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[seand]

But you would not get lockout - because a US Rx is the same as a UK Rx and the US setup works ok in the US. Therefore a US Tx with a US or UK Rx should work perfectly ok in the US or the UK.

Reread my post above.

If your using a UK set and the person next to you is using a US higher power set, there is the chance that your signal gets 'drowned out' by there higher power set. Your RX would loose it's signal and lockout.

I'm with Ronp on this one, the US sets all fly together and it isn't raining aircraft there, why should it here?

Because all their sets are transmitting on the same power output. I bet if you tried to fly with a lower powered UK set in the states you get problems. We don't have any problems at my site because everyone is using UK sets. If I was flying my £2000 heli around and someone wanted to fly next to me with a more powerful Tx, what do you think I should do  Carry on flying and hope nothing will happen. I don't think so.

Just for information and to put things into perspective:

In the UK, the 35MHz band is exclusively for Airborne Model control with an output of 100mW.

The 2.4GHz band is not. It is classed as open to ISM applications. (Industrial, Scientific and Medical).

The 2.4GHz model control band is 2.4000GHz to 2.4835GHz @ 100mW (ERP).
The 2.4GHz Amateur Radio band is 2.4000GHz to 2.4500GHz @ 400W (PEP).

This means a flying field could be in line of sight of an Amateur Mobile transmitter (On top of a hill), radiating 400W in the 2.4GHz band. If the mobile TX is feeding a directional antenna, the output power could be 400W x the Antenna gain.

This is just one user of 'our' 2.4GHz band - how many others are there?

As a Licensed Radio Amateur, would I be legally allowed to operate a home built, uncertified 2.4GHz transmitter for model control? Would my BMFA insurance be valid? Would my fellow fliers form a Lynching party?

I will let you know.

Ron

But the Spektrum/JR system locks onto 2 seperate frequencies within the 2.4ghz band and is less susceptible to outside interference.

You have some valid points and I don't forsee these 'issues' being resolved anytime soon.

If you were to make your own 2.4 Tx and use it for model control then this is not the same as using it for communications purposes surely. Your Amatuer Radio LIcence covers you for communications purposes only, doesn't it? You would not be covered by the BMFA, as you are not if you use an imported set. At my field you would not be allowed to fly.

[admin]

Reread my post above.

If your using a UK set and the person next to you is using a US higher power set, there is the chance that your signal gets 'drowned out' by there higher power set. Your RX would loose it's signal and lockout.

So tell me, whats the difference when a fellow fliers model is near your Tx and he's stood 100 yards away, what about the Nats, you have models flown on several flight lines, the situation would be the same it's own signal getting weak and another signal getting strong.

Seems the same scenario to me.

Because all their sets are transmitting on the same power output. I bet if you tried to fly with a lower powered UK set in the states you get problems. We don't have any problems at my site because everyone is using UK sets.

How do you know there would be problems with a non uk set?...... YOU DON'T

If I was flying my £2000 heli around and someone wanted to fly next to me with a more powerful Tx, what do you think I should do  Carry on flying and hope nothing will happen. I don't think so.

How do you know there isn't a much more powerful data network right next to you, amateur radio just down the road or someone in the next field or elsewhere in the locality with a foreign 2.4GHz system? you dont.

Just for information and to put things into perspective:

In the UK, the 35MHz band is exclusively for Airborne Model control with an output of 100mW.

The 2.4GHz band is not. It is classed as open to ISM applications. (Industrial, Scientific and Medical).

The 2.4GHz model control band is 2.4000GHz to 2.4835GHz @ 100mW (ERP).
The 2.4GHz Amateur Radio band is 2.4000GHz to 2.4500GHz @ 400W (PEP).

This means a flying field could be in line of sight of an Amateur Mobile transmitter (On top of a hill), radiating 400W in the 2.4GHz band. If the mobile TX is feeding a directional antenna, the output power could be 400W x the Antenna gain.

This is just one user of 'our' 2.4GHz band - how many others are there?

Exactly, the CE marking is blown out of all proportion, FWIW I do have a UK legal DSX9, I don't agree with being ripped off but there we go. Do I have confidence in 2.4? Well 2 jets, both worth over £3500 are on 2.4.

J

[seand]

So tell me, whats the difference when a fellow fliers model is near your Tx and he's stood 100 yards away, what about the Nats, you have models flown on several flight lines, the situation would be the same it's own signal getting weak and another signal getting strong.

Seems the same scenario to me.

At the Nats, all the 2.4ghz sets are transmitting on the same power output, and remember that they are all on different frequencies, within the 2.4ghz band. My concern would be flying beside someone using a higher power output Tx, and the possibility of the higher power signal swamping the lower power signal. This could in effect reduce the range of the lower power set and cause a lockout.

How do you know there would be problems with a non uk set?...... YOU DON'T

Correct I don't, but I wouldn't want to try it either and I think it would be highly irresponsible of our committee to allow the use of non approved sets.

How do you know there isn't a much more powerful data network right next to you, amateur radio just down the road or someone in the next field or elsewhere in the locality with a foreign 2.4GHz system? you dont.

