Lexmar

Just flew my first gasser over the weekend and have been getting intermittent radio glitches. I was told my install looks good but it would be best to upgrade my FM radio to a PCM. I was looking at the new Futaba Spread Spektrum system, would this be a better route glitch wise from the gassers ignition noise? Thanks very much!!!

Ialwayscrash

My Feedback: (106)

It is supposed to be but if you have a problem with regular receivers then you have a problem. I fly both PPM and PCM and never have a problem with either. What I am trying to say is find the problem and fix it and you won't have any trouble no matter which radio you use.
Crash

XJet

Ignition noise (which I assume is what your problem is) tends to drop off in intensity as you move up the frequency spectrum.

This means that it will be far less intense at 2.4GHz than it is at 72MHz.

However, there are other aspects to consider when weighing up whether to make that jump.

All the 2.4GHz stuff is pretty new (most isn't even released yet) and although initial field reports are good, we still haven't seen what happens when you get three or four *different* systems all competing for time-slots and frequencies in the 2.4GHz band.

The sensible thing to do would be to wait until the early adopters have encountered the problems (if there are any) so as to avoid jumping out fo the frying pan and straight into the fire.

GoeKeli

My Feedback: (18)

I have flown the xtremepowersystems module and receiver in my 2.6M composite arf extra for 2 long days. Not a glitch/lockout or anything. It is a magnitude better than PCM on my 9C. It is really sensitive and I had to create a new program and tone down throws and add expo. Not sure about spektrim of new futaba offerings. I'll be stickin with the extreme link for now and maybe get a new radio in a year after the parade of new stuff sorts it self out.

HTH

Joe

rmh

having jumped out of the fire -and into the frying pan . I am glad I did it .
There must be a downside to my DX2 system - so far -I have not found it.
from my 42% to my itsy bitsy 6 ounce foamy -
I remember my dad talking about the first gas buggies in their town------

BaldEagel

If you are getting glitches you have a problem with your installation, going to PCM or 2.4Ghz will only mask the problem not cure it, find out where you problem is and cure it before going any further, safety first always.

Mike

Zippi

My Feedback: (10)

Lexmar,

I totally agree with what is being said here. Find your problems and fix it. When I got my first gasser I had my share of glitches. I now run PPM and PCM and have not had any issues. Some guys will put a PPM in their new plane just to prove it out and then switch to PCM. Trying to find just where a glitch is coming form is some times a real chore. As far as the SS radio, I don't think I would run right out and buy one just because of your glitches. But, if your in the market for a new radio it would be something to consider. SS just came out and we flew many years without it so it's not like you have to have it. Just be more aware of who is on your channel at the field when your flying. We have a members roster that shows everyones channel and when I bought a new radio I would look for the lowest number of people on the channels. I just bought the new JR 7202 PCM radilo for my gasser so you see that SS is not a have to case for me. I'll wait til next year and then take a closer look at them. This gives them a little more time to get all the bugs worked out and bring the prices down a little as the market gets more flooded with SS radios. Just my 2cents worth.

BaldEagel

We don't just have a roster we use a peg board which you must hang your numbered frequency penant over the coresponding number on the board.

I have bit the bullet and bought a SS, someone has to have the equipment to iron out the bugs for everyone else, that's why I waited till now, you guys in the US have been using it for at least a year and I bought mine about 2 months ago, so far using it in an electric Kantana and a 2M Extra with a MVVS45 I have had no problems, reaching for piece of wood.

