Surprising source of radio interference
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RE: Surprising source of radio interference
......and one more thing. The sensor wire doesn't run across the magneto, as I stated in my original post. It is, however, very near the magneto when it is attached to the engine.
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RE: Surprising source of radio interference
ORIGINAL: ScottMcM
......and one more thing. The sensor wire doesn't run across the magneto, as I stated in my original post. It is, however, very near the magneto when it is attached to the engine.
......and one more thing. The sensor wire doesn't run across the magneto, as I stated in my original post. It is, however, very near the magneto when it is attached to the engine.
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RE: Surprising source of radio interference
ORIGINAL: Flypaper 2
Both planes I mentioned above flew fine prior to and after the problems were solved, with no more glitches, so there were no servo problems.
Both planes I mentioned above flew fine prior to and after the problems were solved, with no more glitches, so there were no servo problems.
Try this: Turn on your receiver without the transmitter. Then run the engine with a non resistor plug.
If your servos glitch you will know you have servo problems. With the transmitter off your receiver will be in fail safe and not putting out any pulses.
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RE: Surprising source of radio interference
If it is near the magneto and it is unshielded wire you can get induced voltage in any wire. Moving magnetic field + wire = generator.
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RE: Surprising source of radio interference
ORIGINAL: dirtybird
Do as Andy suggested. Check to make sure the temp sensor does not have an intermittant short to the engine.
ORIGINAL: ScottMcM
......and one more thing. The sensor wire doesn't run across the magneto, as I stated in my original post. It is, however, very near the magneto when it is attached to the engine.
......and one more thing. The sensor wire doesn't run across the magneto, as I stated in my original post. It is, however, very near the magneto when it is attached to the engine.
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RE: Surprising source of radio interference
ORIGINAL: JL1
If it is near the magneto and it is unshielded wire you can get induced voltage in any wire. Moving magnetic field + wire = generator.
If it is near the magneto and it is unshielded wire you can get induced voltage in any wire. Moving magnetic field + wire = generator.
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RE: Surprising source of radio interference
ORIGINAL: Flypaper 2
I'm not here to argue. Just stating a couple of problems and the proper fixes. They're both working fine.
I'm not here to argue. Just stating a couple of problems and the proper fixes. They're both working fine.
You think you have fixed your problem but the odds are that you haven't and at some later time it might just bite you.
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RE: Surprising source of radio interference
ORIGINAL: Bill Vargas
On the heat sensor(thermocouple) ,,, are you getting funny temp readings? (sure sounds like a grounding issue)
BV
On the heat sensor(thermocouple) ,,, are you getting funny temp readings? (sure sounds like a grounding issue)
BV
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RE: Surprising source of radio interference
Scott, I would try some snap on ferrite cores from Radio Shack or electronic stores on that lead coming from the engine. In most RF issues those will help to eliminate the RF issue at hand. Do a search on the web,,, they come in all different shapes and wire sizes too, etc.
BV
BV
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RE: Surprising source of radio interference
ORIGINAL: Bill Vargas
Scott, I would try some snap on ferrite cores from Radio Shack or electronic stores on that lead coming from the engine. In most RF issues those will help to eliminate the RF issue at hand. Do a search on the web,,, they come in all different shapes and wire sizes too, etc.
BV
Scott, I would try some snap on ferrite cores from Radio Shack or electronic stores on that lead coming from the engine. In most RF issues those will help to eliminate the RF issue at hand. Do a search on the web,,, they come in all different shapes and wire sizes too, etc.
BV
You are correct, IMHO
I am an RF guy from WAY back.......and the interference you get from ANY ignition system is Next level bad![:@]
The entire noise floor goes way up on a Spectrum Analyzer to show this…
It will make most anything “Glitchâ€â€¦..or malfunction.
I like to use these wherever I can in Gas planes…
http://www.jrradios.com/Products/Def...ProdID=JRPA028
Very affordable insurance...
And I would move everything away from the magneto and make sure the entire ignition system is well shielded and there is no shorting out any of the wires…
Make sure plug cap is tight and use resistor plug.
In general I stay away from Magneto’s but by no means is electronic ignition any better……ignition pulses are high energy interference that can even cause damage to sensitive electronics such as telemetry modules or Rx units……
Be careful with the ferrites not to “Mask†the problem……I try to get everything working without them and then use them to help insure low noise levels in the system.
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RE: Surprising source of radio interference
Of all the replies your the only one who has a viable solution to the problem. Loose cap plugs and non resistor type sparkplugs also are problamatic. It appears that 2.4ghz technology has it share of problems and the only thing it has solved is waiting for the pin. When I started in this hobby I flew ppm FM and experienced all types of RF both internal and external and than came pcm and most if not all issues evaporated. RF was still around but the new designed receivers filtered out must interference. Bottom line is dollars you are willing to spend on electronics and nothing more. Example of this would be in extension leads. Those made of pure cooper wire or a clone made in China which uses tin.
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RE: Surprising source of radio interference
Are you sure the noise is coming through the 2.4 receiver and not from the servo leads or servo electronics picking up low frequency noise?