That is not the same scenario as I posted. What I said was if someone at our site wanted to use a higher powered set, I wouldn't fly. At the sites I fly, which is all around the country during the competition season, there has nether been an issue with a 2.4Ghz set. We don't know what other 2.4Ghz systems or users there are around us, but it has proven to be the best and most secure radio link for model flying, we have ever had.

[admin]

At the Nats, all the 2.4ghz sets are transmitting on the same power output, and remember that they are all on different frequencies, within the 2.4ghz band. My concern would be flying beside someone using a higher power output Tx, and the possibility of the higher power signal swamping the lower power signal.

You miss the point completely. What happens to your radio signal as you get further away?..... it gets weaker, the sceario I described was one of having your model a long way away from your tx and close to another. This would give a similar situation to 2 Tx's together with differing power outputs.

This could in effect reduce the range of the lower power set and cause a lockout.

Why would it do that? It would be on different channels OR in the case of FASST jumping around all of the channels.

I think it would be highly irresponsible of our committee to allow the use of non approved sets.

I agree with you on this one, I feel the regulations are wrong and thats made people somewhat paranoid as were seeing here. It won't rain aeroplanes and heli's with a non CE marked set in operation. Assan equipment is working perfectly alright along with DSM2 and FASST and that only outputs 10mW on a single channel IIRC.

That is not the same scenario as I posted. What I said was if someone at our site wanted to use a higher powered set, I wouldn't fly. At the sites I fly, which is all around the country during the competition season, there has nether been an issue with a 2.4Ghz set. We don't know what other 2.4Ghz systems or users there are around us, but it has proven to be the best and most secure radio link for model flying, we have ever had.

Thats because of the security of data on the link, there are hundreds of applixcations using 2.4GHz, from door bells to wireless networks, non of them affect our RC control systems which is testimony to the integrity of the link. Consider teh DSM2 system, picks 2 channels and uses them for the flight, Spektrum operated succesfully 43 transmitters and model control was fine, how so? only 80 channels available.......

J

[Mark]

Interesting Thread guys for the most part....

Futaba sets are all UK legal because they made there's pump out MW the same across the board... (well they all have CE marks anyway  )

JR and spektrum use the higher MW allowed in other parts of the world ?

Please feel free to point out if I am i'm wrong!!!

The JR DSX9 or 12 simple you buy an import set you take the module ebay it for the USA or HK, BUY the UK spec module and have a decent tranny at a decent price not JR's silly price's.

Also what about these other 2.4ghz modules appearing where you do internal mods to your trannys how does that work ?

[admin]

Please feel free to point out if I am i'm wrong!!!

Youre wrong

The JR DSX9 or 12 simple you buy an import set you take the module ebay it for the USA or HK, BUY the UK spec module and have a decent tranny at a decent price not JR's silly price's.

Nice idea BUT, it doesn't have a module and the casing is a dead giveaway i.e. it doesn't have MacG's badge.

Also what about these other 2.4ghz modules appearing where you do internal mods to your trannys how does that work ?

A very grey area seemingly.

J

[ronp]

Fitting a 2.4 GHz module to an existing tranny, (according to Manufactures instruction of course), should be ok for CE compliance. Modifying the module like moving the Antenna connector would I expect, invalidate the CE certification as well as the Warranty.

Should a club member be allowed to use a modified module? From what has been said before, maybe not.

Ron

[Mark]

Please feel free to point out if I am i'm wrong!!!

Youre wrong

The JR DSX9 or 12 simple you buy an import set you take the module ebay it for the USA or HK, BUY the UK spec module and have a decent tranny at a decent price not JR's silly price's.

Nice idea BUT, it doesn't have a module and the casing is a dead giveaway i.e. it doesn't have MacG's badge.

Also what about these other 2.4ghz modules appearing where you do internal mods to your trannys how does that work ?

A very grey area seemingly.

J

[ronp]

The CE certification requires amongst others, a susceptibility test.

In the case of a 2.4GHz receiver, the test would fire a wide spectrum of RF energy at the Unit under test while it is running. Any deviation from its specified operation would be noted.  This test  would therefore simulate a second transmitter in close proximity. Question is, did the Rx get swamped and lock out?

Why have manufacturers not published their receivers’ susceptibility results?
I think it should be part of their specification.

Ron

[Marian]

Contact them and ask for the info.Quote the freedom of information act.

[admin]

Contact them and ask for the info.Quote the freedom of information act.

I think that applies to personal information only.

J

[Marian]

Contact them and ask for the info.Quote the freedom of information act.

I think that applies to personal information only.

J

I thought it applied to any information?

[keybaud]

Sorry for the necro, but there haven't been a lot of posts and this one was still on the front page near the top..

Contact them and ask for the info.Quote the freedom of information act.

I think you'll find that the FOIA act is for information held by the government and their representative departments, not private companies.

Some companies will provide you with copies of the CE Technical File on request, detailing the results of their testing, but they are not legally bound to do so. If there is an issue with a CE'd piece of equipment, the purchaser is meant to raise the issue with the CE Directive's authority, who then request the CE Technical File from the seller and assess the criteria used to assess conformance.

It is worth noting that an item has to carry a CE label to be sold in Europe, but if you have bought an item without a CE label from outside Europe it does not automatically mean it is illegal to use in Europe. The lack of a CE mark just means that you don't know if it is legal or not to use. i.e. You ought to do some research before using it.