RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

Demon Cortex Setup

Reply

Old 02-22-2019, 10:19 PM
  #1  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Demon Cortex Setup

Ok guys I have had this gyro sitting around here several years. I have zero experience and working knowledge of this unit. I have the printed instructions and quick start set of instructions. Infact I may have two different sets of instructions plus the quick start card. I am unclear on how to plug it all in and make it work correctly. I am going to put it my EFLITE T-28 initially so I can learn how to plug it in and so on. Access to the receiver and the gyro is very good. I made a platform to mount the gyro to and secured it in the airplane. I have not yet mounted the gyro however. for starters I thought I would get on channel set up and working. The airplane uses two servos for aileron plugged in with a 'y' connector. The elevator is a single servo. The rudder has one servo for rudder and one for nose wheel steering. connected to the rx with a 'Y" connector.

I find the instructions to be a bit lacking but maybe I just tired and or terminally not the brightest bulb. My first problem is I see that a "jumper" is required to plug into the last slot on the gyro near the"X" in cortex. Maybe I missed it but I cant find the jumper ( or is it part of the wire "loom" bundle) ? Is it one of the two connectors with red/white/black wires ? Or is a separate jumper like JR/Spektrum bind plug or .......... ???

So now lets say I want to make the roll axis stabilized...what do I plug and where do I plug it ? Remember my aileron setup uses two servos with a 'Y" connector so only channel on the rx is used on this particular airplane. Which single lead (single wire) to I plug in to the rx I assume in the aileron channel .

Once I get the ailerons working I will get the rudder and or rudder and nose wheel steering set up.

Then I will set up the elevator (single servo). Or maybe a better plan is just get the ailerons up and running.and nothing else and complete the entire setup and on off switching set up (step6) on page 6

Any and all help and suggestions will be appreciated. If all else fails I will take it to my local hobbyshop (JT Hobby) I know Joey knows how to set up a cortex. My pride would prefer to get it figured out without his aide however, I mean how hard can it be ??
turnnburn is offline  
Reply With Quote
Old 02-23-2019, 04:03 AM
  #2  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 3,873
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

...

Last edited by Bob_B; 02-23-2019 at 04:07 AM.
Bob_B is offline  
Reply With Quote
Old 02-23-2019, 05:44 AM
  #3  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

As far as I know this is Demon Cortex, not a "PRO" . I assume if it was the pro version it would say "PRO" on it somewhere ?
turnnburn is offline  
Reply With Quote
Old 02-23-2019, 06:00 AM
  #4  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 3,873
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default


Does it look like this
Bob_B is offline  
Reply With Quote
Old 02-23-2019, 06:01 AM
  #5  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 3,873
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default


Or this
Bob_B is offline  
Reply With Quote
Old 02-23-2019, 06:32 AM
  #6  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

The one in your second post is the one I have.
turnnburn is offline  
Reply With Quote
Old 02-23-2019, 06:33 AM
  #7  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

the second choice.
turnnburn is offline  
Reply With Quote
Old 02-23-2019, 07:29 AM
  #8  
Len Todd
 
Join Date: Jul 2012
Location: Baldwin, MI
Posts: 1,249
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Did you google for a video? Use "cortex demon setup video".
Len Todd is offline  
Reply With Quote
Old 02-23-2019, 07:53 AM
  #9  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

No I did not. I don't know why I didn't think of that. I will give that a try in an hour or two. I bet that will do the trick.

Thanks
turnnburn is offline  
Reply With Quote
Old 02-23-2019, 08:48 AM
  #10  
sirrom
My Feedback: (4)
 
Join Date: Dec 2001
Location: Sarasota, FL
Posts: 962
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by turnnburn View Post
No I did not. I don't know why I didn't think of that. I will give that a try in an hour or two. I bet that will do the trick.

Thanks
Try this video. It is the one I watched to help me learn how to setup mine. Its 3 parts and very comprehensive.