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RE: Surprising source of radio interference
2.4 is much better than 72 for rejecting noise. A buddy and I built a Sea Fury Reno Racer quite a few yrs ago for the big rc jobs to race in Quebec but the race was canceled about a month before the dateline. This one weighed 60 lbs with a Quadra 200cc racing engine. About 20 servos in it all together. Was plagued with servo glitches. Did fly about 3 times but decided it was to dangerous. We gave it to his son to tinker with as he's an avid RCer too. This summer he brought it up for our IMAA do with a 2.4 radio in it. Not a whimper out of it with no other goodies to cancel the noise than the 2.4 radio itself. Great to see it fly again.
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RE: Surprising source of radio interference
Really, I was involved behind the scenes in Reno racing before 2.4ghz was introduced and they all flew on 72mhz. The only radios that failed were Hitec and I'm not talking about their servos. I'll say it again its all about dollars invested and how your electronics are installed. I mentioned leads in my last post and discovered this due to what I though were malfunctioning elevator servos. Our company built an erial target with a fuselage length of sixteen feet. the length of the elevator servo leads were about ten feet. The problem was traced to a voltage drop because of the long leads. We made our own leads using pure cooper strands. I don't remeber the gauge but it sloved the problem. Most models don't no anything about electronics and there operation and blame the equipment as being the culprit when in reality it's there own stupidity. Nothing is perfect and you usually pay for what you get. Is an O.S. engine the same as an ASP?
#43
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RE: Surprising source of radio interference
Point well made. Output transmitter power is the name of the game. Our company would order FM ppm receivers matched to assigned military frequencies. With these receivers and a linear amplifier powering our modified RC transmitters we never experienced loss of signal or jamming. Remeber our commercial transmitter are rated at .75 watts of output power. The linears we used went from 10W to 50W. You might say we captured the receiver.
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RE: Surprising source of radio interference
ORIGINAL: ChuckA
Are you sure the noise is coming through the 2.4 receiver and not from the servo leads or servo electronics picking up low frequency noise?
Are you sure the noise is coming through the 2.4 receiver and not from the servo leads or servo electronics picking up low frequency noise?
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RE: Surprising source of radio interference
We could have solved the problems if the race had of been put on, with choke coils, rewiring etc., but after the races were canceled it was a moot point, as the nearest races were at Reno and not worth the drive. Would have made a good show plane but that's about all. The newcomers don't realize how lucky we are with 2.4
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RE: Surprising source of radio interference
ORIGINAL: flycatch
Tell that to those who have suffered for ''brown outs''.
Tell that to those who have suffered for ''brown outs''.
2.4 is the best thing that has happened to this hobby and I have flown 72Mhz for 33 years.
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RE: Surprising source of radio interference
Tell your story to those who have lost their models to this new technology. I have and still am flying 72mhz but I don' use PPM only pcm dual conversion receivers. In the old days of ppm I experienced a lot of problems and airborne failures so I'm not advocating the continued use of 72mhz. The reality of 2.4ghz is simply cost for the manufacture nothing more. The other advantage is no longer waiting for your frequency to clear. The average modeler is not willing to pay $200 USD for a DC PCM receiver but they will pay $70 USD for a 2.4ghz receiver. I'm staying on 72mhz until it becomes illegal.
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RE: Surprising source of radio interference
I bought the first DX6 locally when they first came out and never had a brownout. As Rich says"use enough batt power and you wont have trouble". Chucked in planes from overheated ESCs and such,but nothing to blame on the radio. No trouble with the DX7. Had troubles with the DX8 when they first came out with the ensueing teething problems but they have been solved and it's now working great. Been at RC for the last 50 yrs, starting out with escapements. Try one of them for reliability when you your rubber band runs out. Now that's a brown out.
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RE: Surprising source of radio interference
ORIGINAL: flycatch
Tell your story to those who have lost their models to this new technology. I have and still am flying 72mhz but I don' use PPM only pcm dual conversion receivers. In the old days of ppm I experienced a lot of problems and airborne failures so I'm not advocating the continued use of 72mhz. The reality of 2.4ghz is simply cost for the manufacture nothing more. The other advantage is no longer waiting for your frequency to clear. The average modeler is not willing to pay $200 USD for a DC PCM receiver but they will pay $70 USD for a 2.4ghz receiver. I'm staying on 72mhz until it becomes illegal.
Tell your story to those who have lost their models to this new technology. I have and still am flying 72mhz but I don' use PPM only pcm dual conversion receivers. In the old days of ppm I experienced a lot of problems and airborne failures so I'm not advocating the continued use of 72mhz. The reality of 2.4ghz is simply cost for the manufacture nothing more. The other advantage is no longer waiting for your frequency to clear. The average modeler is not willing to pay $200 USD for a DC PCM receiver but they will pay $70 USD for a 2.4ghz receiver. I'm staying on 72mhz until it becomes illegal.
I travel to meets all around New York State, the surrounding states, and Canada. We are not experiencing any significant problems with 2.4. Perhaps our part of the country is immune from the gremlins that affect 2.4 users elsewhere. I am on RCU many times per day as well as occasionally on FG and RCG. I have read many of the threads regarding RC Radios. I am personal friends with some pilots who compete nationally at the highest levels. None of them are turning away from 2.4.
I have spent years tracking down RF problems that glitched 72Mhz radios. For us, 2.4 has made most of that unnecessary, not to mention freedom from ShootDowns and no need for a Frequency Pin.
I am sorry for others who still have issues with 2.4, but we are not seeing any problems here. The only thing keeping anyone from getting rid of 72 altogether is just the cost to convert.