Ultrastick Wiring: RCEXL Opto Kill Switch is NOT an BEC

Spent some time in a conversation with Google Gemini (their AI) and learned a lot I hope I knew and forgot about how the opto kill switch is not an IBEC.

The diagrams for the RCExl Opto Kill Switch look like this:

The RCEXL Optical Kill Switch does two things. It uses a light junction to separate the hard wire electrical connections so the 20,000 volts of noise generated by the spark plug do not flow back into the receiver and electronics interfering with them or frying them altogether, AND it serves to kill the power to the ignition. Power to the OKS passes through, so my 2S 7.4v LiPO would send up to 8V to the ignition, if the light sensor inside the is on. Here's how Gemini explained it:

The RCEXL unit has two sides that are "optically isolated" (connected only by a beam of light inside the chip) to prevent electronic interference from reaching your receiver:

1. THE RECEIVER SIDE: It plugs into your receiver to  get a signal and a small amount of power just to run the internal LED and the "gate."

2. THE IGNITION SIDE: It has a "Battery In" and an "Ignition Out" lead. You must plug a battery or regulator into the "Battery In" lead.

What happens when you flip the switch:

1. Switch On: The RCEXL unit closes the circuit, allowing power from the ignition battery to pass through to the ignition module.

2. Switch Off: The unit breaks the circuit, cutting off power and killing the engine.

I had my circuit like this:

This works, but apparently it allows interference noise hardwired back into the circuit. Options are a separate battery (two battery system, nice in big airplanes) or one battery and an BEC. Note that with this setup the RCEXL unit LED did not light up... so I think the RCEXL is bad.

Above is how I will be doing this circuit. I purchased a RCEXL Opto Kill Switch with BEC (see below). from Valley View RC. Curiously they are the only place that carries this.

Apparently this (above) is the OPTIMAL way to do this. It protects the circuit by filtering out the feedback, and offers a kill switch. I have one of these on the Pulse XT60 (need to see if I also have a RCEXL switch as this would be redundant).. Pictured below is the Tech Aero one I have, and is most recommended, in that its one of the few out there. Problem is its over $70 delivered, which is why I went with the RCEXL one.  IBEC's, especially one with a LED indicator light, are very hard to find, and nothing under the Tech Aero price.

I did drop by the workshop to check a few things, like do I have a IBEC. I have a UBEC but Gemini did not recommend this with the kill switch, and it added more complication to the circuit. I built a little holder to secure the receiver pack, and removed the RCEXL kill switch. I will likely return the one arriving today from Amazon as I don't need it, and am waiting for the one from Valley View, coming by some dude on a bike from Indiana, maybe 3-5 days?  Tomorrow I may try firing up the engine without the kill switch, wiring in directly to the battery through a 5V regulator. I am concerned that the touchy EVO 10cc will try what little patience I have left (hence today a day of rest).

A good day!

Memorial Day.

I took the Alpha Sport 450, the Hacker MX2, and the Pulse XT60 out to my old flying field, Jopa Hill Fields in Bedford, NH. 

The grass is nice but too long, so the Alpha and Hacker has issues. Then a cheesy wiring solution converting the Alpha from EC5 connector to EC3 went wonky, so she didn't even get off the ground. Fixed that when I got back, did it proper.

The Hacker could get off the ground with max elevator and gunning the throttle. Flew wonderfully and I flew 6 batteries, just practicing basic airmanship. Landings were a bust due to the the long grass, she would just tuck in and flip.

After that I felt more or less ready to take the pulse XT60 up. She started right up and ran wonderfully. She still is a bit rich in high, manifesting as a step down when the throttle is quickly brought from full to idle, but it's quick and she reduces well to a good steady and reliable idle. Full open she rocks! As expected, the 15 inch prop doesn't provide enough clearance in grass, so the first landing she prop-stoped herself, and in the second she just broke the prop. I ordered the 14x9x3 I should have done before (am adjustment from 14x7x3). This will give me another half an inch which I hope suffices as I can't go lower on the diameter. I also went up to 9 from 7 on pitch. This should be a nice prop.

I still don't have a formal field with a proper grass or geo-tex runway. Hudson hasn't found a new home, Merrimack is a tight hole in the forest and a bit far off. There's a club in Serry, I think, but they are also in a tight niche with high power lines right there. So I will need to deal with the grass at Jopa. At least it's so much smoother and not as clumpy as several years ago when I last flew here.

