Are the dirt cheap transmiters causing interference?
12-29-2010, 02:27 PM
#1
Are the dirt cheap transmiters causing interference?
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
12-29-2010, 03:18 PM
#2
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: on_your_six
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the "park flyers" were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones "retuned" to transmit on 2.4GHz. I know they are not necessarily "legal" radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
12-29-2010, 05:49 PM
#3
Senior Member
RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: on_your_six We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky? I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
Flysky (aka Hobby King 2.4Ghz etc) TX and RX units - Blocked by Futaba FAAST that was V1,
RCModelreview also comments.
Note: V2 now updated to a hopping signal ex V2 review samesource.
"Well the old single-frequency non-agile DSSS system that was used in the V1 FlySky module/receiver (previously carrying the HobbyKing branding) has been replaced with the new frequency-hopping version. This ought to offer far more resistance to interference on the band and result in more reliable operation, except that... Now there's no satellite receiver, the system obviously relying on the constantly changing wavelength that frequency-hopping delivers, combined with the slightly higher gain of the sleeved dipole to compensate for that redundancy. "
Problem is a few see onlythe $ and, being themagic 2.4ghz, theymust therefore bebulletproof.
Note whilstthe cheapies may get blocked, they do not impact onthose withthe latest technology such as AFHSS and FASST.
Alan T.
Alan's Hobby, Model & RC FAQ Web Links
</dt>
12-29-2010, 07:56 PM
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RE: Are the dirt cheap transmiters causing interference?
We all have been spooked by the interference problems on 72MHZ.
Of course you can have interference on 2.4GHZ.
Its just very,very unlikely.
The reason the military uses SS is it is very hard to interfere with.
Of course you can have interference on 2.4GHZ.
Its just very,very unlikely.
The reason the military uses SS is it is very hard to interfere with.
12-30-2010, 03:13 AM
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RE: Are the dirt cheap transmiters causing interference?
Lol aussiesteve, flame suits on and set to hotter than hell.
How I see all this "2.4ghz has to much problems for me to use blah blah blah"
ANYthing that is transmitting a Radio signal weither it be 2.4ghz, 72mhz, 36mhz whatever is acceptible to Interference and it really doesn't matter if it's a $50 unit or a $2500 unit. You just simply can't guarantee a unit to be interference free.
A cheaper unit is probably going to be more acceptable to interference than the more expensive units because they don't have the power output.
Also the surrounding area (powerlines, trees etc) and the number of 2.4ghz units in the area is going to have effect. These days everything is 2.4ghz (etc Automatic Garage doors 2.4ghz) the chance of someone with one of these at the field pushing the button causing interference to your unit, very unlikely.
To answer on_your_six question, yes is quite possible for the spektrum unit to interfere with a cheaper unit.
The chance of a cheaper unit interfering with a spektrum, well it is still possible but unlikely.
At the field aussiesteve and myself fly at we still use a frequency board with (I think its 10 slots for 2.4ghz correct me if I'm wrong Steve) but with that said we also have a buggy club about 100mtr from the field, where alot of those guys are using 2.4ghz. We've had our fair share of both 36mhz and 2.4ghz going into lockout and you can 95% of the time guarantee it was pilot error, yet the radio unit's still get the blame (2.4ghz biggest error people make is to small a battery pack for the receiver and we all know what happens when 2.4ghz gets low on battery)
How I see all this "2.4ghz has to much problems for me to use blah blah blah"
ANYthing that is transmitting a Radio signal weither it be 2.4ghz, 72mhz, 36mhz whatever is acceptible to Interference and it really doesn't matter if it's a $50 unit or a $2500 unit. You just simply can't guarantee a unit to be interference free.
A cheaper unit is probably going to be more acceptable to interference than the more expensive units because they don't have the power output.
Also the surrounding area (powerlines, trees etc) and the number of 2.4ghz units in the area is going to have effect. These days everything is 2.4ghz (etc Automatic Garage doors 2.4ghz) the chance of someone with one of these at the field pushing the button causing interference to your unit, very unlikely.
To answer on_your_six question, yes is quite possible for the spektrum unit to interfere with a cheaper unit.
The chance of a cheaper unit interfering with a spektrum, well it is still possible but unlikely.
