is all the way to the right). Turn on Sound of Prop Controls to read out the value. Adjust servo setup to give you 0% to -100%. Then I test fly (take off with 0%) and do some high speed passes turning up the gain with each pass until I get the value which works best. Then I drop the flaps to landing and do some slow speed passes turning up the gain a bit until I get the response I like and then I land (with the slow speed gain value). All you have to do is remember the high speed value from earlier in the flight (which isn't all that hard). Then I setup the flap switch to drive the gain, use the high speed value for flaps up, the low speed value for landing flaps, and the mid-point for takeoff.

Regards,

Jim

gooseF22

+1
but I tie my gains to Flight modes and don't use a switch once I know my base values.

Ken LaPointe

My Feedback: (4)

Does the Cortex care where in the plane its located? Is closer to the CG better than stuck out in the nose?

I would think closer to the axis of rotation would provide the best performance but there doesn't appear to be any guidance that you need to place it near the CG.

Is there a best place for the Cortex ?

thanks in advance,

Ken