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Author Topic: JR / Macgregor and Spektrum - a statement please re possible legislation changes  (Read 43662 times)

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Offline propeak

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I'm in the process of having to replace my Futaba FF9 as its been playing up lately. With all this going on, i'm now reluctant to upgrade to my chosen tx, the new DX8. What would most people do with the DSM2 saga, bite the bullet and get one or opt for something else.

Steve
The DX8 might be a brand new transmitter and regardless of what happens next year it uses DSM2 which is now old technology, would you go out and buy a five year old mobile phone?,
thousands of people including myself have been using DSM2 with no problems but i personally won't be investing anymore hard cash in it,
there are now plenty of systems on the market which are far more up to date so have a good look round and study the forums before you spend your hard earned cash.


Offline Steve J

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I really don't understand some of the comments in this topic.

DSM2 is a proven system backed up by Horizon Hobby's exemplary customer care. It works.

I will be amazed if EN 300 328 is changed in a way that makes any existing system non-compliant. Horizon don't seem to be behaving as if they think that they won't be selling DSM2 systems in the EU in the near future. In fact they are releasing a transmitter that appears to be targeted at the central European market later this year.

Spektrum and JR going their separate ways is irrelevant as far as most users are concerned. The DX8 is going to kill the DX7 and I suspect that making the DX7 was where JR made money out of the deal. Are DX7's still being made ? I suspect not. The DX10T will hit sales of the DSX9. The people who are not going to be impressed by JR are the dealers with stocks of DSX9's and DSX12's.

Just my 2p worth.

Steve

Offline Steve J

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The DX8 might be a brand new transmitter and regardless of what happens next year it uses DSM2 which is now old technology, would you go out and buy a five year old mobile phone?,

Most mobile 'phones are GSM which is lot older than DSM2....

Steve


Offline CF-FZG

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I really don't understand some of the comments in this topic.

Neither do I Steve $%&

You've got leccy with his usual panicking about the subject and now others have jumped on his bandwagon :banghead:
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Offline leccyflyer

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Let's try not to get personal eh?

There's a good chap.
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Offline Theaton56

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Guys,


It does not matter what the TG11 rewrite of 300-328 ends up as.

Should DSM2 be no longer a valid system at 100mW after October 2011, if you have DSM2 based equipment, you are still allowed to use it.  All it means is that you cannot buy a new transmitter with DSM2.

Perhaps DSMJ was designed by Spektrum/JR not just for Japan but knowing how devious HH can be, perhaps as a contigency plan ??

JR did NOT WANT to use Spektrum's DSM but HAD to for legal reasons. Now that the agreement seems to be expired (or perhaps broken  $%& ), JR are now free to continue with their own system.

I think we are panicking over a small minor hiccup.

 :xx   :''

Offline bullfrog_sc

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My worry is I spend £300 now on the dx8 then in 12months I'm unable to get any dsm2 rx's. Don't really fancy having to upgrade in 12mths time due to not being able to get any rx's.

Steve

Offline leccyflyer

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My worry is I spend £300 now on the dx8 then in 12months I'm unable to get any dsm2 rx's. Don't really fancy having to upgrade in 12mths time due to not being able to get any rx's.

Steve

There have been plenty of folks who have said that you will still be able t buy DSM2 receivers, no matter what happens. The logic is that it's only the TX that is affected, since the regulations are different for 10mW transmission and 100Mw transmission. Since those folks consider the RX is irrelevant in terms of the transmission output their guess is that DSM2 receivers will continue to be sold. Plus, of course you'd be able to continue to use any ones you already had, including transmitters. Still sounds like a potential dead end to me though.
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Offline CF-FZG

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My worry is I spend £300 now on the dx8 then in 12months I'm unable to get any dsm2 rx's. Don't really fancy having to upgrade in 12mths time due to not being able to get any rx's.

