Spektrum DX6 & 7

Henry Farley · Post by **Henry Farley** » 13 Jul 2007, 13:46

When the class rules were originally written we all knew what a receiver was. Spektrum DX6 & 7 use two receivers so how do they fit with class rules permitting only one?
Just to complicate the isue, DX6 has its two receivers in a single case while the DX7 has separate cases.

Andy Stevenson · Post by **Andy Stevenson** » 13 Jul 2007, 20:44

Hi Henry

Spektrum DX6 & 7 use two receivers so how do they fit with class rules permitting only one?

Excellent question!

Youâ€™re quite right of course, D.2.4(a)(1) specifies one receiver.

To the letter of the rule neither is class legal. There may be an argument for proposing a class rule change to alter â€œOne Receiverâ€

Hiljoball · Post by **Hiljoball** » 13 Jul 2007, 21:21

My reading of the DX7 documentation is that there are two receiver circuits which function together as one receiver to improve signal descrimination. That the manufacturer has chosen to place the receiver circuits into two connected boxes is just a packaging and antenea orientation issue.

I see nothing wrong with this.

Andy Stevenson · Post by **Andy Stevenson** » 13 Jul 2007, 21:54

From the Spektrum website [http://www.spektrumrc.com/Products/Defa ... ID=SPM2710]

The AR7000 Dual Receiver

Comprised of a compact main receiver that is linked to an even smaller satellite receiver by a 6â€

RoyL · Post by **RoyL** » 13 Jul 2007, 23:23

As I understand the system, the satellite "receiver" can not operate on its own. Also, there is only a single set of connections for the servos and battery on the main "receiver" and none on the satellite. Finally, Spektrum itself call the project a "receiver". In my opinion, therefore, this is clearly a single device that would be acceptable within the meaning of the current IOM Rule.

Lester · Post by **Lester** » 15 Jul 2007, 22:55

Seems a clear case for an official request for an interpretation, and if that goes against the Spektrum system, a (nearly simultaneous) request for a class rule change would probably find unanimous assent.

Barry Fox CAN262 · Post by **Barry Fox CAN262** » 16 Jul 2007, 21:55

A phone call would likely clear it up but my guess is that if you try to buy either of the pieces to the two piece receiver you will be told that they are not available as separate piece, only as a single unit/part number/functioning accessory. But maybe a clarification is needed to cover the "two channel" receivers as the twin antenna style of technology is also in use by Futaba and it would appear that it is likely the direction any other manufacturer will go as well.

We have already made allowance for the Tx by recognizing that the receiver in these systems does send some info back to the Tx and by not requiring a ball on the end of the antenna so this is just house keeping kind of stuff as I see it.

RoyL · Post by **RoyL** » 17 Jul 2007, 04:38

I don' t think that this is an issue that needs an immediate technical interpretation. The Spektrum receiver is a single unit. It is sold and described as a "receiver". The second box, the "satellite". can not function on its own and can not be purchased on its own. There is only a single set of servo connections for the two boxes and a single battery and switch connection. The servos are fed a single set of commands. This product is plain and simple a single receiver.

As to the Futaba spread spectrum systems, currently the receiver is a single box.

Now if somebody thinks that the rules as written allowing only one receiver should be changed. that's a different story. (Frankly, I can't see why someone would want more than one receiver but I don't see any performance advantage either.) The AGM is coming up and if some NCA wants to make a rule change proposal so be it.

jeolla · Post by **jeolla** » 17 Jul 2007, 22:47

This debate might include a more precise definition concerning "The rudder control unit........(C.5.3 (a))
Some gyros are now sold as a kit with a servo and might soon be integrated.
Without knowing the eventual benefits of such a device one might give it a thought.

Henry Farley · Post by **Henry Farley** » 13 Aug 2007, 14:36

Since raising the issue I have not looked since Andy did the first reply.
Must have misunderstood how 'notification' works.
So we have a series of opinions about what is 'a receiver'.
Lester has the right approach but it seems to me that this is a clear case where the Excecutive should take the initiative to clarify the situation, rather than wait for someone else to make a request.
The best way might well be to change the class rules to read "one or more receivers"
As Roy points out there is no perfomance advantage.
Goodness knows why only one was ever allowed.

