millerhill

My Feedback: (19)

I'm building an EF Yak 74 and it's my first big (well...big for me) plane with dual elevator servos. I'm using a Futaba 7ch Faast TX. It has an "Ailevator" setting and plugging the two servos into channel one and two respectively doesn't work even when I set the aileron controls to zero and elevator 1 to 100% and 2 to -100% as it says in the instructions. When set up this way one of the elevators still responds to the aileron control stick. What am I doing wrong?

Steve

victorzamora

You plug them up to different channels....I think channels 2 and 7. I could be wrong.

Flyfalcons

You plugged them into the wrong channel slots.

JoeAirPort

My Feedback: (41)

My 9C has ailerons on 1 and 6 for flaperons and 2 and 8 for the ailavators. The 7C 2.4G manual doesn't say what channels the ailavator uses.

Maybe this is it too. You have to dial the aileron part of the mix to 0%:

"Once AILEVATOR is activated, unless you zero out the aileron figures (see below), any time you move your ailerons or any
programming moves your ailerons (ie. RUDDER-AILERON mixing), the radio automatically commands both elevator servos
to also operate as ailerons. To deactivate this action, simply set the 2 aileron travel settings to 0 in the AILEVATOR function.
This way the elevators will work only as elevators."

http://manuals.hobbico.com/fut/7c-2_4ghz-manual.pdf

millerhill

My Feedback: (19)

I did that and there was no effect at all. One elevator half works normally and the other elevator half responds only to the aileron. I saw some other mention about putting one servo on ch 2 and then the other on 7 with a "p mix". I followed the directions in the manual and they don't work.

Steve

flaminheli

You can set them up on 2 and 6 on a p mix. The channel six is controlled by the dial switch. But they will both work together with the elevator function. I have set up several planes this way and I currently have my 30% yak set up that way.

altavillan

My Feedback: (1)

Go back to ailevator page and set activate where you see inh. Put the highlite there and rotate the dial to activate/inhibit function.. The radio has a function page that tells you what channel is what function. Channels are assigned per groopings. Use function page to find the built in channel assignments for the 7c 2.4. The new Futaba groopings and channel assignments are completely different from any previous radio. You also have to select wing and tail type or is that with the 12z I forget. No I think you have to select an airplane type and wing to tell the radio how many aileron servos.

millerhill

My Feedback: (19)

I did go through the instructions in the manual to the tee, but like I mentioned, the manual doesn't give any specifics about what channel/s to use. I'll give it another go, but I'm not optimistic given what others are saying about this radio being used for dual servo set ups. I also need to "save" the channel with the dial control for my smoke pump pot. No way to set wing and tail type. I ordered a Smart Fly Equalizer just in case my radio couldn't cut it. Steve

2robinhood

I think what you are looking for is this setting.
One servo in port 2 and one servo in port 5.
AILVATOR : ON
AIL3> 0%
AIL4> 0%
ELE1> 100%
ELE2> 100%

Let me know if this is it?

2robinhood

The smartfly will fix all of that. That's what I use in all my 35%'ers
You don't need to use the flap knob for smoke, asign it to channel 7 and asign it to a switch.
Then if you are using a Sullivan Skywriter or another programable pump, use premix #1 to mix channels 3 and 7 ( channel 3 master & 7 as the slave ).
When you turn your smoke switch on, the pump will advance with the throttle.
I have mine set up so not much pumping @ 1/4 throttle, more @ 1/2, more @ 3/4, and 4 oz. per minute @ wide open.
You will have to play with the %'s to get it to mix right and right amount, but it will work.

In my 35%'ers with the smartfly, each elevator servo runs right to the power expander, no mixing.
I do mix 1 as the ailerons (channel 1 and 5 ) so that two power expander ports to the left wing and two ports to the right wing.
Mix 2 as throttle to smoke ( channel 3 and 7 ).
All other mixes are for flight triming.

2robinhood

The only way to have two elevator servos from the same RX port is to use a servo reverser.

millerhill

My Feedback: (19)

robinhood:

Thanks all great information!