Why do you say that?  There's no logical reason to think that, as if DSM/DSM2 is banned restricted to 10mW in europe you'll still be able to buy the Rxs as they won't be affected :af
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Offline bullfrog_sc

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My thinking was that if they stopped selling the dsm2 transmitters then they would stop selling receivers for the same system. Sorry if I'm completely wrong but that was just my ill-informed logic.
Steve
« Last Edit: August 29, 2010, 23:00:54 PM by bullfrog_sc »

Offline leccyflyer

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My thinking was that if they stopped selling the dsm2 transmitters then they would stop selling receivers for the same system. Sorry if I'm completely wrong but that was just my ill-informed logic.
Steve

It's not beyond the realms of possibility that there would be no new models of DSM2 receivers, if the transmitters are phased out.
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Offline CF-FZG

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My thinking was that if they stopped selling the dsm2 transmitters then they would stop selling receivers for the same system. Sorry if I'm completely wrong but that was just my ill-informed logic.
Steve

Your asuming that if the EU restricted DSM/DSM2 power output to 10mW then the system would die in the water.  However, the European market is small fry compared to the main Spektrum market, which is the US, then you have Australasia, the Far East (excepting Japan), Africa etc.  Having said that, even if the EU laws regulations are changed, we have been told the legacy systems would still be allowed, and there would still be a huge market in Europe for DSM/DSM2 Rxs, even if it means going to the US or elsewhere for the Rxs :af  (but I don't see HH stopping the sale of the Rxs in Europe for quite a while, as long as there's a market for them)

It's not beyond the realms of possibility that there would be no new models of DSM2 receivers, if the transmitters are phased out.

You're forgetting the 'rest of the world' market :''

Maybe I was wrong to say 'panicking' in a previous post, when I could well have said 'scaremongering' :banghead:


Mark
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Offline leccyflyer

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Your asuming that if the EU restricted DSM/DSM2 power output to 10mW then the system would die in the water.  However, the European market is small fry compared to the main Spektrum market, which is the US, then you have Australasia, the Far East (excepting Japan), Africa etc.  Having said that, even if the EU laws regulations are changed, we have been told the legacy systems would still be allowed, and there would still be a huge market in Europe for DSM/DSM2 Rxs, even if it means going to the US or elsewhere for the Rxs :af  (but I don't see HH stopping the sale of the Rxs in Europe for quite a while, as long as there's a market for them)

You're forgetting the 'rest of the world' market :''

Maybe I was wrong to say 'panicking' in a previous post, when I could well have said 'scaremongering' :banghead:


Mark

No, I'm not forgetting the rest of the world market. I'd consider carefully whether HH would go through the process of CE testing for those receivers, whilst presumably simultaneously selling whatever new system that they might adopt in the event of the decision going against them.

As regards scaremongering, it seems to me that the point of this thread is to seek clarification  from the manufacturers as to what their intentions are in the event that DSM2 becomes restricted to 10mw under the rregulations. It has produced a quick result in that, with the release of the statement made by Macman, and that must surely be of major interest to any user of JR DSM-2 equipment. The thread starter is to be commended for that, as is MacMan for his posting of the forthcoming JR switch of systems.
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Offline Barrye

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The real issue is that the second hand value of your TX plummets (just look at 35MHz - on BMFA 9x2 +5RX's £240 vs  DSX9 Tx only £250)  and if you want to change your TX in the future you have to change all your RX's as well. I have over 10 DSM2 Rx's so that would be really expensive!


Barry

Offline FlyinBrian

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My thinking was that if they stopped selling the dsm2 transmitters then they would stop selling receivers for the same system. Sorry if I'm completely wrong but that was just my ill-informed logic.
Steve

I suppose, assuming the customer base is big enough, DSM2 rx will still be available as Horizon / Spectrum will sell it if its in demand and legal.  There are DSM2 rx available from Hobby King now and if it was not viable there would not be 3rd party equipment being made.

It just pees me off when manufacturers continue to sell stuff they are about to make obsolescent
Basic Research is what I do - when I don't know what I'm doing!.

Offline nasa_steve

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would it not be a good idea for JR to seek to write a firmware upgrade for the Spektrum recievers to allow those that supported them when they went to DSM2 in the first place to move onto the new JR system that way they would retain some of their customer base. surely that would be a way of appeasing their current customers and possibly a way forwards to gain some more customers maybe??
steve
nasa_steve

Offline Alan Smithie

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Aside from the legal/IPR issues it may not be physically possible - the spectrum hardware may not be sufficiently compatible.

