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Dual elevator servos?

Old 01-03-2015, 06:47 PM
  #26  
abufletcher
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Personally, I'm not a fan of touch screens. (And no, I don't own a smart phone...or any cell phone for that matter.) Up to now, the RDS8000 has been as "complicated" as any radio I had ever hoped to use. Which is to say I hoped never to have to use anything more complicated. But the prospect of flying bigger and more complex models (though I''ll never be flying anything other than WWI other than for practice) makes a few "fancier" features like throttle curves appealing.
Old 01-03-2015, 06:52 PM
  #27  
gravityking
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Start by plugging one servo into channel 1 and the other channel 7.
turn on radio and hit end button several times to get home. Push left arrow once to highlight ETC menu at top right of screen.
Push the down button until the screen reads "BASIC". Does it show ON or OFF?

Last edited by gravityking; 01-03-2015 at 06:58 PM.
Old 01-03-2015, 07:02 PM
  #28  
Johnny_Zero
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Originally Posted by wnewbury
There is a theory that 2 elevator servos gives you a slight safety benefit due to the redundancy. That if one elevator servo screws up, you have a chance of being able to save the airplane. Like if the ailerons go, you still have the rudder. I am NOT volunteering to test the theory.

I have had this happen on a Goldberg Ultimate 1.20 Bipe and a TF 1/7 scale Mustang. Saved both planes when otherwise they would have been lost. Do a YouTube search on dual elevator servos and the RSD 8000. You Tube and Google are your best friends many time when you don't know how to do something.

Maybe this will help.

http://rcheliguy.com/global/airtroni...ra%20Stick.pdf
Old 01-03-2015, 07:10 PM
  #29  
gravityking
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Not what your looking for. I can walk you through this in 10 minutes if you wire up the servos like I mentioned above.
Old 01-03-2015, 07:14 PM
  #30  
speedracerntrixie
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Agreed, my race airplanes are set up with dual elevator servos under the wing and independant pushrods. The secon race of this season I was clipped in the tail by another airplane. The impact jammed my right elevator about 1/4" in the up position. Being that the other elevator half was untouched I was able to land. Video is on YouTube, search " Was it a midair at the T-34 race "
Old 01-03-2015, 07:39 PM
  #31  
vertical grimmace
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Originally Posted by abufletcher
I've never had a model with a servo for each elevator half (in the tail). So how do I do the radio setup for this? In my hazy thinking I imagined I could just connect the two with a Y-harness and then a long lead to the Rx. But the Y-harness reverses one servo. Or is there some other type of Y-harness needed? Or is the additional elevator servo also connected to the Rx, and if so how?

I'm using an 8-ch Airtronics RDS8000.
The Y harness does not reverse the servo. You just have to make sure that you put the horn on the right side of the servo. I have at least 3 large scale models with dual elevator servos on a Y. IT mainly depends on how much capability you have with your radio and RX ports. It can be nice to mix them electronically.
Old 01-03-2015, 07:49 PM
  #32  
DISCUS54
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Abu, a picture is worth a thousand words...have you looked at any the videos on the you tube site. I don't use Airtronics but surely you must have a couple of programmable mixes in there...where you can plug the right elevator into the elevator and the left elevator into aux 1 or 2 and then slave the aux channel to the master elevator. You do the ailerons in the same manner, except IF you have two aileron servos per wing then you are going to need either a matchbox and a Y harness or perhaps one of the buses from Smartfly or Powerbox to match then up. Ideally, you are not going to need a big adjustment if you can keep the geometry symmetrical on the linkages and mechanically adjust the errors out before you start in with the radio adjustments. When matching up the two elevator halves...use a rigid tube (CF works well) mounted to each elevator top snugly with painters tape and the ends extending out behind the rudder on the centerline. The tube ends should nearly touch each other...this will allow you to visually see and adjust the variation out of the entire travel and it should be fairly close if you start with just the sub and end points.
Old 01-03-2015, 08:02 PM
  #33  
cloudancer03
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I haven't used air tropics in years but the simplest way is Y harness with a servo reverser.or use a match box.a few bucks more but then how much have got invested in your prize bird.i always avoided twin elevators as it was truly a pain programing.to my suprise when I transitioned to a new futaba 8 radio I had to set up split elevators for my 30 cc edge and when I made a few simple connections and touched a couple button I was so amazed it just workeno zeroing out no mixing.what a great systemd
Old 01-03-2015, 08:08 PM
  #34  
vertical grimmace
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The function in my radio is "Ailevator".

