WattFlyer RC Electric Flight Forums - Discuss radio control eflight

WattFlyer RC Electric Flight Forums - Discuss radio control eflight (https://www.wattflyer.com/forums/index.php)
-   General Electric Discussions (https://www.wattflyer.com/forums/forumdisplay.php?f=3)
-   -   I'm in servoless retract hell!-Advice needed (https://www.wattflyer.com/forums/showthread.php?t=73864)

dahawk 06-10-2014 02:17 AM

I'm in servoless retract hell!-Advice needed
Having a problem and I’m stumped.
Bought a set of all-metal , 120 size w/ 5mm pin servolless retracts from HK for my Piper Cherokee/Arrow conversion. All was working okay until the nose gear stopped working . Nada. No power, nothing.

I pulled it out. Went to buy another HK nose gear but they don’t sell them separately. Go figure.

So I bought a stand-alone 120 size nose gear from PW-RC. Bench tested then installed in plane.

Reconnected 3 way“Y” connector , flipped the gear switch and ? The mains go up while the nose gear goes down and vice a versa. Tried swapping leads around and same thing. Tried plugging in nose gear alone to get it in synch and it doesn’t work. Something amiss here. They will not cycle in unison.

Even tried reversing gear servo on TX. No go.I notice when the plane first powers up the HK mains cycle without flipping the gear switch. Ittakes the move of the switch to change the nose gear. But thenthe mains go down while the nose comes up.Ugh !

I have a DX9and am using an 8 channel RX. Is it possible to program a mix? Have extra channels available. EG. Plug the nose gear into Aux 2 and run the mains on a two way Y connector?Program gear to aux 2 ?I’m running short of ideas.

Have never experienced this problem before.

Any ideas?

fhhuber 06-10-2014 02:30 AM

Use a separate channel for the nosegear mix to the mains and reverse it.

Its the old Futaba vs JR "which way is left" issue... legacy of + shift vs - shift FM

CHELLIE 06-10-2014 02:31 AM

maybe a servo reversing unit might work for you.



dahawk 06-10-2014 03:10 AM

Well I tried plugging the nose gear into aux 2 and assigning to the same switch(gear) A as the mains. Used 2-way Y connector for the mains and it worked. But then the port side main stopped working. Crap. This plane has gremlins !

dahawk 06-10-2014 03:15 AM

Must be a loose wire or bad connection somewhere. Diagnose tomorrow.

dahawk 06-10-2014 07:58 PM

Pulled the port side retract. Tried it stand alone. Nada. No click, growl, budge, nothing. One out of 3 worked.

So, I went ahead and ordered some 120 size mains from PW-RC. Phillip carries a nice mix of this type of gear.

Bottom line? HK all metal 120 size retracts are junk. Not even going to go through the painful hassle of returning.


xmech2k 06-10-2014 09:20 PM

I heard some of those gear are finicky about the servo signal they see. They are just looking for a certain signal range which gives the command for up or down. You may still want to experiment with the one gear. Set the up and down servo endpoints higher or lower in the tx and see if it responds. Then hopefully if something works the other ones will be ok with it.

dahawk 06-10-2014 09:55 PM

Thanks x,

I will give that a try. Makes perfect sense.

CHELLIE 06-10-2014 10:50 PM

Servoless Retracts are Nice, But they can be a PITA :eek: I prefer the mechanical retracts with a separate servo, its less Hassle and Cheaper IMHO

xmech2k 06-10-2014 11:04 PM


Originally Posted by CHELLIE (Post 950267)
Servoless Retracts are Nice, But they can be a PITA :eek: I prefer the mechanical retracts with a separate servo, its less Hassle and Cheaper IMHO

:eek: Less hassle? Personally, I've had one plane with servo retracts and and they were nothing but trouble with a capital T! I've only had one servoless retract problem. It literally just let out its magic smoke once when I plugged the plane in. Plugged in a replacement, off she goes!

waytooslow 06-11-2014 08:55 PM

so how did it work out Hawk?

dahawk 06-12-2014 03:13 AM

I'm afraid it did not work out quite yet. Went to the servo setup screen on the DX9. Played with the travel range on the gear channel. Plugged faulty main retract directly into channel 5 on the rx. . Won't come to life.