Good to be back in the air!

Great Flight Day!

The weather was perfect, occasionally gusty, but right down the runway North-to-South. I packed out the RCGF-USA 26cc PulseXT 60, and the newly repaired RCGF-USA 26cc Phoenix Waco F5C. Excited to get to the field, and fly, fly, fly!

Love this plane, the Pulse XT60! It flies sweet, is fast as anything I have, with power to spare!  

SO much frickin' fun!

Since replacing the sparky the  is back to her old reliable self again. What a joy to fly!

The Waco was ready to fly, and fly she did!

I flew her for a 20 min flight, getting her trimmed out. She needed a bit of nose down trim, but roll was fine. It was a bit gusty up high, but she handled it well. Take off has to be done gracefully, slow power up, just like the real Waco. She is squirrelly on the ground with a tremendous P-Factor (that's how she ended up in the weeds last year). A bit touchy in flight, but I was getting used to her and in the end was feeling very comfortable with her.

On my second take off as I was gaining speed she caught a clump of grass and tipped enough to ground strike the prop, breaking it, and flipped. This side of our field (the gasser side) is lumpy, adding to the take-off challenges. Fortunately I have another 18x10 at home, and she is already back up.

I expect to take this duo out again next flying day!

Pulse XT 26cc RCGF engine running better after cleaning

In hopes of solving the sputtering and 4 cycling that has plagued my RCGF-USA 26ccsince last year. Yesterday I pulled the engine, rebuilt it (left the cylinder on the crankcase, those bolts weren't going anywhere), and completely  dismantled and cleaned the carb. The parts and gaskets were all fine. On the diaphragm side there was a surprising amount of fine grit in the pump side. I wonder if thats what the main problem was? The enginenisnt running perfectly mbut its so much smoother. Right now the sputtering is softer and only at wide open throttle (WOT).

The engine before breakdown and cleaning.

After the breakdown dn cleaning. 

Hangar 9 Pulse XT60 and its RCGF 26cc Flight Ready

 After yesterday's debacle, I moved forward with getting the rest of my fleet flight ready, today starting with the Pulse XT60.

Took her off the wall and out to the work table. Decided not to lug the wings out just yet. Spent an hour running her and tweaking the needles. She started right up and ran pretty well, but I felt she was running rich still. 

 After repairing the stripped aileron connector, I attached the wing and ran the engine to see if the ailerons wanted to play the fool and jitter, but nope, all is well. Has only been a problem on the Stik and the Stick.

I'm pretty happy with her and look to take her out tomorrow, weather permitting.  I will do a few cosmetic fixes before then.

This is right after starting her having had her on her back repairing the lead. She had to cough up some air first. As I wound the needles to full closed to reset them I stopped counting after about 4 turns... I set them at 2 and 2, finding that's the min to start and run up, probably ended up closer to 2-1/2 for the high, but closer to 3-4 for the low to get a smooth run up. It still stutters a bit with crash to WOT, but its quick and consistent. Last year she ran smoothly on the ground, but 4 cycled in the air at WOT. Will see.

Next up, one of the 30xx's and the helis. I am still putting off fixing the Waco, and maidening the 3rd Spitty.

First Flight of the Season

 

It feels like I got off to a late start this year... 

I usually fly almost all year around, but work this past year took so much of my time that I left most of my hobbies behind. Now that I am "on sabbatical"  between gigs, I have some time.

I updated the iX12, expecting that to derive any number of nightmares, but it actually went pretty flawlessly. I think. It may have this new trick where it needs to have the battery unplugged and plugged back in to turn on, but we'll see. I charged it up completely having let the batter die over the winter. Update done. Cleaned out the planes I killed last fall, no need to be reminded every time I scroll looking for today's aircraft.

I took the Eflite Alpha Sport 450 out, as the first plane I fly every season. It was my first real plane, the one I learned to fly some 11-12 years ago, and I know it so well that it's comforting to renew my thumbs every season, and settle the "new field jitters" when I fly somewhere I haven't before. I thought I had taken a photo at the field, but alas... I did take a pic of the Cubbie. I flew several packs on the Alpha, and then just one on the Cubbie. It was a bit gusty, so the Cubbie took a beating, but landed fine. The grass at Wason Pond, in Chester, NH, where I went today instead of hauling all the way out to Hudson, was long and clumpy, so I took off from the dirt on the baseball diamond. 8 packs in all, about 40 min of flight. The first flight I overcontrolled a little, but by the end I was hand launching with no issues. It really felt good. A dad with some kids had just finished flying a Blue Angels F-18 Kite, enjoyed the show and I invited them over for some show-and-tell!  They loved it, and it was good to see them so happy. The dad has found a new hobby!

