captinjohn

pictures & video.....+1

stevegauth30

Maiden flight went perfectly. Very un eventfull. Sorry I forgot the camera but I'll bring it tomorrow to our picnic/fun fly and get some footage. Thanks again for the help.

av8tor1977

My Feedback: (6)

COOL! Congrats! I'm guessing you had plenty of power for that Speedster, right?

AV8TOR

dirtybird

My Feedback: (5)

Have you tried such atest? I believe those "documented facts" could be explained if the document er looked further..
I say this: the only way you are going to affect a 2.4 system is cover the entire band with noise and then the receiver will simply go into failsafe.-not cause servo to hunt.
OK Trucker I have made 1 more post.
Goobye

av8tor1977

My Feedback: (6)

I guess you missed my post about the interference I documented. With a Hitec Aurora 9 2.4 system. It's not the first time I encountered problems with interference on 2.4 gig. No matter what your tests show, real world results have shown different.

And I'm no electronics genius but I believe electrical sparks pretty much cover the entire band of RF.

AV8TOR

All Day Dan

My Feedback: (5)

Don’t leave now dirtybird we’re trying to save one of your planes. I fly 1 ½ hours a session once a week. If I live another ten years I will need 780 hours of interference free flying. Your tests have been run for a few minutes. That’s not long enough for me. In order to do this right, you would have to analyze the spectrum of the spark and test it in an anechoic chamber and analyze the susceptibility of your receiver to any RF and then do the same testing. Some manufacturers may be doing it but it is very expensive. Your best bet is to just avoid the possibility in the first place and follow good RF techniques. Dan.

dirtybird

My Feedback: (5)

Iam not going to leave.It was truckracer that said he was going to leave.
According to most experts a spark has frequencies all over the band. Even to light. So if you can see it then you dont need a spectrum analyser to examine it..
I dont fly my airplanes in an anechoic chamber. Do you? I have tested a few satellites in one of those though.
susceptibility of the receiver? I believe you mean sensitivity. I have tested mine. Its -104dbm according to my tests.
I use good RF techniques. I just dont use those developed in the 70's on an antique system

Truckracer

My Feedback: (19)

Read closer! I never said I was going to leave, just said I wasn't going to discuss the 2.4 GHz ignition interference issue. Already said all I want to say about that. Still here though.

A person probably shouldn't say forever though as none of us rcer's can keep our opinions to ourselves that long!

dirtybird

My Feedback: (5)

I am going to set up a test.
I will drive the cheapie ignition system from my function generator ,equipped with a non resistor spark plug. I will sit it next two two receivers,one XPS the other Tatanis. I can transmit to both receivers simultaneously using the Taranis. .I will connect a servo to each receiver, one digital one analog.
I will also connect my oscilloscope to channel 8 on one receiver and program the Taranis to put the rudder on channel 8.
I will take pictures but I am unable to make a movie.
Any other suggestions?...

Truckracer

My Feedback: (19)

While maintaining my no discussion policy, I might still suggest you try one test with the plug threaded in an engine but just leave the cap loose where it doesn't make good contact with the plug on the shield side. You might also add some long servo leads, etc. to duplicate a real installation in a large airplane.

dirtybird

My Feedback: (5)

I can easily add long servo leads but I can't simulate a loose cap without running an engine. I really don't want to do that as it would likely destroy the Hall sensor..
I think some of the loose cap interference issues wer caused by miss fireing of the engine that caused an increase in vibration. This could cause a servo to hunt. Make the cap secure and the motor smoothes out and the excess vibration goes away. Then the servo stops hunting and you think it was interference

Truckracer

My Feedback: (19)

Well if the test isn't authentic, it really isn't valid then is it? it can be done, you're the engineer, figure it out!

Sounds like you're just rationalizing to me trying to validate your point without proving it.

dirtybird

My Feedback: (5)

The reason a loose cap bothered the old 72 systems is it caused a spark to occur outside of the engine. As an.engineer I can safely tell you tyere is no difference between a plug spark spark and one that occurs in the cap.
I think you are just looking for an excuse to say my tests are not valid. That is your privilege. It does lower my opinion of you however..

Truckracer

My Feedback: (19)

Yes, as described, I believe your tests may not be valid. They may validate your point of view but not answer the greater question of whether a 2.4 GHz. radio "system" can be interfered with by spark energy. By system, i mean both the 2.4 GHz front end / radio link and the low frequency back end that includes all the wiring, servos, switches, batteries and decoder / processor part of the receiver.

I could easily set up a controlled test that would simulate the loose cap condition. But then, I'm not the one wanting or needing validation of statements I have made. I'm satisfied with what I have seen in the real world and that is "good enough" for me.

av8tor1977

My Feedback: (6)

In the case of my 50cc Extra that I mentioned in an earlier post, it wasn't just a random servo wiggle. When I got in front of the plane with the radio, so that the bad plug/cap was between the transmitter and the airplane electronics, ALL of the servos went into wild oscillations. And the engine was running perfectly; no excess vibration.