Patrick
sirrom is offline  
Reply With Quote
Old 02-23-2019, 05:43 PM
  #11  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I got it mostly figured out without a video. I tried watching two different videos but they weren't very well done. I gave up on them. I ran out of time before I figured out how to adjust the gain from the TX. otherwise I get it figured out I think. I will try watching this other video if I need to. Thanks for the help.
turnnburn is offline  
Reply With Quote
Old 02-24-2019, 06:11 AM
  #12  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I watched the video recommended above and it was certainly a better video than the others I had watched. I got it all figured out and working correctly now. Thanks again for the help.
turnnburn is offline  
Reply With Quote
Old 03-02-2019, 11:22 AM
  #13  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Ok, here is where I am at on this Cortex gyro currently. I have it installed my old foamy T-28 (the little one). I have it working correctly on the bench. In other words the controls all respond in opposition to a bank or nose low, nose high, and yaw.
I have it on a three postion switch on my TX. Center is off (solid red light) Up is hold mode (solid green light) down is solid yellow light, normal mode. I tried flying it a week or so ago and didn't feel like it was working in flight as I thought it should. I put airplane in a shallow bank (20 degrees or so) center the stick and expected the plane to level itself from both bank and nose down pitch due to loss of lift when banked. Instead it just held that attitude. It finally dawned on me this morning that I might have thought I was in normal flight mode when I was infact on HOLD mode. I got the instructions out and reread and sure enough that was exactly what was happening. I made the assumption that solid green light would be the "Normal" flight mode for an airplane but it is in fact the hold mode. The solid amber or yellow light indicates normal flight mode.
So armed with that I went back out to fly a short while ago. I put airplane in a left bank, centered the stick and it smoothly and somewhat slowly leveled the wings and nose.......just the way I thought it should. I did that again except pitched nose only way up and it returned to level flight. Nose down same thing. So far so good.

Then I tried a right bank and it did NOT return to level flight but rather just stayed in right wing low and nose low. Mind you it is still in normal mode at this point, 3 postion switch in low position which is normal mode. It is still responding correctly on the bench but it does appear to be way more sensitive when banked left vs to the right. It seems that it responds with more aileron throw or travel when banked left vs right and it seems like it might be slower to center the control surfaces when banked left vs right. But it is hard to say for sure just by watching with the naked eye vs seeing how it reacts in flight. What I know for sure is that it was not correctly (leveling the wings when bank right in flight). I tried increasing the sensitivity some but was not able to make another flight because the battery was to low to fly. I have it recharged and will go try again. with more control gain . The ailerons are on a "Y"" connector. could this be why ? Maybe I am only turning up the travel/sensitivity/gain in one direction ?

I turned up the gain way up , I don't think the y connection is a factor. With full gain I can see lots of control movement in both directions on all controls.

Last edited by turnnburn; 03-02-2019 at 11:30 AM.
turnnburn is offline  
Reply With Quote
Old 03-02-2019, 11:52 AM
  #14  
Len Todd
 
Join Date: Jul 2012
Location: Baldwin, MI
Posts: 1,249
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Are you thinking that if you release the Txer's controls the plane will level? That is not the way gyros work. Maybe you are thinking of HH's SAFE mode. There is even a difference between HH's SAFE and their gyro (AS3X) mode. Gyros will correct, for example, a shift caused by a wind. But if you put the stick in the down position the plane goes down and a the plane will continue to go down if you release the stick. It will not level a plane that has been going down or up. If you are in a bank, and you release the Ailes, the plane will not come out of the bank w/o you making the correction with the sticks. Gyros do not make those kind of corrections. The Cortex is NOT capable of SAFE type corrections.

You do not use heading hold on normal planes. It makes the planes hard to do normal turns. On 3D planes ... maybe use heading hold in a hover or torque roll. Heading hold is more typically used in Helis to keep the tail aligned with forward travel, etc.

To set the gain, I increase the gain until the surface I am adjusting starts to oscillate and back it off a hair until the oscillations stops. However, … Typically, real time adjustments simultaneously adjust the gain on all three surfaces, Which is a PITA. Unless you started with some fairly close settings on each surface, you have to go back to the Gyro's programming and individually adjust each surface a bit to get it close. Get each surface close and then the real time adjustments frequently work.
Len Todd is offline  
Reply With Quote
Old 03-02-2019, 01:08 PM
  #15  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Actually I initially was thinking that if I bank the plane the gyro would not level the wings once I remove the control input. But then when I flew it his morning and banked left it would slowly roll back to wings level but not to the right. I guess what is happening is a couple of things. I must not have it trimmed for level (non banked ) flight very well. it must have a slow right bank/roll with where the trims are currently set. The other factor may just be inherent stability of this particular plane. Mostly it must be just enough out of trim. Another factor is that both times I have flown since getting the gyro operating the air has been very smooth and stable. I wasn't seeing the gyro do anything because it wasn't getting upset by bumps or thermals. The other factor would be that I did most of the flying the first time out in hold mode and just a small amount of the time in NORMAL mode. Like I said above, Normal mode or rate mode or whatever they call it would be considered the normal mode for most aircraft operations and to me a green light made sense and was telling me I was in normal mode when I was in fact in hold mode. I think it helps. I don't have it set very sensitively.