I used to live in Egg Harbor about 30 years ago. Made it down for the OC Bob heli gathering a couple of years ago. A lot of fun.

I'll give these a try today and see what happens.

By the way...is there a way to test the smoke pump without actually running fluid through it?


Best,

Steve

millerhill

My Feedback: (19)

So, am I better off using the servo reverser or stick with using the Equalizer?

2robinhood

I use a remote needle valve between the tank and the smoke pump ( suction line ) for fine adjusting to get it exactly where I want it.
I use to empty soda bottles ( 100cc engine, so two smoke lines, one for each muffler ) mark them at 4 oz. and program the radio to pump 4 oz. per minute @ wide open into each bottle.
I tried water, but it isn't the same. Use the smoke fluid and you know it will be right.
So the 100cc is actually 8 oz. per minute, ( 4 oz. per muffler ) .
Here is a video of one of my 100cc's with smoke.

http://www.youtube.com/watch?v=ImBZj_PjjzI

2robinhood

Power expander is better. Each servo will have full power. If you use a reverser, you will be running two servos from one lead to the RX.
That is what a Y' harness does. Not a big deal in smaller planes, but35% and bigger has two + servos per wing.
With the expander, ever servo goes to it own port and has full power. The only limiting factor then is everything is powered by the one wire from the battery pack/switch. The heavier the wire, the better.

JoeAirPort

My Feedback: (41)

I'm dissappointed with their manual. I looked and looked and saw no mention of what channels to use for ailavator. I'd call their tech support. Why use another device if you don't have to.

flatspinjim

My Feedback: (3)

Not to interfere too much here, and Robinhood you have given some really good advice, but isn't a power expander a little overkill on this plane? I would hate to see Steve be overwhelmed. Not trying to flame anyone by any means.

2robinhood

Yes it is, I had a brain fart.
I thought he said he had a SmartFly power expnader coming, I looked back and see he sais a SmartFly Equalizer.

My fault.

I di have a power expander in my 30%, and just use it when I stepped into 35%.
Everyone know, you always go , bigger, and bigger, and bigger.

But, yes, my fault, i was reading/thinking the wrong thing.

So, yes, for a 74" plane I would mix channel 2 & 5 for dual elevator and use channel 7 for the smoke.
Don't forget that smoke will add about 1 pound to your plane, and in a 74" wingspan plane a pound can make or break how it will fly.

flatspinjim

My Feedback: (3)

Yep, everyone does go bigger. Hempel now has a 60% Extra. Hmmm

millerhill

My Feedback: (19)

I just tried this and it worked. Nice.

millerhill

My Feedback: (19)

Good to hear. I didn't think I needed a power expander. I do have a dual set of A123's. One for servos one for smoke. I decided to use the OS 1.602 stroke instead of gas to make up for the extra weight of the smoke oil. I'll see how it flies and if necessary, pull the smoke system out. I tend to fly fast and hard, so I really don't want to give up much performance for smoke trails. I'm not into 3D per se, so maybe not an issue.... I'll see what the AUW is when it's done and give it a go.

Steve

2robinhood

Good, glad it worked for you.

millerhill

My Feedback: (19)

Is anyone else flying the yak 74 with a 1.60 and smoke?

2robinhood

I had a Seagull Laser 200 with an OS 1.60FX.
It was a 69" wingspan and was an absolute animal with the 1.60 in it.
I tried putting smoke on it and never got it to work good. I wrapped 1/8" copper tubing around both down tubes of a Brison pitts muffler and then had it inject right at the exhaust port. Trying to preheat the smoke fluid didn't help. The extra ( dry weight ) of the smoke system put the Laser almost 13 lbs on 735 sq. in. of wing area. I just never got the glow engine to make much more then one that is running real rich. I don't have any videos with glow and smoke, but it didn't work for me. I ended up putting the Laser in, it became difficult to fly on stalling stunts.

Too low, on the tail heavy side, and high wing loading =.........................

JoeAirPort

My Feedback: (41)

2robinhood how did you know the 2nd elevator half was ch 5?

Nice work BTW.