Once again, Hitec Aurora 9 system, 2.4, Hitec 9 channel receiver, and all high dollar Hitec servos in the plane. The interference was real, I didn't dream about it.... (But now I wish I had a movie of it!)

AV8TOR

dirtybird

My Feedback: (5)

OK I figured out how to simulate your test. I have an Edge 540 set up with the receivers like I proposed. I can just take tyhe spark plug out of the DLE 30 on it and spin it with the starter. Then i can loosen the cap as you ask.
Unfortunately I will have to go out to the field and have others help me. Since I just got out of the hospital with a pacemaker implant I will not be able to drive for awhile.
But you seem to have a closed mind maybe there is no point in it.

Truckracer

My Feedback: (19)

Yes, you are correct, on this subject my mind is probably well decided as like av8tor1977, I have seen the problem happen first hand and on more than one occasion. The engine was running perfectly at the time with no excessive vibrations. The only symptom was the servos moving out of control.

dirtybird, I hope you understand that I mean no disrespect to you in this matter. Quite the contrary actually! I treat this just as I would if we were carrying on a conversation in person. I believe we just share an honest difference of opinion on how spark energy can affect our radio systems and once again emphasizing the word systems. Frankly, I believe you are as closed minded about the matter as I am.

If good installation practices are followed, 99+% of the time, there is no problem! So few people really care much about this anyway. Just an FOG and FOG in training discussing something nobody else cares about.

dirtybird

My Feedback: (5)

Yes my mind is closed on this subject. I spent several months checking out the command system for the Iridium spacecrafts That system was very similar to are systems. the only difference is it is on 3.0GHZ and they change the code every day. I satisfied myself that noise simply will not cause interference to such a system.
The problem you have is you see a result and you chock it up to interference. There are many other things that could cause the problem. You need to eliminate those first.
I have decided there is no further test I could perform that will prove what I say to you
I have given you a simple test you could perform yourself and you have chosen to ignore it.
So I will depart this thread.

speedracerntrixie

My Feedback: (29)

Correct me if I am wrong but I think a function generator puts out cleaner DC voltage then batteries? Especially batteries that are in our environment?

Even so I personally have not seen a single 2.4 lockout that could be linked directly to an ignition. I have seen an ignition spill enough RF to be picked up by the servo leads. No matter what side of the fence you are on with this topic, common sense should prevail. Does, twisted wires, non metallic throttle pushrods, component separation, ect have any adverse affects on the radio system? Of course not, there is some evidence that they all may be a benifit so why not err on the safe side and stick with the old school tried and true methods? Granted it would be different if we were putting things into space and we wanted to farther the tech but reality we are playing with toy airplanes that have the potential to do people harm.

Truckracer

My Feedback: (19)

Back on post # 30, I acknowledged that spark interference was probably not going to happen on a 2.4 GHz RF link. I don't know what more I can say about that. Further, I harped that the problem could exist in the rest of the radio system (not the RF section .... how can I say it clearer) and that I have witnessed servo jitters and random servo movements when plug caps are left loose and from other ignition issues. Even when pointing out these issues, you refuse to look at the picture as a whole and continue to insist that a 2.4 GHz radio can not be interfered with .... and only seem to want to look at the RF portion of the system .... which I acknowledge probably is immune to spark interference. There is more to a radio system than the RF section!

I really should not have come back to this thread as it really is like banging ones head against the wall and no, it doesn't feel very good.

ahicks

My Feedback: (2)

Sounds like you guys need to get out and do some flying? -Al

stevegauth30

That's all I'm doing. I had an issue, asked a question, got an answer, and fixed the problem. Now, I fly. I learned a lot in the mean time and I thank you all for that. Maybe I should have worded the original question differently and not called it " interference" but I am no expert on the matter and am not ashamed to say that. Truth be told, I know just about as much as most who fly these. I turn on the radio, turn on the RX, either it works or it doesn't. It now works flawlessly and my question has been answered so, with that, I say good by and happy landings.

Truckracer

My Feedback: (19)

It was raining here the last couple of days so I had lots of time on my hands .... to get in trouble I guess!

Flying today and the truck is loaded and ready to go.

stevegauth30

So, I'm really not sure what to make of this, except that the ignition is suspect. I have about 20 awesome flights now, all without any sign of the previous issue. Then, at startup for flight 21, the engine starts surging at idle. Fine at WOT. So, I'm scratching my head, thinking maybe the low speed needle got bumped or something, and I notice it. The same thing as before. Servos jumping or hunting, or what ever it's called. Weather it's the problem or not, I am ordering a new ignition. This one looks old, so I'm figuring that's the problem. Just glad it didn't start doing that in the air. Without going into debate, any thoughts?

acerc

I guess, given the history here, I would say "Start it up and start jiggling wires and connectors". Could be another one has worked loose.