At the field aussiesteve and myself fly at we still use a frequency board with (I think its 10 slots for 2.4ghz correct me if I'm wrong Steve) but with that said we also have a buggy club about 100mtr from the field, where alot of those guys are using 2.4ghz. We've had our fair share of both 36mhz and 2.4ghz going into lockout and you can 95% of the time guarantee it was pilot error, yet the radio unit's still get the blame (2.4ghz biggest error people make is to small a battery pack for the receiver and we all know what happens when 2.4ghz gets low on battery)
01-02-2011, 03:07 AM
#6
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: aussiesteve
Ok, Flame suit on (I hope yours was on when you posted too).
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the ''park flyers'' were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones ''retuned'' to transmit on 2.4GHz. I know they are not necessarily ''legal'' radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
ORIGINAL: on_your_six
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the ''park flyers'' were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones ''retuned'' to transmit on 2.4GHz. I know they are not necessarily ''legal'' radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
72 MHz transmitters cannot be "retuned" to operate on 2.4 GHz.
If said 72 MHz transmitters utilize frequency modules, then 2.4 GHz modules probably could be fitted. This alone would not be "inferior" just because a new module was being used. The output power, type of modulation, whether fixed frequency or SS (spread spectrum) and accuracy of tuning/setup would all come into play.
This is not to say that some pretty pathetic R/C systems haven't been produced and sold world wide. It still pays to buy brand name R/C systems and to keep it properly serviced.
Ed Cregger
01-02-2011, 05:35 AM
#7
RE: Are the dirt cheap transmiters causing interference?
My son bought some 27 mhz cars on Ebay - these were the tiny but pricy z cars.
Wetried racing em with others and the interferrence was very noticable -
switching to 2.4 fixed the problem
I also refitted some cars with 2.4 which were formerly 72mhz
I did not use caps on the brushed motors but NO inteferrence or lockouts.
When I first got 2.4 DX6 in 2007 - we all tried all our std tricks to try and confound the then new 2.4 - Even flyin to 1900ft with this DX6 - (altimeter equipped model) using an on board 72 mhz for ail n elev- no problems - we just could not see it very well at that alatitude
lots more testing showed that lockouts were possible and the oibvious lack of understanding power and voltage was BIG problem here
(Icould not belive in this day and age , battery knowledge amongst modellers was so minimal)
anyway - with the spewing out of millions of 2.4 setups running micro models/toys etc., and many non modelling devices - I am amazed that interferrence problems are as low as they are.
Wetried racing em with others and the interferrence was very noticable -
switching to 2.4 fixed the problem
I also refitted some cars with 2.4 which were formerly 72mhz
I did not use caps on the brushed motors but NO inteferrence or lockouts.
When I first got 2.4 DX6 in 2007 - we all tried all our std tricks to try and confound the then new 2.4 - Even flyin to 1900ft with this DX6 - (altimeter equipped model) using an on board 72 mhz for ail n elev- no problems - we just could not see it very well at that alatitude
lots more testing showed that lockouts were possible and the oibvious lack of understanding power and voltage was BIG problem here
(Icould not belive in this day and age , battery knowledge amongst modellers was so minimal)
anyway - with the spewing out of millions of 2.4 setups running micro models/toys etc., and many non modelling devices - I am amazed that interferrence problems are as low as they are.
01-02-2011, 06:07 AM
#8
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RE: Are the dirt cheap transmiters causing interference?
I have been using the Spektrum 2.4Ghz module in my JR XP9303 for several years. I occasionally plug in my 72Mhz RF Module.
The only know shortcoming of using the Spektrum Module in the XP9303 as opposed to using the X9303 2.4 radio that does not have RF Modules is that the XP9303 has more Latency (takes longer for the servo to respond to the stick movement) than the X9303). There is also no Model Match when using the Spektrum Module. Other than that, the radios work identically.
The only know shortcoming of using the Spektrum Module in the XP9303 as opposed to using the X9303 2.4 radio that does not have RF Modules is that the XP9303 has more Latency (takes longer for the servo to respond to the stick movement) than the X9303). There is also no Model Match when using the Spektrum Module. Other than that, the radios work identically.
01-03-2011, 04:13 AM
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: rmh
My son bought some 27 mhz cars on Ebay - these were the tiny but pricy z cars.