This is the same as the dual battery issue. You can make this as simple or complicated as you wish. If you maintain symmetrical geometry with your horns and linkages, and you have your horns on the right side of the servo, a Y harness will suffice.

Remember the days when we did not have servo reversing? It can be done without all of the xtra boxes and such.
Old 01-03-2015, 08:21 PM
  #35  
speedracerntrixie
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The problem is not the linkage geometry. I have been doing servo matching either through the TX or matching devices in IMAC airplanes for over 13 years. The issue is that no two servos have exactly the same sweep. They really should but they don't. I'm very particular on setups and what makes my head explode may not be a big deal to others.
Old 01-03-2015, 08:29 PM
  #36  
vertical grimmace
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Originally Posted by speedracerntrixie
The problem is not the linkage geometry. I have been doing servo matching either through the TX or matching devices in IMAC airplanes for over 13 years. The issue is that no two servos have exactly the same sweep. They really should but they don't. I'm very particular on setups and what makes my head explode may not be a big deal to others.
I am going to venture a guess that this is not a competition IMAC plane. It really depends on what your needs are, based upon your your particular application. Big difference between high performance competition models and sport aircraft. In fact on my scale WW1 models, they are so dirty, they never really trim out. You have to just fly them all the time.
Old 01-03-2015, 11:39 PM
  #37  
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SImple solution for me is to buy Digital servo's that can be programmed, then just reverse one servo via programming and it will run on a Y lead. Yes you can buy powerboxes, I own a couple, but I still reverse servos via programming if I need to and I can.

Last edited by mackeyjones; 01-03-2015 at 11:42 PM.
Old 01-04-2015, 02:16 AM
  #38  
abufletcher
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Originally Posted by gravityking
Not what your looking for. I can walk you through this in 10 minutes if you wire up the servos like I mentioned above.
Now that I've read p.62 of the manual (Dual Elevator Mixing) it should be no problem. Now, I guess I can ask about the dual (one for each wing half) aileron servos. Again, I had just simple-mindedly been thinking of using a Y-harness as on smaller models. But now it seems to make sense (for the same reasons) to use programming to handle this. While there doesn't appear to be anything called "Dual Aileron Mixing" I should be able to do the same thing with the Aileron-differential setup (with one servo plugged into ch2 and the other plugged into ch6).

One problem arises, however. As was discussed in another thread, I was planning to use a simple dual battery/dual switch setup for power. Going the KISS route mean plugging the two power sources into two Rx slots. So with two slots for the elevator, two slots for the ailerons, there's just not enough slots on a 8ch Rx for everything. Something has to go.
Old 01-04-2015, 05:39 AM
  #39  
advanceandy
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nothing has to go that is where a y harness comes in handy

Last edited by advanceandy; 01-04-2015 at 05:42 AM.
Old 01-04-2015, 05:42 AM
  #40  
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Just put one of the servos on a Y lead with the 2nd battery that way it will supply power to the Rx through the Y lead.
Old 01-04-2015, 06:11 AM
  #41  
R/C Art
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Originally Posted by FSki
Just put one of the servos on a Y lead with the 2nd battery that way it will supply power to the Rx through the Y lead.
FSki is right, Don. It's as easy peasy as it gets!
Old 01-04-2015, 06:24 AM
  #42  
abufletcher
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I'm glad you guys are around to untangle my brain! Just for the symmetry of the thing, would there be anything wrong (or pointless) about running both batteries (and their switches) through a Y-harness into the usual one power slot?