PDR
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Offline FrankS

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We seem to be assuming here that JR are stopping using DSM2 due to upcoming EU regulations, but if you look at it from a worldwide basis JR probably regretted jumping in with another manufacturer so quickly, especially if it then excluded them from the entry level sets. But maybe at the time they thought that the DSM2 system was the way to go and development of the alternative would take too long and they didn't want to do a Multiplex and be late to the market.

Offline Theaton56

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IF JR wanted to get into the 2.4GHz market, they HAD to use Spektrums DSM/DSM2.  They had their own system but that had to be put to one side.

As I said, DSMJ was a stopgap measure for their home market as the Japanese authorities deemed the DSM based system as being DSSS and therefore limited to 10mW.

Here in the EU, the regulations were not as cut and dried as the Japanese and DSM was accepted as a FHSS based system.


Offline stuey

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If anyone is interested, here are my thoughts having read the thread.
When I started reading about this, I assumed that if the EU ruled against the current DSM/DSM2 equipment anyone with it may have to stop using it all together. If you continued to use it you could be in breach of the law, club regs, insurance policies etc. This would be most unfortunate for anyone that had invested in the kit, like myself with a Spektrum module in my Futaba FF9 and possibly 10 rx's.
Now having read that any existing equipment will still be allowed to be used (if the rules change), I am now relaxed about it. Whilst my module still works, can be repaired or replaced, I can use all of the equipment I have bought for many years to come. If a situation arises where new TX devices cannot be sold with DSM2, there are still a lot of people that have them, and Rx's are still going to be available as existing stock or from other world markets. I would have thought that the easiest way to make the manufacturers stop providing RX's, would be if everyone panics and tries to sell their DSM2 kit and destroy the market. Who would want to buy the glut of DSM2 equipment anyway if it is doomed? Keep hold of it and get your moneys worth I reckon.
Spektrum kit may have to change in the future for some reason, but I think there is plenty of life left in it yet.

Offline danishpasty

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Where does this leave the new JR 11X zero DSM2 tranny. Up on blocks before its even left the showroom. I was recently thinking about upgrading my trusty DX7 and looked at a cheap DSX 9. Glad I didn't take the plunge. Like lots of others on here, I think there will be plenty of DSM2 RX's available for years to come even if the TX are no more( but I hope it doesn't come to that  :xx).
Cheers, Rob.

Offline CF-FZG

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I would have thought that the easiest way to make the manufacturers stop providing RX's, would be if everyone panics and tries to sell their DSM2 kit and destroy the market. Who would want to buy the glut of DSM2 equipment anyway if it is doomed?

A very good point :af  as to the second part, I'd be up for some cheap Rxs ;)
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Offline taximan

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Hang on a minute, is DSM2 definitely going to be illegal to buy from next year or is it all speculation?

Offline Alan Smithie

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-3db S:N on DSM2??

I suspect this is another example of Spectrum's rather imaginative approach to marketing.

 :''

PDR
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Offline Alan Smithie

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I reported some months ago that using the scanner on my Weatronics system, it shows my DX7 always chose channels that were half the available band apart, so for example it would choose channel 1 and 41, or 10 and 50 and so on.  It never varied from that, it never chose 2 adjacent channels or even nearby channels.

I meant to come back on this Harry - are you saying that it *always* selects pairs that are 40 channels apart? Is there any way you could check against another DSM2 Tx to find out if they all use a 40-channel pair or if it varies from one Tx to another? If they all use the same spacing then this would concern me, because it seems to remove some of the potential robustness from the system. On switch-on the Tx selects one of 40 possible channel sets, and if two did happen to select the same pair (because the second Tx was temporarily masked from the first) then BOTH of its chosen channels would conflict and they would be relying solely on the low duty-cycle for continued communication, which would be rather risky!

PDR
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Offline CF-FZG

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Hang on a minute, is DSM2 definitely going to be illegal to buy from next year or is it all speculation?

Speculation :af
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Offline Kambalunga

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On switch-on the Tx selects one of 40 possible channel sets, and if two did happen to select the same pair (because the second Tx was temporarily masked from the first) then BOTH of its chosen channels would conflict and they would be relying solely on the low duty-cycle for continued communication, which would be rather risky!