Mike

Brian Smith

My Feedback: (117)

I sold all my 72 stuff and went to Two DX7s on SS.. I was having channel issues at my local field, and almost got shot down by a person on my channel at a big flyin even though I had the pin.. Enough of that for me. 50 flights later, in 4 different bigger gas models and I could not be more pleased. I was at a flyin last sat with 3 different SS radios flying and within sight of busy RT40 in TN.. All was clean and perfect as expected.. I can now run a metal cable to my throttle servo, and metel to metal contacts in my model have given me "NO" glitches or problems.. Color me one happy SS user.. Brian Smith

Lexmar

I would love to be able to find where the isssue is. I have people at the club take a look at the plane but was told everything looks good except for the FM radio I am using. I can get 75 feet away from the plane with the antenna down while the engine is running, the glitch happens only when the plane is in flight, scary. Thanks for everyones input, appreciat it

Rcpilot

My Feedback: (78)

75 feet? Antenna down? Engine running? Perfect?

Thats not a range check.

A range check with the antenna down is rock solid performance out to 200+ feet. I don't even THINK about flying until I can get a 300' range check, antenna down, with my engine running.

If your glitching at 75' on the range check--you got major problems. The problem should be about as obvious as a fart in church.

You got metal too metal contact someplace? How is your igniiton? Where are the batteries? Where is the RX? Crashed servos? Crashed RX? Crashed crystal? Antenna running next to the servo extensions? Igntion switch, battery, unit too close to the RX battery, switch, servos? Old servos? Used servo extensions?

Josey Wales

My Feedback: (61)

What radio are you using and what does you manual say is an acceptable range ? Did you try a different RX ?

BaldEagel

On the Futaba Zap you must range check with the base section of the aerial extended the wipers inside the case do not make contact until you extend the base section, transmitting without extending this section overloads the RF section and can blow your modual.

Mike

NM2K

My Feedback: (14)

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With the present level of technology in our old 27, 50, 53 and 72 MHz rigs, you cannot expect to have an absolutely solid link every time you fly, even if your model installation is absolutely perfect. There are seasonal conditions that permit competing signals from distant places to reach your receiver, regardless of the type of modulation. When a competing signal enters your receiver's front end with sufficient amplitude, your system will experience a glitch. There is simply no way to avoid this from happening. Fortunately, most of the time we fly glitch free.

Our receivers are also subject to being glitched by multipath reception. That is, your signal from the Tx bounces off a nearby metal object and arrives a tad later than the original signal, confusing the decoder section of your receiver. This too is normal and is something that we have to live with. This same thing occurs whether your system is running PPM or PCM. With PPM (FM) we can see the glitch. With PCM the system blocks the codes that do not pass the CRC check. In both situations you have no control during that segment of time (usually very small).

The problem with this conversation is that I do not know what you are calling a glitch. It may be just a winggle now and then, or your model may snap roll, or do any number of things. More info from you would be nice.

Intermittant switch contacts, improperly bonded servo leads or pc board connections in the airborne pack or the Tx could be causing your glitches. If the radio is glitching badly, I would send it back for servicing. At least then you have confirmed that the problem is in your installation and not faulty equipment. It could be that your ignition engine has absolutely nothing to do with your current problem.

Back when all of this gas engine flying began, all we had to work with were AM R/C systems and we flew them quite successfully. Don't be in such a hurry to blame PPM (FM) and jump to PCM. PCM hides problems.

Would you be better off on 2.4 GHz? I can't say for sure, but I just bought two 2.4 GHz systems myself (Spektrum), so we shall see. Good luck.


Ed Cregger

ljones5000

My Feedback: (2)

Joe, what differences did you see after converting your 9C? I read a little about the EX Systems but didn't understand if your display still works as always. There was something about a display that plugs into the 9C antenna slot. Where is the antenna for the transmitter?

I'm interested in whatever you can tell me because this sounds really too good to be true! I'd love to convert mine if it all works the way they say.

Larry

Lexmar

Thanks guys. I am using a Futaba 4EX, nothing fancy. The manual stated 20 to 30 paces so I would think the 25 paces that I got while the engine is running is okay. When the glitching happens in flight, I can hear the engine revving up by itself and maybe some slight unwanted movements in the control surfaces. This is an all new plane, except for the RX and TX, TX is good as it flies well with other planes that I have. Because my RX battery is mounted towards the back of the plane for balance, the RX antenna wire ran parralel with the batt wire inside the fuse. I will re-route the RX wire outside th fuselage. The ignition eqpt. is mounted in the front of the plane and radio stuff behind. I will also switch to a known RX that works and see what happens. Any ideas why it tests fine in the ground and glitches only in flight? Thanks again gents!!!