It's turning my brain inside out to think of plugging an aileron into one side of a Y-harness and a battery into the other.

Last edited by abufletcher; 01-04-2015 at 06:27 AM.
Old 01-04-2015, 08:08 AM
  #43  
advanceandy
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Originally Posted by abufletcher
I'm glad you guys are around to untangle my brain! Just for the symmetry of the thing, would there be anything wrong (or pointless) about running both batteries (and their switches) through a Y-harness into the usual one power slot?

.
yes, going that rout you would only be able to provide 1/2 of the current (amps) limited by the conductor size, by using a y you can provide twice the current to your servos
Old 01-04-2015, 08:27 AM
  #44  
gravityking
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Yes, Y the batteries, use 1 & 7 for your elevators. If you made your way into the deluxe menu then you have already turned off BASIC. Look for a "D-EL" mix. It will show "INH" by default so hit the "YES" button once to change it to "ACT". That's it!

if your lucky the elevators will work as needed. If they go opposite each other or backwards from the stick, go into servo reversing and change 1 or 7 or both.
Old 01-04-2015, 08:37 AM
  #45  
RBACONS
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Bear in mind, if you plug 2 batteries into one receiver, whether directly or through a Y-harness, you will likely not be able to charge the batteries through the switch(s) external charge port but will need to unplug the batteries to charge them.
Old 01-04-2015, 08:44 AM
  #46  
vertical grimmace
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Don, now you are realizing the trouble you get into with so many servos, and trying to mix them all together. You run out of slots in your RX to receive all of these servos. This is one of the reasons why power expanders are used, as they facilitate more servos with more servo ports. As, again, with IMAC style aircraft, which seem to be the type of aircraft that have really driven these technologies.

I use Y harnesses on my batteries on most of my planes to free up these slots.

Just an FYI, I currently am flying a Great Planes 50cc sized Ultimate biplane. It has 4 aileron servos. All of them are on Y harnesses and it is working fine.

There are some little things you have to deal with when electronically mixing, that you are going to run into. Like getting the slaved servo to move with the trim switch. They have to be linked properly, or sometimes only the master will move with trim. All of this depends on your TX.

It is good to get experience with this stuff though, so play around with what set up works best for you. You can always go back and change it to a different configuration later if do not like it.
Old 01-04-2015, 09:11 AM
  #47  
flycatch
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http://rcheliguy.com/global/airtroni...0%20Manual.pdf Go to page #62 for dual elevator hook-up.
Old 01-04-2015, 10:17 AM
  #48  
gravityking
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He's already read page 62 and correct me if I'm wrong but seems overwhelmed by the "stereo instruction" layout of the manual. Also if you use the D-EL mix there is no slaving or individual trimming or issues related to slaving the second elevator half. It's a " boxed" mix and requires nothing other than reversing one to match the other. It's just not as complicated as being made out. 3 steps, done, in the air.

Also the batteries can be double Y'd along with a servo so no receiver port needs to be used exclusively for the batteries.

Last edited by gravityking; 01-04-2015 at 10:35 AM.
Old 01-04-2015, 11:00 AM
  #49  
4ptroll
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Here ya go....try this device from smart fly. Works great and better than a reversing Y cable.

http://smart-fly.com/index.php?route...&product_id=62

Originally Posted by abufletcher
I've never had a model with a servo for each elevator half (in the tail). So how do I do the radio setup for this? In my hazy thinking I imagined I could just connect the two with a Y-harness and then a long lead to the Rx. But the Y-harness reverses one servo. Or is there some other type of Y-harness needed? Or is the additional elevator servo also connected to the Rx, and if so how?

I'm using an 8-ch Airtronics RDS8000.
Old 01-04-2015, 01:47 PM
  #50  
BarracudaHockey
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Excellent product, but why add that bit of complexity and cost when his radio already does it for free?

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