PDR

This is not a problem for DSSS. DSM2 use 49 different spreadingcodes and 32bit GUIDs.
If an undesired transmitter transmits on the same channel but with a different PN sequence (or no sequence at all), the de-spreading process results in no processing gain for that signal. This effect is the basis for the code division multiple access (CDMA) property of DSSS, which allows multiple transmitters to share the same channel.

CYWUSB6935: Forty-nine spreading codes selected for optimal performance (Gold codes) are supported across 78 1-MHz channels yielding a theoretical spectral capacity of 3822 channels.

Offline Alan Smithie

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...which is fine for a data network where the "clogging" simply causes slower data rates and a few dropped packets, but in real-time control applications it causes paradoxes.

But my real point was simply surprise at the fixed channel seperation - it reduces the options to 40 potyential channel pairs rather than 1600 (402) potential channel pairs.

PDR
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Offline steamysheep

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Fascinating thread. I wish I could add more to the dialogue than "welcome back Pete, we missed you" and my own position.

I am one of the early adopters, fed up with waiting for my channel at flyins, and then getting shot down, and went for the DX7 when everyone was crying "2.4g that's the Work of Satin". Now nearly three years later I am satisfied with that choice..

I never keep a radio for more than three years and am nervous about having "old" receivers in my planes so my oldest Rx would be sold on before it's 5 years old. Both TX and Rx get a lot of use and I value the airframes more than the radio.

I have recently changed from the DX7 to the DSX9 as part of the "keeping the radio new" policy. That will give me another three years when it'll be time to change out most of my receivers and get another new tranny too.

Hopefully all this debate will done and dusted by then.

BUT, with modern technology I think we will be looking at the next major development then and will be pondering X.X delivering super duper downlink capability that will make the next generation obsolescent by 2014 anyway!

So I feel for the people who take a long term view on radio; and when I retire that will be me too. Wonder what the debate be around in 2018 to 2023? I'll probably go back to 35mucky cycles..
Keeping my chin up!

Offline stuey

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Unfortunately its going to be hard to take a long term view if you ask me. The whole 2.4gig concept is still maturing and new innovations coming out, so picking the right horse to bet on will be hard. Every manufacturer wants their system to be the best new thing around, trying to woo the crowds onto their side. At least on 35meg it is a mature system, with cross compatability between manufacturers giving us more choice.
Until I am told it is illegal to use my DSM2 kit and what I have still works, I see no reason to change. I do however understand that people have reservations about buying it new now. But, Spektrum seem to be putting a lot into their new 8 channel radio, if they were to abandon customers in a year or so's time that WOULD be very bad for their image, and would suffer a great deal afterwards.

Offline HarryC

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I meant to come back on this Harry - are you saying that it *always* selects pairs that are 40 channels apart?

I wouldn't worry about it Pete, as we don't know it's channel choosing procedure.  When I tested mine, it was always an environment where there was only one other fixed channel transmitter, my home wifi, showing on the scanner.  The wifi was a low power spread wide across several channels and didn't prevent the DX7 from sometimes choosing channels the wifi was using, the DX7 showing much taller, narrower spikes.  It could be that the DX7 rules are (and these are pure speculation for illustrative purposes);
1. Scan all band. Pick 2 free channels that are 40 channels apart.  If none, go to 2.
2. pick 2 free channels that are 39 or 41 channels apart.  if none go to 3.
3. pick 2 free channels that are 38 or 42 channels apart.  and so on and on.

That would allow for mine always picking 2 channels half the band apart because there was nothing else using the band, and would allow for it to vary that if conditions required it, even picking 2 adjacent channels in extremis.

Offline Theaton56

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Quote
Where does this leave the new JR 11X zero DSM2 tranny

The current version is as you know modular (unless you bought one outside the EU), the CE approved version has not been released yet.

I'll be honest here, I do not know if the DSX11 is going to be DSM2 or DMSS....  I will try and find out.  If it is DSM2 then (to me) it's a bloody weird business model to follow !


