witchfingers
70cc twin V2
I am installing the powerbox competition currently. How was the smartfly to program? This one is definitely a learning experience.
Power systems/ Hitec A9?
- Thread starter witchfingers
- Start date
witchfingers
70cc twin V2
My only gripe about the powerbox so far is that it did not come with power leads. They are a goofy multiplex 6 prong connector so you can't just pick them up anywhere. Does the smartfly use potentiometers for servo match?
Xpress
GSN Sponsor Tier 1
^The Multiplex M6 connectors are very popular overseas, not so much here. You can actually buy them from Tower:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEXT3&P=7
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEXT4&P=7
They are out of stock, but so are we.
Probably a faulty solder joint in the y-harness.
I use all Hitec servos in mine, 1500 is the digital center point. Being that servos are partially hand made there are some minor variances in the output spline positions, that's where you have to use a programmer to center the servo (or subtrim in your transmitter). I use my programmer in conjunction with a protractor app on my phone to set the center and end points of each servo.
So for example on my ailerons I plug one servo into the programmer at a time and center each of them. Then I deflect each servo to its max limit to find out what the maximum throw will be and I will set the max end points from there. Takes a bit of time and patience to figure it all out but once you do you will wind up with servos that move the same distance on both directions as well as return to the same center point.
I don't have an optical kill setup just yet, I'll eventually get around to buying a spark switch one of these days. My A9X has a throttle kill feature that, with the flip of a switch, moves the throttle servo to the fully closed position.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEXT3&P=7
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXEXT4&P=7
They are out of stock, but so are we.
Probably a faulty solder joint in the y-harness.
I use all Hitec servos in mine, 1500 is the digital center point. Being that servos are partially hand made there are some minor variances in the output spline positions, that's where you have to use a programmer to center the servo (or subtrim in your transmitter). I use my programmer in conjunction with a protractor app on my phone to set the center and end points of each servo.
So for example on my ailerons I plug one servo into the programmer at a time and center each of them. Then I deflect each servo to its max limit to find out what the maximum throw will be and I will set the max end points from there. Takes a bit of time and patience to figure it all out but once you do you will wind up with servos that move the same distance on both directions as well as return to the same center point.
I don't have an optical kill setup just yet, I'll eventually get around to buying a spark switch one of these days. My A9X has a throttle kill feature that, with the flip of a switch, moves the throttle servo to the fully closed position.
Last edited:
djmoose
70cc twin V2
Just some friendly constructive criticism. No harsh feelings here...just expressing my opinion.
1. Does the A9x actually center it's channels at 1500? The OG A9 did not....which makes using the hitec programmer rather pointless unless either your (different brand) radio DOES center at 1500...or you use subtrim to achieve a 1500 center point....which in turn robs you of throw in one direction. I haven't measured the A9x...so it's be really cool if Hitec (and I love you guys...I'm friends with all of the Hitec folks) sold radios that matched up perfectly with the programmable servos and servo programmers they sell. (the above procedure requires you to learn about pulse-width and buy one of the very few easily available tools to measure it with 4 significant digits.
How to solve this VERY EASILY: Make the Hitec programmer allow you set the center value pulse width to match your radio. Make it a variable in the program and you're all done....exact perfect programming in one step with any radio. (after you measure your radio's channels) (note: Futaba's programmer is locked at 1520 for center and can't change....which means you might be closer if you use a futaba radio...but my 14SG centers at 1524. (people will look at this figure and claim that's not a big difference....my reaction to those folks is that we're programming servos to BE EXACT...not close.)
2. Y-ing any two servos (with a typical HD servo Y-Harness) on a plane larger than 30cc is (in my humble and honest opinion) a safety hazard. Yes, it'll work. Not very safe. Now...throw in a distro board....program accordingly...you're good to go. Wire up a custom harness to keep the servo power buss out of the RX and have dedicated power to each servo? That's totally cool...Y-Harness that signal wire and you're golden.
3. Not having a TRUE kill option on a 100cc plane is also a safety hazard. What if your throttle servo dies or locks? What if your servo arm detaches because you forgot to bolt it on while trying to get your perfect throttle geometry? (trust me...I resemble that example) Yes, some engines have throttle springs...but a lot of people take those off...can't cont on them being there.
I love Hitec...I love the OG Aurora 9 (I still have mine). However, I don't really think it's a good idea to justify stretching it's channel capability for use in 100cc planes by providing unsafe plane setup examples/tactics. I also have never really appreciated Hitec's claim that programming their servos is easy...it's not...even with their own radios.
In direct response to @witchfingers original question:
Lastly...I'm not saying it's impossible!!! My 3DHS 103 Extra with ganged aileron servos runs on 6 channels. That being said...I have a large distro board and the servo power does not run through my Rx. Each servo gets it's own wire and dedicated power.