Wetried racing em with others and the interferrence was very noticable -
switching to 2.4 fixed the problem
I also refitted some cars with 2.4 which were formerly 72mhz
I did not use caps on the brushed motors but NO inteferrence or lockouts.
When I first got 2.4 DX6 in 2007 - we all tried all our std tricks to try and confound the then new 2.4 - Even flyin to 1900ft with this DX6 - (altimeter equipped model) using an on board 72 mhz for ail n elev- no problems - we just could not see it very well at that alatitude
lots more testing showed that lockouts were possible and the oibvious lack of understanding power and voltage was BIG problem here
(Icould not belive in this day and age , battery knowledge amongst modellers was so minimal)
anyway - with the spewing out of millions of 2.4 setups running micro models/toys etc., and many non modelling devices - I am amazed that interferrence problems are as low as they are.
My son bought some 27 mhz cars on Ebay - these were the tiny but pricy z cars.
Wetried racing em with others and the interferrence was very noticable -
switching to 2.4 fixed the problem
I also refitted some cars with 2.4 which were formerly 72mhz
I did not use caps on the brushed motors but NO inteferrence or lockouts.
When I first got 2.4 DX6 in 2007 - we all tried all our std tricks to try and confound the then new 2.4 - Even flyin to 1900ft with this DX6 - (altimeter equipped model) using an on board 72 mhz for ail n elev- no problems - we just could not see it very well at that alatitude
lots more testing showed that lockouts were possible and the oibvious lack of understanding power and voltage was BIG problem here
(Icould not belive in this day and age , battery knowledge amongst modellers was so minimal)
anyway - with the spewing out of millions of 2.4 setups running micro models/toys etc., and many non modelling devices - I am amazed that interferrence problems are as low as they are.
It's the newer ppl to the hobby that don't know any better (considering a 4 cell pack is all you get when you buy a radio system) that will generally have lockouts with 2.4GHz because their 4 cell battery pack has gone flat or worse still has a crook cell.
I personally run a 8 cell battery pack running a voltage regulator, Five 10min flights and Iknow my batteries need a discharge/recharge.
Most of the Instructors at our field now tell any new fliers with 2.4GHz too throw away the 4 cell packs and get a 5 cell.
As for the micros/toys etc it really is quiet understandable. Most of those toys only lock on to 1 channel, where as the Radio systems we use Lock on to several. Also the power output of the toys radio system is simply nowhere near what our radio system put out, so if one of these toys happens to be locked on to the same channel as we are using it would get swamped, causing the toy to have interference not our Planes.
01-03-2011, 04:16 AM
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: rmh
My son bought some 27 mhz cars on Ebay - these were the tiny but pricy z cars.
Wetried racing em with others and the interferrence was very noticable -
switching to 2.4 fixed the problem
I also refitted some cars with 2.4 which were formerly 72mhz
I did not use caps on the brushed motors but NO inteferrence or lockouts.
When I first got 2.4 DX6 in 2007 - we all tried all our std tricks to try and confound the then new 2.4 - Even flyin to 1900ft with this DX6 - (altimeter equipped model) using an on board 72 mhz for ail n elev- no problems - we just could not see it very well at that alatitude
lots more testing showed that lockouts were possible and the oibvious lack of understanding power and voltage was BIG problem here
(Icould not belive in this day and age , battery knowledge amongst modellers was so minimal)
anyway - with the spewing out of millions of 2.4 setups running micro models/toys etc., and many non modelling devices - I am amazed that interferrence problems are as low as they are.
My son bought some 27 mhz cars on Ebay - these were the tiny but pricy z cars.
Wetried racing em with others and the interferrence was very noticable -
switching to 2.4 fixed the problem
I also refitted some cars with 2.4 which were formerly 72mhz
I did not use caps on the brushed motors but NO inteferrence or lockouts.
When I first got 2.4 DX6 in 2007 - we all tried all our std tricks to try and confound the then new 2.4 - Even flyin to 1900ft with this DX6 - (altimeter equipped model) using an on board 72 mhz for ail n elev- no problems - we just could not see it very well at that alatitude
lots more testing showed that lockouts were possible and the oibvious lack of understanding power and voltage was BIG problem here
(Icould not belive in this day and age , battery knowledge amongst modellers was so minimal)
anyway - with the spewing out of millions of 2.4 setups running micro models/toys etc., and many non modelling devices - I am amazed that interferrence problems are as low as they are.