So........bottom line is............everything is working as it should be I think. I need some bumpy air or a less stable plane or both so I can see the gyro doing its thing. I put it in this plane to get an understanding of how it all works before putting it in an aerobatic plane or a jet.

So now I have a new question. One of our local jet flyers is known for his length of the field rock solid knife edge flight. I have seen him do it with a number of different jets. I know he has cortex or some sort of gyro on board because I asked him if he did. My question is..... would he be using the normal flight mode or the "hold" mode ?

As you can probably tell while I have been flying rc for nearly 60 years and jets for about 17 or 18 years. I have very little gyro assisted flight experience. I have a simple gyro on yaw axis in my TF C-310 that is just about the extent of my gyro assisted flight. The 310 can be a little bit of a fish tailer at times, that's why I have it on there.

Last edited by turnnburn; 03-02-2019 at 01:09 PM. Reason: adding some text
turnnburn is offline  
Reply With Quote
Old 03-02-2019, 01:33 PM
  #16  
Len Todd
 
Join Date: Jul 2012
Location: Baldwin, MI
Posts: 1,249
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Knife edge flight might be a good time for heading hold. Again, that is a straight flight path. Heading hold is also sometimes used on the nose wheel when landing. But, that typically is another gyro in the landing gear controller (e.g. LG15).
Len Todd is offline  
Reply With Quote
Old 03-02-2019, 05:06 PM
  #17  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

That's kind of what I was thinking for the knife edge's. Do you think he selects the hold mode before establishing the knife edge or "on" as soon as he can upon establishing the knife edge attitude ?
turnnburn is offline  
Reply With Quote
Old 03-02-2019, 10:49 PM
  #18  
F1 Rocket
 
Join Date: Nov 2006
Location: Melbourne, FL
Posts: 397
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Hold mode is only intended for hovering a 3D type airplane. All other flying is typically done in the normal mode.

Danny
F1 Rocket is online now  
Reply With Quote
Old 03-03-2019, 06:09 AM
  #19  
turnnburn
Thread Starter
My Feedback: (49)
 
Join Date: Jul 2002
Location: Arlington, TX
Posts: 996
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Is there some reason why it wouldn't work for knife edge flight with a jet or ANY plane capable of knife edge flight ??
turnnburn is offline  
Reply With Quote
Old 03-03-2019, 07:10 AM
  #20  
Reever45
My Feedback: (16)
 
Join Date: May 2013
Location: Grand Junction, CO
Posts: 70
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

In my experience a well balanced and any rudder coupling mixed out you can do length of the field knife edge passes with no gyro even installed. Of course all airplanes/jets are not created equal so some are going to be easier to do that with in my opinion. The gyro would help with smoothing things out if windy/bumpy conditions,I have flown most of the gyros out there and they differ a bit. The Igyro 3E can be flown in hold because it leaves the rudder in a normal rate mode,so basically just have the ailerons and elevator in hold. Also the Spektrum AS3X/AS3000 you can turn on hold for ail/ele and rudder stays in rate mode, I’ve used the Cortex in hold messing around with hovering/torque rolls but didn’t use it for normal flight.

You could get lined up and turn hold on for a knife edge pass, but would still require an aircraft balanced and trimmed well and then not sure would hold that hands off without a super high gain.
Reever45 is offline  
Reply With Quote
Old 03-03-2019, 01:20 PM
  #21  
Len Todd
 
Join Date: Jul 2012
Location: Baldwin, MI
Posts: 1,249
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Bottom Line: Even with a gyro you still have to be able to fly the plane and the maneuvers you want the plane to do.
Len Todd is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service