FMS F4U Corsair V3 - landing gear sequencer

[skdenes]

Hello guys,

I have a Radiolink AT10+FMS corsaiar V3. My problem is, that I can't make the landing gear work.
- If I connect directly on the wings, I can operate 1-1 the door and the gear.
- same on the panel
- with the sequencer, no output.

I even tried to put the channel to a knob, modified the end points and moved throught the whole range ( I mean the knob), but the sequencer does not engage.

Do I miss something or time to order a new one ?

Thanks

[xviper]

I don't know anything about your Radiolink but I would think that it shouldn't matter what kind of radio you use as far as making the gear/gear doors work properly via the sequencer. I have the V2 and it seems that Horizon does not provide an online manual for the V3. In any case, since there is only one lead from the sequencer to the RX, the only thing to remember on that connection is the polarity. If wrong nothing will work.
In my manual, it shows the sequencer and the connections involved. I do recall that after doing some repairs to the retracts, nothing worked right. IE, the doors did not operate in the correct sequence and sometimes a door or a gear would not work at all. Looking at the wiring going to the connectors in the wing and looking at the sequencer, I realized that I had the retract and the doors on one side plugged into each other's slot and in one instance, the polarity was all wrong. Additionally, close inspection of the sequencer indicated that I had the polarity of one or more plugs wrong and again, the plugs were in the wrong sockets, thus making the doors work at the wrong time as the retract or not work at all.
Rather than doing all your testing via a powered up TX and RX, the use of a servo tester at various locations is a much better diagnostic method. Start at the door servo and test it and open the doors. Then test the retract. Plug those into the wing connectors and then test where those main leads come out. Again test, the door, then the retract. Plug those into the sequencer and test the sequencer to see how it works. Repeat for the other side. Then use the tester on the main lead coming out of the sequencer to see it all of it works.

[skdenes]

Basically I have already checked the hub on the wing, everything works.Next step was the main board and its wires towards to the sequencer. At this connection point, when I installed my receiver, everything was worked (I just had to use 2 channels and switched to operate the door and landing gear).

When I move 1 step forward and connect my receiver directly to the sequencery, nothing happenes.

[xviper]

Could be a bad sequencer. Have you confirmed that the gear port on the RX is functional?

[skdenes]

I am beginner to all of this. Only a gear port (on my Radiolink,this is officially CH5) can be used for the sequencer or any other ?

[xviper]

I am beginner to all of this. Only a gear port (on my Radiolink,this is officially CH5) can be used for the sequencer or any other ?

All the sequencer does it to operate one servo before operating another on the opening step and reverse that sequence on the closing step. The gear port is defaulted to sending out a signal at both ends of the switch throw. Use could easily use a different port that is operated by a switch. For example, you could plug the gear lead into the flap port and operate the gear by throwing the flap switch, just NOT stopping in the middle position if your flap switch is a 3-position switch. In Spektrum, the electronic signal from the switch positions goes from -100 to +100. I think your Radiolink does something similar. In fact, most of the higher end Spektrum TX can do the sequencing internally WITHOUT the use of an external sequencer. You plug the retracts into the gear port and the doors into another open port and you program the sequencer inside the TX which port is doing what and to operate one before the other, with your designated time interval. These sequencers are nothing magical. They just need one signal or the other (two ends of the switch positions) to work. It does the delay in its own circuits - one signal input, two steps output.

[skdenes]

got it, I've ordered a new one, I hope it will work.

[skygeezer]

got it, I've ordered a new one, I hope it will work.

Did this solve yourproblem? I have the same issue with mine and am using a Spektrum DX-18 tx.

Very frustrating!

Thanks…

curt

[skdenes]

Hi,

at last I've ordered a new one. (previous was also new Haha...), well the second one can operate 1 servo from the two, so it is 1 step better but still ****...sorry, I can't belive that nowadays, you can have 2 brand new sequencer, which are not working properly.

OEM no f* answer for my complain, distributor said, that it is always checked by the OEM, all should work, jepp, thanks, I can see it, how well they are working

[Ces308]

Hello Corsair pilots and maintenance crews! I also have a FMS1700 v3 Corsair had a problem with the gear right from the start. The first one , after I got it together the main gear doors opened and let the gear like it should. Then when retracted, the main gear doors closed before the gear went up! No one knew anything as what to do to fix it. I sent it back and got another one from Tower hobby and it did the same thing! This time I played around with it and moved the gear plug that went to the tail wheel ahead two pins on the board and it worked ! Now I had another problem…. Maybe check your too… the push rods that go into the horn on the servo to the main doors hit the center of the servo as it turned and stripped out and burned up that servo. I removed the rods and ground off a little on the z end so it wouldn’t hit anymore. Also sanded the tail hook where it slides back and fort when the tail wheel retracts. I fly off our sod runway ( 5Y2 ) and if dirt gets in there it will not retract. Oh yeah, the shaft on the main gear that swivels when retracted stops half way up or down. I removed it , polished it up a little, lubed and reassembled. That took care of that problem! Lol For the fun of it, I installed a stall strip on the right wing, about an inch out from the guns. They installed them on the full size one to even the stall as the left wing would stall before the right and pilots were crashing airplanes!

[xviper]

after I got it together the main gear doors opened and let the gear like it should. Then when retracted, the main gear doors closed before the gear went up!

This would indicate to me that the lead for the retract and the lead for the doors are in each others pins. Did you try to swap them? I played with mine after I did a retract replacement. You might want to try with a couple of spare servos not attached to anything. Just plug them in and activate the gear switch to see which one works first and which one works second in both gear switch positions. If you have them plugged into the correct pins, one will open first, then the other (on the deployment cycle) and then the "other" should work first and then the first one. ("First" one being the door, "other being the retract.) The door pins should be clustered together and the retract pins should be in their own cluster.
PS. On my V2, I also found that the labelling on the wing board was INcorrect. You have to confirm things with a servo tester and ignore the printed labels.

[Ces308]

Ok…I checked the plugs in the fuse and all looked good….so I pulled the wing off again and switched the two main cables …powered it up and it worked!