It's the newer ppl to the hobby that don't know any better (considering a 4 cell pack is all you get when you buy a radio system) that will generally have lockouts with 2.4GHz because their 4 cell battery pack has gone flat or worse still has a crook cell.
I personally run a 8 cell battery pack running a voltage regulator, Five 10min flights and Iknow my batteries need a discharge/recharge.
Most of the Instructors at our field now tell any new fliers with 2.4GHz too throw away the 4 cell packs and get a 5 cell.
As for the micros/toys etc it really is quiet understandable. Most of those toys only lock on to 1 channel, where as the Radio systems we use Lock on to several. Also the power output of the toys radio system is simply nowhere near what our radio system put out, so if one of these toys happens to be locked on to the same channel as we are using it would get swamped, causing the toy to have interference not our Planes.
01-03-2011, 04:31 AM
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: NM2K
72 MHz transmitters cannot be "retuned" to operate on 2.4 GHz.
If said 72 MHz transmitters utilize frequency modules, then 2.4 GHz modules probably could be fitted. This alone would not be "inferior" just because a new module was being used. The output power, type of modulation, whether fixed frequency or SS (spread spectrum) and accuracy of tuning/setup would all come into play.
This is not to say that some pretty pathetic R/C systems haven't been produced and sold world wide. It still pays to buy brand name R/C systems and to keep it properly serviced.
Ed Cregger
ORIGINAL: aussiesteve
Ok, Flame suit on (I hope yours was on when you posted too).
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the ''park flyers'' were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones ''retuned'' to transmit on 2.4GHz. I know they are not necessarily ''legal'' radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
ORIGINAL: on_your_six
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the ''park flyers'' were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones ''retuned'' to transmit on 2.4GHz. I know they are not necessarily ''legal'' radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
72 MHz transmitters cannot be "retuned" to operate on 2.4 GHz.
If said 72 MHz transmitters utilize frequency modules, then 2.4 GHz modules probably could be fitted. This alone would not be "inferior" just because a new module was being used. The output power, type of modulation, whether fixed frequency or SS (spread spectrum) and accuracy of tuning/setup would all come into play.
This is not to say that some pretty pathetic R/C systems haven't been produced and sold world wide. It still pays to buy brand name R/C systems and to keep it properly serviced.
Ed Cregger
01-03-2011, 05:11 AM
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RE: Are the dirt cheap transmiters causing interference?
Hey mate
What I meant by "retuned" was a high level comment. They were not simply "adjusted" by the user, they left the factory adjusted to tranmsit in the 2.4 GHz range however all other functions were identical to a simple 72MHz unit - how frequency hopping, DSM, etc etc. It seems there was (perhaps is still) some transmitters (very el cheapo ones that were included with some park flyer packages) that had the transmitting modules installed at the factory to transmit in the 2.4 GHz band. I am not an electronics expert enough to explain it further. Those were the TX's to which I referred.
What I meant by "retuned" was a high level comment. They were not simply "adjusted" by the user, they left the factory adjusted to tranmsit in the 2.4 GHz range however all other functions were identical to a simple 72MHz unit - how frequency hopping, DSM, etc etc. It seems there was (perhaps is still) some transmitters (very el cheapo ones that were included with some park flyer packages) that had the transmitting modules installed at the factory to transmit in the 2.4 GHz band. I am not an electronics expert enough to explain it further. Those were the TX's to which I referred.
01-03-2011, 06:39 AM
#13
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RE: Are the dirt cheap transmiters causing interference?
There are many manufacturers of 2.4 RF Conversion Modules such as Futaba, Hitec, Spektrum, XPS, etc.. Most higher end RC Transmitters accept these modules. I use a Spektrum module in my JR XP9303. I believe they are well designed, reliable, and I have had no problems with it.
Are you talking about cheap radios that have had their innards replaced with 2.4 RF at the factory?
I'm sorry if I am misunderstanding your point.
Are you talking about cheap radios that have had their innards replaced with 2.4 RF at the factory?
I'm sorry if I am misunderstanding your point.
01-03-2011, 07:55 AM
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: BuschBarber
There are many manufacturers of 2.4 RF Conversion Modules such as Futaba, Hitec, Spektrum, XPS, etc.. Most higher end RC Transmitters accept these modules. I use a Spektrum module in my JR XP9303. I believe they are well designed, reliable, and I have had no problems with it.
