Landing Gear Sequencer

Just arrived the replacement all metal nose gear for Valkyrie albeit this retract is for a Viper 90mm. I will also have to swap out the leg as the Viper is shorter than the Valkyrie. The retract is not electronic, ie; two wire system which means I need a sequencer to reverse polarity to the retract motor and another output, ie; 3 wire for PWM for gear door. Any suggestions on a cheap sequencer? MotionRc cannot help because all their retracts are electronic versions

Phil - Might be worth a look on Model Radio Workshop - www.modelradioworkshop.co.uk
Colin.

Have a look at the nose gear doors of the FMS PC-21, passive operation no extra servo/electronics. I've got one if you'd like to see how its done.

The new all metal nose retract is only two wire. It does not have a signal wire like Eflite, Jetcraft, etc, where the electronics to reverse the motor are built in. Therefore it needs a controller (see example images below where you will see only two pins for the retracts on PilotRC and the RC Lander units) which switches the polarity to change direction of motor. In most cases the controller also sends PWM signals to servos for doors etc.

Really stuck on this issue to get an operating nose leg to work with minimum fuss.

Phil Ford wrote: Really stuck on this issue to get an operating nose leg to work with minimum fuss.

Minimal fuss = don't order retracts without a signal wire

I've still got this hobbyking front leg or I might be able to repair the old one

joneb wrote: I've still got this hobbyking front leg or I might be able to repair the old one

Thanks John but the nose gear plate is quite large, in fact larger than most EFlite retracts. Bear in mind this leg has to take the weight of 90mm EDF. Looking at a whole set of retracts for giant scale turbine jets many use the two wire system as pictured in my images. But for one nose leg you wouldn't want to buy £120 worth of controller. Well I am not!

What about this Phil

Thanks John, I did come across some projects using an Arduino. Although the Arduino for timings, etc but still require the signal (PWM) line. Anyway I have downloaded the ino file for later play. The gear I have needs the motor polarity reversing for up or down. Looking at a stripped down image of one these jet jockey controllers it looks like they use our old friend the STM8 chip (found in receivers, speed controllers, "you-name-it" and the motor control forward/reverse is switched by small chips but could not see in the photos what they were. Think they are LB11805 maybe.

Hawk eye John B spotted this controller for an Avios MIG17. Exactly what I need, two pin outputs to gear motors. :woohoo: Coming from Hong Kong though. £8.60 + £3.15 P&P

Thanks John.