Lester · Post by **Lester** » 13 Aug 2007, 15:52

As far as I can see, it is clear that the DX6 and especially the DX7 systems have two receivers, as stated on their Web site: "The AR7000 dual receiver [is] comprised of a compact main receiver that is linked to an even smaller satellite receiver [...]".

And, it is clear that the class rules state "D.2.4 REMOTE CONTROL EQUIPMENT (a) The following is permitted: (1) One receiver".

What is under discussion is what an IOMICA Technical Committee might recommend to the IOMICA Exec and the World Council.

One approach might be to argue that the intention of the class rules is surely not to prohibit an effective and popular system of radio control, and that nothing needs to be done. This approach has certain attractions, mainly in that it avoids any risk which comes from trying to do something about it and the possible upset to owners who already have Spektrum systems. The down side, of course, are the other risks -- that there may be inconsistent application of the class rules by different measurers or event organisers who understand the intention of the rules differently, or that a perception may grow that the class rules don't really matter. If I understand Roy correctly, this would be the approach he would wish to take if he were elected as VC Technical, probably with the added provision that he wouldn't even want to put the matter on the agenda of the Exec or the World Council.

Another approach might be to argue that, whatever the intention of the rule might be, it nevertheless clearly prohibits the AR7000 dual receiver, and so the rule needs to be changed. This approach has attractions and risks which are pretty much the converse. There is always the risk that, in "fixing" the rule, things are inadvertently made worse. There is also the risk that some owners might already have installed the AR7000 and would not take kindly to discovering that there is some debate about its legality. The attraction of this approach is that action to change the rule shows that the class rules are being taken seriously and anomalies are dealt with promptly. This would be the approach I would wish to take if elected as VC Technical, in making a full recommendation to the Exec and the World Council.

It might be worth seeing if we could have a principled debate about these issues that the Spektrum receivers bring up, rather than childish name calling and mud slinging.

RoyL · Post by **RoyL** » 13 Aug 2007, 18:14

I will gladly address this topic.

First, and most important, the question at issue is not what Lester Gilbert or anyone else "thinks" is legal or illegal under the IOM Class Rules.

Under our class governance system, it is a National Class Association's request for a formal technical interpetation that triggers a review by the technical committee.

It seems clear to me, that if not a single member NCA thinks an issue requires clarification then unilateral action of the Technical Committee is neither required nor proper.

Lester Gilbert suggests that if issues are left alone "there may be inconsistent application of the class rules by different measurers or event organizers who understand the intention of the rules differently, or that a perception may grow that the class rules don't matter." However the record clearly speaks for itself.

For the past two plus years, there has been no "proactive" rule making as Lester suggests is necessary. What has been the result? Stability, harmony and growth. Has there been inconsistent application of rules by anyone anywhere? Absolutely not. Has there been any indication from any source that the "class rules don't matter"? None whatsoever.

Contrast the above with Lester Gilbert's historical track record. Under his leadership, proactive technical review was encouraged. The result? Among other things, the banning of Black Magic Sails; the banning of Texalium hulls; a proposed ban on colored fiberglass tubes (and hence Brad Gibson's Disco); and my personal favorite, permitting of jibs to be pivoted from the bottom of the hull because it was impossible to formally define the term "deck". Was there instability in the class? You bet. Was there a widespread belief that the rules were being manipulated in favor of certain individuals? Absolutely. Was there a growing sense in the class that the rules didn't matter? Yes, yes, yes.

I have spent over twenty years as an attorney drafting everything from multi-billion dollar merger agreements to labor union constitutions. I have worked with CEOs, atheletes, movie stars and ordinary working people. I have testified before the United States Congress and advised national state and local legislatures. One thing is certain--there is no such thing as totally clear and unambiguous language. Spend enough time focussing on something, put enough effort into looking for problems, and you will surely find them.