Are you talking about cheap radios that have had their innards replaced with 2.4 RF at the factory?
I'm sorry if I am misunderstanding your point.
There are many manufacturers of 2.4 RF Conversion Modules such as Futaba, Hitec, Spektrum, XPS, etc.. Most higher end RC Transmitters accept these modules. I use a Spektrum module in my JR XP9303. I believe they are well designed, reliable, and I have had no problems with it.
Are you talking about cheap radios that have had their innards replaced with 2.4 RF at the factory?
I'm sorry if I am misunderstanding your point.
I'm not sure what the regulation are for the US etc but here in Australia all our Radio gear has to have a C Tick rating otherwise we risk not being covered by Insurance if (god forbid) anything happens.
But with the Parkflyer's it's pretty much anything goes.
01-03-2011, 09:34 AM
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RE: Are the dirt cheap transmiters causing interference?
ORIGINAL: PerthFlyer
Sorry to say (and I don't mean to step on any toes here) but they can and have been made to operate on 2.4GHz. I'm not sure what aussiesteve meant by returned (returned to supplier or just returned to service). But I got a couple of Radios from ebay to use on my sons parkflyers that where 72MHz, I simply put in a DIY 2.4GHz module.
ORIGINAL: NM2K
72 MHz transmitters cannot be ''retuned'' to operate on 2.4 GHz.
If said 72 MHz transmitters utilize frequency modules, then 2.4 GHz modules probably could be fitted. This alone would not be ''inferior'' just because a new module was being used. The output power, type of modulation, whether fixed frequency or SS (spread spectrum) and accuracy of tuning/setup would all come into play.
This is not to say that some pretty pathetic R/C systems haven't been produced and sold world wide. It still pays to buy brand name R/C systems and to keep it properly serviced.
Ed Cregger
ORIGINAL: aussiesteve
Ok, Flame suit on (I hope yours was on when you posted too).
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the ''park flyers'' were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones ''retuned'' to transmit on 2.4GHz. I know they are not necessarily ''legal'' radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
ORIGINAL: on_your_six
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
We had an incident today where a Spektrum transmitter (we think) knocked a much cheaper radio's plane down... 2.4ghz
With all the very inexpensive Chinese imported transmitters operating on 2.4 ghz, just what is the chance of one of these transmitters knocking my expensive plane out of the sky?
I am using AR6100, AR6200, AR7000, and JR921 with Dx6i and 9303 radios.
2.4 GHz can definitley encounter interference. - FACT.
How do I know this?
A couple of years ago, whilst living in China, I noticed how many of the ''park flyers'' were changing to be packaged to include 2.4G radios. Some of these were pretty much just the older 72MHz ones ''retuned'' to transmit on 2.4GHz. I know they are not necessarily ''legal'' radios in regulated places like the USA, UK and Australia but they were out there and some still are.
At the time, I was flying a JR / Spektrum conversion radio (9303 with a DSM2 conversion module) and was curious as to whether these could cause interference. I obtained a couple of those radios to try them - definitely caused interference on my control surfaces. The tests were carried out on the ground at a distance of about 10 metres with the respective TX's seperated by at least 3 metres from each other.
Of course when this was mentioned, I was told in no uncertain terms that it was not possible, could not happen and I was imagining it. Fact is it did happen.
So to answer your question - yes, it can happen. How likely it is to happen is another question altogether.
72 MHz transmitters cannot be ''retuned'' to operate on 2.4 GHz.
If said 72 MHz transmitters utilize frequency modules, then 2.4 GHz modules probably could be fitted. This alone would not be ''inferior'' just because a new module was being used. The output power, type of modulation, whether fixed frequency or SS (spread spectrum) and accuracy of tuning/setup would all come into play.
This is not to say that some pretty pathetic R/C systems haven't been produced and sold world wide. It still pays to buy brand name R/C systems and to keep it properly serviced.
Ed Cregger
We must be having a language problem on this forum. Actually, it is a miracle that we don't have more problems with language, considering all of the folks from different countries that participate here.
In technician parlance, "tuning" usually refers to adjusting an existing circuit board, not replacing a module tuned to one frequency/band with a module of another frequency/band. That is why I took issue with your statement.
Ed Cregger
