Dc3Mek

Hey every one, I'm having problems with a servo reversing controller I believe. It is a small circuit board with GWS printed on it.

I bought the airplane used so I don't know what exactly it is.

The set up is this: Futaba 7c 2.4, Hitec HS 6965 HB servos on the elevator.

The problem is, the elevator is going to different ranges at full throw. In other words, I noticed it when doing full pull loops. The plane would snap to one side. I checked lateral balance and it is spot on. Then I looked to the elevator and sure enough, when pulled hard (Up elevator) the elevator on the right would sometimes go to full travel, and most times would go to something less than full travel. And I noticed that if I held the stick back, then relieved a little pressure the servo would jump to the same full position as the left one.
I then swapped servos on the reverser and the problem traveled to the other side.

So I know that it's the reverser.

I'm new to these servos and reverser and I'm looking for the best plan of action.

Can I just get a Y reverser? Would a Futaba reverser be best?

Thanks for any advice!

Darrell

BuschBarber

My Feedback: (2)

I have not had good luck with Servo Reversing circuits. I have had them pick up RF noise, when using 72Mhz receivers, and I have had the neutral drift on one side, after a couple of flights or when the temp changes.

Generally, Elevator halves and Flap halves need to each have one servo reversed. I usually put Elevator or Flap halves on separate channels and mix them. This lets me reverse one of the servos and fine tune the throws.

If you cannot mix channels, the next best thing is to install a Matchbox. Both JR and Futaba have similar devices. You can hook up from 2-4 servos, to one channel, and fine tune the Neutral, End Points, Servo Direction, etc., so that the servos are not fighting one another and are matched. They are very easy to set up.

Dc3Mek

Thanks BuschBarber, I'll look into that, it sounds like that's what I'll have to do. I have all the available channels used right now.

freeair

GWS is not the greatest unit to have for starters. also do you need to run 2 servos for elevators ? can you get away with 1 only ?

Dc3Mek

I can't run just one servo, the plane is the 1/4 scale GP Extra 300S, so it needs two servos.

I think I'll be looking into the Futaba servo reverser.

As I said before, I can't use any more channels, so I have to use the reverser or matchbox setup.

Thanks guys,
Darrell

airbusdrvr

How many channels are you using? At $40 for the reverser, http://www3.towerhobbies.com/cgi-bin...&I=LXANF2&P=ML , it would seem a long term good investment to just get a receiver with more channels and use your transmitter to do the job.

pilotpete2

Hi Darrell,
The 7C 2.4 should be able to do dual elevator servos, in addition to the dual ailerons.
I fly an Extra 300 with both dual elevator and aileron servos, using a seven channel fasst receiver (R617). How many channels are you actually using?
Pete

Dc3Mek

I'm using all of them Pete. I'm running a Fuji, and have an ignition switch as well as throttle. I'm using the R617 also.
Maybe Airbusdrvr has a good point. Another reciever would only be about 80 or 90 bucks, so.....

pilotpete2

OK, now I'm using only 6 channels on my setup, as it is glow powered. Can't you use ch 5 (gear) as your ignition kill? I realize that in your case you would need a "Y" harness to feed power to the receiver, as the 7 channel fasst receivers don't have a dedicated battery port. Mine's maxed out with the six servos I'm running.
Pete

Dc3Mek

Are you saying that I can use a channel for battery input and control output? I don't understand and I'm new to this reciever???? That would be the ticket if I can do that. Right now the assignments are this...
1 Right aileron
2 Elevator
3 Throttle
4 rudder
5 Ignition kill
6 Left Rudder
7 Battery

Yeah, the gasser takes an extra channel so if I could do that that would be awesome!

pilotpete2

The 7 channel fasst receivers don't have a dedicated battery port, this is quite common and is done to keep receiver size down. The only thing you need to do when all seven channels are needed is to use a standard "Y" connector harness to allow the battery to be connected. The power pins on receivers form a power buss and power can be applied to any of the servo ports (all the + pins and all the - pins are common). I'm not familiar with the 7C 2.4 programming, but I assume that the second elevator servo would be on channel seven.
When using a "Y" harness to connect the battery, get a good heavy duty one from a reputable dealer that makes high quality stuff, I usually use Maxx Products stuff, just don't cheap out
Good luck,
Pete

Dc3Mek

Hey Pete! Problem solved! I should have checked with Bax. He explained some things, and I also did another search looking for "Ailevator" where I found there are a lot of folks with the same exact questions I had. I was just ever so close to doing the right search.

I didn't know until yesterday that Bax is a Futaba tech.

Anyway, I did what you suggested, used a good Futaba Y and plugged it into 7, ran Ignition kill out of 7, changed Throttle cut to the more convenient A switch, set the elevators up in Ailevator by zeroing out the aileron input, so that only the elevator portion of the mix worked. You have to set the elevators up in Channels 2 & 5. The manual doesn't explain this at all!

This gives me everything I wanted! I no longer have the reverser, and the elevators are smack daddy fast! Very little latency, endpoints are perfect, and the initial set up was very easy and linear. All of my settings pretty much stayed the same. Triple rates are all the same... mild, aerobatic and "Hey Ya'll watch this" all as before! I might even try setting up a switched Ailevator in p-mix later, just for some really wild slow flying! I found out that you can do that with the 7C!

Well, hopefully that's the end of this little saga, and I'll be up and flying by Wednesday when I'm off.

For now, it's off to bed, I'm so tired I can't see straight.....midnight shift sucks!!!!!

Thanks for all the help and input guys, I really learned a lot!

Darrell

airbusdrvr

It is nice when things work so well!

pilotpete2

There you go
I'll be using the same setup if I go with a 1/4 scale Edge 540 and 26cc gas that I'm contemplating[8D].
Now if I could just get rid of the latency in my 9C, hmm, maybe the 10C is the answer.
Good luck,
Pete