Tomorrow I think it's time to get the 10cc Ultra Stick flight ready, see if I can solve the "flickering left aileron" problem. Then the 26cc Hanger 9 Pulse XT going. Think the two 30cc's will follow. I am scared of maidening the 10cc Spitfire... past being prologue, but that too will come. 

And not let us forget the babies, my helis!!!!

A Pattern of Destruction: Spektrum iX12 Doubts...

We begin with the acknowledgement that I am and always will be a total Spektrum Fanboy. No company has been more progressive in developing technology, and until this debacle I have never had any issues attributable to the radio system. Its just hard when you get scared of using a radio, but I am reassured this is not an unfixable problem and that Horizon Hobby will make this good. There.

Prelude: Two days ago, final flight of the day, lost controllability of my Trex 450 using my iX12. I simply had no control authority in the final several seconds of flight. No telemetry on this Orange receiver, and the receiver was ejected from the ESC wire, so no blinking "holds" clues. The battery had 3.89 V per cell still. I was simply flying straight, slight down attitude, and she stopped responding. Since I had nothing else to attribute it to, I checked it off as that once in 10 years signal loss. Pretzeled the heli, already rebuilt it. This was the last flight on my iX12. Everything worked fine afterwards... 

What happened today made me very doubtful about my new Spektrum  iX12 radio, it being the most likely cause. Spurious reports on the webs suggest that this isn't common, but also isn't an isolated problem. The 450 accident (and to think of it, the loss of the Ugly Stik back in June might be related), then this, causing a loss of confidence. I love my iX12, just need to be able to trust it.

This was the next flight, and the first since I lost the 450, and first flight of the day. Took my RCGF-USA 10cc Sukhoi SU-26 up, engine running great, flew touchy as it does, quick landing and hot adjusted the Expo up a little to 40% all around, and took off. Again flew fine. She has been in the air for about 15 min. Flying along the treeline just above the tops about 1/4 mile away and she seemed not to respond to elevator as I tried to move away from the trees. Thought maybe I wasn't flying her, just thinking I was, but she responded late and cleared. Decided to do a low speed low pass and turned to final. Dropped the throttle to idle to slow her down a bit... but nothing happened. Wiggled it, no response. Tried to pull her up out of an increasingly steep dive, no response. She is WOT with a slight nose down attitude, then suddenly straight down into the ground. I mean straight. From the wreckage pattern you can see she is tightly packed all in one spot.

Again, level-ish flight, nothing going on, just stopped responding to inputs. The Spektrum AR 7010 receiver light was steady, no signal loss, and all the controls/servos worked, except the totally crushed throttle servo (crash even stripped off the servo's stickers), so no signs of actual signal loss. Just loss of controllability. Now remember, this makes two consecutive flights on the same transmitter. That's not good. So setting up a service ticket and sending it to Horizon Hobby for a look-see. They have ALWAYS done good by me, which is one reason I prefer Spektrum.

Oh, and by the way, yesterday I bumped the G switch lever with my hand going for the H switch while bench working a heli, and damned if the thing didn't snap right off! Must have banged it on something before that loosened but didn't detach it. Have them fix that too. I can fix the ones on the DX's, but I am told that this one has the switches "on the board" and they are a bit more involved. Besides, I don't want to open the back until HH/Spektrum takes a look at it.

Next iX12 gripe: I have tried a couple of times to export the aircraft files to the SD Card, but all I get is a set of empty folders. Maybe the files are not in a format a PC can see? This happens every time I try to back up the files. Formatted in FAT32. Have a query out to the Facebook iX12 group.

UPDATE: Found a YouTube Video on how to do it, not intuitive at all, but once learned easy to do.

So for now I am grounded. I can program a couple of planes into my trusty Spektrum DX8, but I have to do that for everyone of them... and the helis are not easy to manually transfer over. I may put one of the 600's, the 500 and the Pulse XT60 on it. I think the Waco is still bound to the DX8 as I hadn't moved that one yet.  I suspect it will be well over a month before I get the iX12 back.