Offline Lplus

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Hi Gordon,  yes the 11X DSm2 module fits any normal 5 pin module based Tx.

I tested the DSMJ and DSM2 modules on my 9XII. 

Does that include the old 388 and 347?  If so there'd still an upgrade path to JR DMSS for me too, if JR bring out that type of module.

What!?  so, I like them and I'm a skinflint - so what  ;D

Offline Kambalunga

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Macman - and that is exactly the problem.
The distributors / manufacturers could prevent wild speculation by an assurance they won't leave DSM/DSM2 users without a future come Oct 2011. A few "what if" scenearios could be run through.  

Best case scenario would be for JR/Speki to state as soon as possible that they do or do not have an upgrade path if DSM2 is outlawed failure to do so causes the speculation you refer to.


Horizon Hobby abou the DSM2 conformity.
http://translate.google.de/translate?u=http%3A%2F%2Fwww.rc-network.de%2Fforum%2Fshowpost.php%3Fp%3D1904763%26postcount%3D1&sl=de&tl=en&hl=&ie=UTF-8
http://www.rc-network.de/forum/showpost.php?p=1904763&postcount=1


The BNetzA about DSM2 and the validated conformity of DSM2.

http://translate.google.de/translate?u=http%3A%2F%2Fwww.rc-network.de%2Fforum%2Fshowthread.php%3Ft%3D216192&sl=de&tl=en&hl=&ie=UTF-8
http://www.rc-network.de/forum/showthread.php?t=216192

We should not forget, Horizon Hobby is a ETSI member.

Offline pchristy

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Forgive my late arrival at this topic! I've only just discovered this forum, but I see someone has kindly copied a message I posted on another forum at the head of this thread.

First a disclaimer: I don't work for JR, Futaba, MacGregors, RipMax, or anyone else, though I do know a number of people who work or who have worked there (Hi Mac-Man!). I am NOT privy to any secrets they may have! The following is based on some knowledge and some speculation, but I believe it to be an accurate summary of the situation (warts and all)!

The EU VERY CLEARLY stated at the meeting in Brussels over a year ago that they have NO INTENTION of banning or power restricting DSM systems. It simply is NOT going to happen. Why not? Because every single wireless router on sale in PC World, Currys, etc and made by every big network manufacturer uses a variant of DSM! They do NOT frequency hop!

If a ban such as has been suggested in this thread were implemented, the howl of outrage from the computer industry would be heard on Mars!

2.4 GHz in an "industrial dustbin" band - like 27 MHz and 459 MHz. It is not exclusively for RC. Nor is it exclusively for computer networks. Any regulations specified will be for ALL users, not just for RC or computers. There will be no way of drawing up different specs for different applications!

I know this band seems very important to us - and it is. But remember, we are minnows compared to the computer industry! If the EU banned DSM it would immediately and effectively ban every single existing computer network and router in the country! Its simply ISN'T going to happen!

What may well happen is that there will be a shift in alliances in the commercial world, and the new JR sets may well be the first symptom of that. Futaba are a giant in the electronics industry, making not just RC sets, but components for a wide range of electronics gadgets. The chances are that the fluorescent display on the front of your DVD player is made by Futaba!

From what I have been able to gather, when Spektrum came out with their 2.4 GHz sets, it caught the Japanese completely flat-footed! They hadn't seen it coming! Futaba already had industrial 2.4 GHz systems, so it didn't take them long to modify them for model control use. JR are nothing like as big as Futaba. I seriously doubt that they had enough in-house talent to design a system from scratch once they realised how big it was going to be. I'm guessing that the only way they could get a system on the market quickly enough to keep up with Futaba was to do a deal with Spektrum. This would have been aided by the fact that their US importer was Horizon, who also own Spektrum! The US is their biggest market, so this scenario makes a lot of sense!

I would guess that in the intervening time, they've been busy recruiting 2.4 GHz engineers to design their own system. It must have been quite embarrassing for them to have to admit that they could only compete by "buying in" an existing design, and saving face is very big in Japan! It looks like they are now ready to start testing the water with their own design system. Interestingly, it looks like they are - initially at least - keeping to the bottom end of the market with the new system, leaving the top end stuff as DSM2. No doubt once the system is proven, they will begin migrating their top end stuff over too, but I would expect that to be at least a couple of years away yet.