I think there's another screen to look at. It's as though it's not making a switch or not detecting the current.

fhhuber 06-12-2014 03:23 AM

Y with (or just plug in) a normal servo to see what travel range is being sent to the retract...

hillbille 06-12-2014 10:03 AM

I thought the HK servoless retracts want 125+ on "travel" for the switches. Basically the ic circuit in the retract "looks" for "0" and then for "125+" to operate. Futaba are usually set to "max" and do not seem to have a problem actuating these, but Spektrum only sets "100%" for it's travel and needs to be set to "125" for these to work.

I think I had a set that would only actuate if the travel was set to +125 on the one side and -125 on the other, and anything less wouldn't reliably actuate them on my DX8.

PITA though trying to set them up without knowing what it takes to get them to work!


dahawk 06-12-2014 04:14 PM

Thanks Hillbillie ,
Worth a try.

dahawk 06-12-2014 09:24 PM

In the servo setup screen for the DX9 , the max travel value is 125% . So I tried a variety of combinations, nnet of which unlocked the secret retract code. 125/0, 0/125, 125/125 , 0/0. You name it I tried it. Connected individualy and via a Y connector.

Originally, all three worked. Then, the nose gear went to sleep.Dead. So, I bought a new one from PW-RC. Then briefly , or should I say" momentarily, all three worked again and I thought I was done. Declared victory and spiked the ball.

Rut-ro !

That's when the port side main took a hike. Two dead. I guess one out of three is pretty good for a batter.

I have a sneaky suspicion I'm missing something. Waiting for the ' aha' moment as in: Aaahh , now I get it !" . "It was the doo-hickie / thing a ma chig. "

Set up a test with an esc/motor and rx. Tha's what I;m using to test the retracts. Checked cables, connectors, etc.

xmech2k 06-12-2014 09:42 PM

Voltage, power source?

dahawk 06-12-2014 09:50 PM

14.8V lipo I did hear these can't take more than 6V, not even 6.1 Not sure what got fed to them by esc. Maybe I fried them?

flying-barely 06-13-2014 04:19 AM

6VOLTS max on the retracts. What esc are you using? Does it have a Bec? If using a separate power source for RX, what is it? You cannot run 14.8 volts to the RX either.
Normally becs built into the esc's are 5 or 6 volts with some giving the option between these two. Separate bec usually provide a choice of 5/6v. A battery pack must not exceed 6v or the retracts will burn!!
If you require a mix to gear, look at aux 3 or aux 4 with switch to operate with gear.flying-barely

kyleservicetech 06-13-2014 05:11 AM


Originally Posted by flying-barely (Post 950397)
6VOLTS max on the retracts. A battery pack must not exceed 6v or the retracts will burn!!

That 6 volts maximum rating rules out the use of either a 5 cell Nih pack, or a two cell LiFe/A123 receiver pack. :eek:

xmech2k 06-13-2014 07:18 AM

Well since they plug into the rx they should be getting whatever voltage the rx gets.

dahawk 06-13-2014 03:40 PM

I believe the esc has a 6v linear bec.

waytooslow 06-13-2014 04:03 PM

hawk -- when I worked on your nose gear trying to get it to respond - I used 4.7 volts and the 6v. the same results. If I manually moved the gears to deactivate the momentary end point switch, the motor kicks in and the gear would roll until opposing switch was activated. I think there is an issue with the switching circuit

dahawk 06-13-2014 04:09 PM

Thanks Man,
That is way over my limited tech capability. Why can't they just make something that works as advertised ? Shouldn't have to go through this.

waytooslow 06-13-2014 04:13 PM

DEFECTIVE - send it back

All times are GMT +1. The time now is 06:45 PM.

Powered by: vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Page generated in 0.04696 seconds with 12 queries