Once I get around to it, maybe tomorrow, I will tally up the butcher's bill on the Sukhoi. The spinner and prop on the engine look undamaged but I think the sparky is cracked, and the muffler pipe snapped off. The fuse, of course, is matchboxed, but the servos, receiver and battery survived.

Not good at all. In our hobby you have to trust the radio system, a lot of time, money and effort are banking on it. Grateful it wasn't one of my irreplaceable planes like the Pulse XT60, or the original Eflite Stearman, or an expensive one, like a 600 heli. That would have put me off my feed for a week.

COMMENTARY:  Reading the responses on Facebook I always am annoyed by commentaries by people who bash clone recievers like the Orange one on the 450, failing to recognize there is no data to support they are inferior, and that this one has been on this heli for years without problems. Its on that aircraft because it was what I could afford, and has worked fine. I enjoy hearing ideas from others, but think about the data and circumstances described, and reason it out. If you don't have the technical knowledge to back you up, keep silent; for example antenna length doesn't increase range, its a requirement of frequency, and the helimwas 10 feet away with the reciever antenna facing me without obstruction, and has a satellite 90 deg offset. If you then have something to add, share, but if its just to bash, or without thought, its just embarrassing. Orange recievers are fine. Now that I can afford them, I use only Spektrum, but that is no guarantee of reliability over an Orange reciever. Thousands have used them without a problems for thens of thousands of flights reliably. Don't be a hater.critically. Learn how to think critically.

Heli magic, Pulse XT60 Noise

Gnarly skies, but no wind to speak of!

Brought out the HK500 FBL and flew two wondrous packs! 

She flew wonderfully. I gained confidence and felt in control. A couple of errors were quickly recovered from, flew nose in and landed, took off again, never out of control. I really enjoyed it! Was ready to fly some more, but some others showed up and I don't really feel comfortable with others watching. I am going to get the other helis set up on the iX12 and focused on flying them,  and more sim time!

The Pulse started fine, but for a couple of times would slow and quit at WOT after a minute. This stopped. On the ground she is pretty smooth, a little 4-cycling. Up in the air she flies well, but gets really noisy with sputtering and the occasional backfire at WOT. I don't know why this happens. It's weird, but she otherwise works great. I have taken to flying 40:1 because of the oil spitting, mostly in the 10cc's. I don't think it will make a diff, but I am going back to 30:1. I thought it might be rich, but the needle is cleaned out as much as is good, and I read 4-cycling isn't from being rich, and that a little is normal. I don't know how to fix it. I worry only because I don't want the engine to be damaged, especially the occasional backfire pops which scare me. Have to wait to test it.

Oh, this pic. Not a crash. Landed fine, taxing in, made a turn, and all the sudden she dropped on her knees. The hardpoint delaminated, and just came off. 

It was in one solid piece, it didn't break. No damage to the plane. The front tabs were stuck in the fuse, the back one's came out clean. 30 min epoxy, tapped into place snug, then clamped.

For good measure I counter-sunk a couple screws forward, one aft. 

Should be good and sound! 

Waste of Time: Take 2

Brisk winds. Brought out the Stik with its RCGF-USA 10cc, and the Pulse XT60 with its RCGF-USA 26cc. Both worked fine last week. Neither worked fine today. It took some tuning the 10cc, but that wicked un-commanded aileron movement occurred and was pretty constant at high RPM. I just read a story about a plane crash where the prop was out of balance and generated a vibration freq that caused this to happen. Hmm.... will be checking the balance of the props.

I even had my son Luke with me to video... but alas, nothing flying today. The Pulse was not running right since getting her muffler tightened, and part of it was the fuel lines kinking. I knew this might be a problem at some point and it was today. And to boot, the screw that secures the spinner stripped. Grounded.

Got her home, fixed the fuel system redoing all the lines and making it a 3 tube system so that the engine gets its fuel directly. A new spinner screw was all it took to solve that problem. This all took about an hour or so. I was not in the mood for further foolishness so called it a day. Tomorrow will be too windy to fly, so I will once again tune the engine and get the cowl back on.

Same as yesterday, another waste of time.