So no, DSM2 is not going to vanish over-night. Nor is there any likelyhood that it will be subject to power or any other restrictions in the redrafted regulations.

This has all to do with corporate politics and FUD, and very little to do with any technical arguments!

--
Pete Christy

"No matter how hard you push the envelope, it will still be stationery!"
--
Pete
 "No matter how much you push the envelope, it'll still be stationery."

Offline Didg

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Just found out about this...... subscribed.

Offline pchristy

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Some further reading:

If you want to know what the situation REALLY is, you have to go to the horses mouth, ie: Ofcom

http://stakeholders.ofcom.org.uk/binaries/spectrum/spectrum-policy-area/spectrum-management/research-guidelines-tech-info/interface-requirements/mso9140.pdf

This link takes you to the document which is Ofcoms implementation of ETS 300 328, the EU regs governing 2.4 GHz.

The important bit (for us) is table 2.1 at the top of page 6, which I recreate in text form here:

                                         Table 2.1: Minimum Equipment Requirements
                      Lower Frequency Range                      Upper Frequency Range               
                           2400 MHz                                               2483.5 MHz

Minimum aggregate bit rate               250 kBit/s

Modulation                      Frequency hopping, direct sequence or other forms of spread spectrum modulation

Effective Radiated Power                  -10 dBW (100 mW)

Power Density                    Frequency hopping-10 dBW (100 mW) per 100 kHz
                              Other forms of spread spectrum modulation-20 dBW (10 mW) per 1 MHz


As you can clearly see, direct sequence (DSM) is permitted just as much as frequency hopping.

BOTH are permitted an erp of 100mW.

What most people misinterpret is the last two lines (power density)

Trying to put this in laymans terms, this is saying you can either put your pint of beer in a tall, thin glass (100mW per 100KHz), or a short, fat one (10mW per MHz). In either case it is still a pint of beer (100mW erp)!

DON'T confuse erp with spectral density. This is where the confusion arises!

I think this cleary demonstrates that there is NO regulation against DSM - nor is there likely to be.

Any changes JR may (or may not) be making have all to do with corporate politics and contracts, and nothing to do with technical merit!

Just relax and buy what works best for you. DO NOT be put off by all the FUD and mis-information currently doing the rounds!
--
Pete
 "No matter how much you push the envelope, it'll still be stationery."

Offline Lplus

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Hmm, fascinating.  So FHSS can put all its 100mW power into a 100KHz band whilst others must spread their 100mW over at least 10MHz?

As I haven't invested a lot in 2.4, and still have plenty of 35meg I'm not averse to using cheap stuff for now and upgrading to JR when(or if) suitable modules are available.

Offline pchristy

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Hmm, fascinating.  So FHSS can put all its 100mW power into a 100KHz band whilst others must spread their 100mW over at least 10MHz?

That's over 1 MHz, not 10 MHz!

As I said, don't read too much into that power density figure. The thing that's really important is signal to noise ratio (S/N). This is what ultimately limits your range / performance.

You can improve your S/N ratio either by using more power density, or by using more bandwidth. If you look at the above figures, you will see that DSM uses 10 times the bandwidth, but the power density is 10 times less, so you end up in exactly the same place!

In addition, DSM is perfectly capable of recovering a signal from below the noise floor - something that logic tells you is impossible! I was given a good analogy of how this works a while back: If you go to Heathrow to pick up your son/daughter/spouse, you will have no trouble picking him/her (the signal) out despite the crowds around him/her (the noise). This is because you know what you are looking for, and can pick it out from the surrounding mush. So a DSM receiver can pluck a signal from noise that may actually be greater than the signal!

Yes, it makes my brain hurt as well......!!
--
Pete
 "No matter how much you push the envelope, it'll still be stationery."

Offline Lplus

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That's over 1 MHz, not 10 MHz!

You can improve your S/N ratio either by using more power density, or by using more bandwidth. If you look at the above figures, you will see that DSM uses 10 times the bandwidth, but the power density is 10 times less, so you end up in exactly the same place!

Sorry, I understand now.


 

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