Josey Wales

My Feedback: (61)

One time I got some glitches in the air from a loose wheel collar..didnt show up on the ground

captinjohn

Josey Wales: Did you get a glitch or your radio system? Hey....you still quick with those side Irons!!!!!! Best Regards Capt,n

Josey Wales

My Feedback: (61)

Im pretty sure it was the plane...that time anyway! [8D]


Whooped 'em again!

captinjohn

Josey Wales.......YOUR OK!!!!!!! Capt,n

k8bvj

Very interesting Brian, I guess 2.4 ghz is worth a try after being on 6 mtrs all these yrs...hi. What do you think of Futaba's 6ex rig?

K8BVJ (since 1956)

Brian Smith

My Feedback: (117)

Howdy Friend
I flew on 50 MHZ for years, I quit when some companies made equipment and others I had been using did not, then I bought a couple airtronics visions that gave me problems on 00 and 09.. Got by for a couple years on 07. I then went to 72.. Been on 72 about 4 years..
I could not be more pleased with my DX7's.. Honest injun !! I have not seen the Fut 6 ch yet..73.. CUL. Brian

Forgues Research

My Feedback: (7)

Always, always, always , fix the problem first, don't mask it.

I love my Multiplex 4000 but I would like to try the 2.4 spread spectrum, but they don't offer them so I don't what I'm going to do

Any suggestions???


Roger

AmpAce

That's just the point! With the 2.4 Gig systems, you don't have to go through all of that miserable stuff! About a year ago I was trying to get an 80" electric Super Cub into the air, but had some kind of a weird power system interference going with my FM system. Tried and tried to find the problem, changed most everything out, but still couldn't get a reliable range check over about 20 feet, with the motor running.

Finally gave up in despair and bought a SS DX6 system and installed it. Nary a glitch since! Why beat your head against a wall when you don't have to? It's easy to say that something is wrong when a new plane produces glitching, but the causes of these things can be very hard to find, especially nowdays with more and more electronic equipment tending to get put in our planes. There does not necessarily have to be something really "wrong" for a signal to be generated that will mess up your FM radio.

Here where I fly, I have been shot down at least 3 times by errant, unknown signals. I don't know if it was the Ham operator down the road, some kid turning on his "ready-to-fly" transmitter, or something else, but the result was the same, three dead airplanes!

For my money, I've bought my last FM radio. 2.4 ghz is obviously going to be the wave of the future, and if it gives my airplanes a better chance of survival, then it is in my future too! They are eventually going to revolutionize R/C flight, with plane to ground feedback possible, for things such a cylinder head temp, fuel level, airspeed, altitude, flight pack voltage, you name it.

I'm not sure which brand I would buy just now. My DX6 has worked perfectly well on a plane much larger than it was intended for, and now there are long range outfits from SS, Futaba, JR, and soon to be Hi-Tec, I suspect. I've read many good things about the Extremelink system too, and since it has now been announced, we should soon have some good user reports. My advice would be to hold off, if you can, until more experience is gained with the 2.4 systems, to see which one looks like it will work best for you, but if you need one now, buy with confidence. After all, the prices are not that much more than for our FM systems, and I think for what we get they are a real bargain.

AmpAce

Josey Wales

My Feedback: (61)

Really the point is you still have the problem its just the 2.4 is hiding it....for now anyway...usually it comes back to bite you but hopefully it wont..When I goto 2.4 I will still range check with my ppm rx however..I kn ow if I cant get 20' then there is a major issue..

I think a lot of people will leave out the range check when they use the 2.4 which is a mistake IMO