UPDATE (5/28/2020):  I took the plane out to the backyard bench and ran it up. Took about an hour to find decent settings. Still 4-cycles a bit at WOT, but now it has great RPM and Idle. I'll put the cowl back on, and next time I go out taker her with me to be disappointed again. There has to be something I have lost in tuning my engines for this to keep happening.

Well, that was a waste of time.

It began with having to solve a cat problem... Move one, the other two show up.

First flight with the Twinstar and her new nose gear went fine!

Started the Pulse XT60 RCGF-USA 26cc, and noticed the muffler shaking again, loose. Started to remove the engine to fix it, but without my bench tools it was going to be a painful and long process. Screw it, will fix it at home. Put her back in the car.

Second flight landing and the nose gear did not bend, but broke the forward bulkhead off. I saw this coming.

Quite the angle there.

Keith and Jason were tooling about, walked over before I left to say hi!

Spinner off, prop off, cowl off, engine off. Used J-B Weld as a gasket sealant and as a Locktite, having read it as a fix for this, and having it on hand. Sucker is snug. I also found a couple of lock washers, for whatever difference they make. I also found the throttle control arm nearly off, it's set screw held there by the choke arm! Jeez, this thing is shaking everything off. Standard blue Locktite, tight as I could make it. Engine back on, cowl back on, prop back on, spinner back on. Check pak charge. Ready to try again tomorrow. Really wasted time at the field.

Put the Twinstar aside in the shop, not in the mood for its foolishness. 

Think I need a second plane for tomorrow, since the helis are grounded until Spektrum fixes the software issue with heli DR/Expo. Hmmm... probably the Stik!

MX-Bach Tune Up

The MX-Bach was acting the fool last time I took her out to the field. All of my planes lately have had issues with idles that need to run high, and she was no exception. I have decreased the amount of oil to a bit thinner than 1:40, which I hope will help, and make for a lot less oil thrown on the fuse and wings. 

I noticed on inspection that the muffler has come off the cylinder. The Pulse XT 40 did this as well, seriously affecting how it ran, and its issues resolved with fixing it.. I will need to make this a regular preflight check. I think it is likely one of the reasons I had idle issues. Before I start screwing around with the needles I will start her tomorrow and see if this solves the issues.

One screw holding it on, oil sprayed all over the place, took a bit to clean up, and I couldn't get all the oil stain off the muffler.

Made a new gasket, or I should say, made a gasket because there wasn't one. Liberal Locktite.

The silencer had fallen off on the bench at the field, fortunately not in flight as it would be history. Whew... It popped out of the silicone having lost the securing wire tie. I used two this time.

Last time I took the MX-Bach up she was having idle issues. I had to bring her in hot, and she was floaty, after several attempts I finally brought her in and a foot off the ground killed the ignition. The same hand is used for the kill switch that I have on the elevator, soooo... I accidentally gave a little up elevator, she lifted up and stalled, dropped, and broke off an end of the CF landing gear. Thank goodness I have an exact replacement brand new hanging around in my shop! Some minor internal damage, mostly just cracked spars, easily fixed.

Took no time to drill the new holes and install. New pair of pants!

Messy during Man Working Time!

I installed a new tail wheel bracket because the carbon fiber one was getting too soft and wobbly. I purchased one for 120-150cc sized aircraft because, I don't know why. I should have gone with the smaller one, but I think I went with this one because the hardpoint on the fuse is shorter. I could have just cut the other one. It really doesn't matter, this one works fine. I wanted a metal one that would hold the vertical axle firmly, and this does the job. Since it's off center from the hinge point I thought of and tried a couple of different connections for the turn coupler, and ended up just using the rod method. To keep the turns from being too acute I had to put the rod connector pretty far aft. It works fine.

You can see the hardpoint on the right just fits on the tail of the fuselage. The tail wheel is now much more secure and sturdy. 

This is the kit that arrived. I know what each piece is for, but I don't understand that the silver handle screwed into the blue aluminum piece is. I removed the handle and used the blue part as the rod connector to the tail, as can be seen in the photo above this one, on the left. I was able to put an M2 bolt through it into the wood, so that is what I used it for. If anyone has any idea what that this is really for I am curious. Of course there were no directions/instructions...

I am now cleaning up the prop's paint a bit, and will reattach it tomorrow after re-balancing it and then see what I need to do to get the idle set right.