Just be careful, plan ahead, and stay flying. Set yourself up for less failures.
Just my opinion again, hoping to shed some light on a few things.
Xpress
GSN Sponsor Tier 1
Hitec uses a 1500μs centerpoint for all of our equipment. Keep in mind that there may be some slight variances from A9 to A9, as well as A9 to A9X being that the A9 is a standard resolution and the 9X is high resolution.
I matched up my Hitec servos with my Hitec programmer no problem just this weekend, and it all worked kosher with my A9X and O9 receiver.
You can measure the centerpoint with the HFP-25 that the transmitter is emitting out to the receiver. I have a feeling our R&D department will be releasing a new version of the HFP-25 sometime soon, but I don't know anything else at this point.
We've been doing it for years without problem, even before widespread popularity of intelligent matching systems came about. It's not an issue if your servos are all matched up properly, but it can become one if you don't match center and end points properly. With all of these points matched, your servos won't fight each other and everything will be even.
What do you think we did way before we had the option to use intelligent matching systems?
We also didn't have reliable electronic remote kill switches in the old days so we often did without them. This is also why you need to do your proper safety inspections of your airplanes before flying them- that includes going over all of the nuts and bolts to your servos and linkages. The only reason I'm adding electronic ignition kill to my own airplanes is because they are required at certain events.
We are very spoiled with all of the bling options nowadays that aren't necessary. With a properly setup airplane with correct linkage geometries, there's no need to use channel expansion and intelligent matching systems. You are doing almost exactly the same thing with your transmitter if you run each servo to their own channel and use subtrim/end points inside of your transmitter with the only difference being that, with your transmitter you set center and end points inside of the transmitter, and with servo programming you set the center and end points inside of the servo.
And if it's current capability you're worried about then either purchasing or making your own HD harnesses is simple enough
It's actually very simple, and I can walk you through it in about 5 minutes if you would like. Keep in mind I don't program servos on the daily, very rarely if ever do I actually use the programmer or program servos.
I set my 100CC up this weekend so that my ailerons are on one channel for each wing panel- matching the 4 servos took me somewhere around half an hour, it's not really difficult to do.
djmoose
70cc twin V2
What are the pulse width measurements of you A9x with 140 EPA?
My a9 is the following:
low: 958
center: 1512
high: 2077
Here's a question that I haven't been able to figure out.
Why is it that the Hitec Programmer sets the servo's end points at 900 - 1500 - and 2100....when my A9 can't even go that low or high in pulse width?
We've been doing it for years without problem, even before widespread popularity of intelligent matching systems came about. It's not an issue if your servos are all matched up properly, but it can become one if you don't match center and end points properly. With all of these points matched, your servos won't fight each other and everything will be even.
What do you think we did way before we had the option to use intelligent matching systems?
We also didn't have reliable electronic remote kill switches in the old days so we often did without them. This is also why you need to do your proper safety inspections of your airplanes before flying them- that includes going over all of the nuts and bolts to your servos and linkages. The only reason I'm adding electronic ignition kill to my own airplanes is because they are required at certain events.
Remember when cars didn't have seat belts? That's how we used to do it....doesn't mean it was safe. Smoking and drinking while pregnant? Remember that? just because that's how it used to be done....doesn't mean it's safe.
Exactly...however the point of all of this is that what you just described is kind of hard on a 100cc 3d/high performance plane with only 9 channels. If you do what you just described...you can't run dual rudder servos or smoke. (not even thinking about BOTH dual rudder servos and smoke) I was simply not agreeing with your notion to y-harness some channels to free others up.
Mods and Admins...this might be getting off topic a bit...so feel free to split this off into a programming thread (I won't be offended)...however, it does all have to do with the 9 channel limitation of the A9 radios.
Xpress
GSN Sponsor Tier 1
It is capable of 900 and 2100 on a switch. I don't have the tools to measure one lying around my desk.
It's giving you the extent of what the servo is capable of listening to. Push and hold "M" while in the Auto test mode and it will cycle through all of the pulsewidth numbers rather than just 900 and 2100.
We're talking about toy airplanes here...
I have dual rudder servos on my 100CC. I just have them in an SWB tray, no need to match anything in that tray (but I did anyways), I just y'd those to my receiver too.
No need for another discussion, this is all relevant to the Aurora 9 or 9X systems.
witchfingers
70cc twin V2
I actually have no problems using the hitec programmer. This 100cc plane is not the first dual servo aileron plane I have done. I had a lanier yak 54 that had a dual servo aileron setup and I had no problems getting those servos spot on with the a9. That plane was electric and I had enough channels to have two separate lipos running hitec hv servos and no regulator.
witchfingers
70cc twin V2
Here is the plane. It flew great, it just needed a gas engine to haul that heavy airframe.