Look at the "question" of the Spektrum receiver. You can choose to focus on the fact that the product is described in the singular as a "receiver". You can also focus on language where the product is called a "dual receiver" (a seeming contradiction). You can look at other language that talks about a "main" receiver and a "satellite" receiver. You could focus on the circuits being employed and find that the "satellite" receiver can not function on its own. If you wanted to really confuse yourself, you could note that the Spektrum and virtually every other receiver also functions as a voltage regulator and wonder if such dual functionality is also problematic. Look hard enough and you will only find more questions, not a clear answer.

Fact is, however, the class has effectively already decided this issue. There is no performance advantage to the Spektrum system and the device functions as a single receiver. The Spektrum equipment has been widely adopted around the world without questions or protest. Most importantly, there has not been a single request from an NCA to rule on the legality of the Spektrum receiver. In such circumstances I believe it would be wrong for VC Technical to insert itself into the process and the Spektrum should be considered class legal and "one" receiver.

There is a clear difference between Lester Gibert and me. I believe in democracy and put my faith in the class members and the NCA's to surface important issues. I believe "if it ain't broke don't fix it." I have seen the results of "proactive" technical governance of the IOM Class in the past and I believe not only that it is the wrong direction, it is a demonstrated failure. I stand on the record of the past two plus years and the growth and stability in the class. I would be honored to continue to serve.

Marko Majic · Post by **Marko Majic** » 13 Aug 2007, 18:24

A most interesting topic (but who could expect any less from Henry F.)

I disagree (of course

) with a view that Spektrum receiver is comprised of multiple receivers and hence illegal in the IOM class (perhaps because I own one

).

In determining what something is (and, therefore, whether it is suitable or "class legal") I don't think we should use company's marketing materials or promotional literature or anything of the sort (otherwise I would happily bribe a c/f tubing manuafacturer into putting a sticker with something like "The most advanced grade of 7075 alloy on the market" onto their carbon fibre tube and use it as a mast for my IOM

).

In the same vain, statement like:

The AR7000 dual receiver [is] comprised of a compact main receiver that is linked to an even smaller satellite receiver [...]

does not necessarily mean that this is indeed the case - simply that the manufacturer is trying to find ways of extolling the virtues of their particular system and finding ways of differentiating themselves from others (by inadvertent(?) use of misleading or inaccurate statements).

Of the many definitions of the term "receiver" the ones that make the most sense to me in our application (and, at the same time have nothing to do with American football or paying taxes) are ones from the electronics and radio industry which state:

Electronics. A device, such as a part of a radio, television set, or telephone, that receives incoming radio signals and converts them to perceptible forms, such as sound or light.

Another definition (from the radio industry) states:

Receiver (radio), an electronic device that converts a radio signal from a transmitter into useful information

They both agree, therefore, that in order for a device to be a receiver it not only has to be able to listen but also to convert.

Without the converting function the device, I imagine, is merely a listener and not a receiver - and is internal to the compound device - which is a receiver.

The fact that Spektrum units only have one set of terminals from which to tap the information means (IMHO) that it is a single receiver. In other words, it can only convert signals from a single transmitter and it doesn't, AFAICS, make one bit of a difference how many auxiliary listener (for a lack of a better term) units it employs in order to insure/improve fidelity/reliability of its reception and whether those are internal or external to the system (DX-6 vs DX-7) just as it doesn't really matter what other types of tricks it employs towards the same goal (e.g. PCM modulation, r/f filters or whatever else is inside the box or linked to it electrically).

Cheers,

Marko

Andy Stevenson · Post by **Andy Stevenson** » 13 Aug 2007, 20:04

Hi Roy

it is a National Class Association's request for a formal technical interpetation that triggers a review by the technical committee

The Technical Sub Committee is responsible for the initial action in such a case certainly, but itâ€™ not their only role.

I believe it is the responsibility of the TSC to react to any changes that may affect the Class Rules. The latest changes to the ERS are a good example. No NCA requested an interpretation in that case.

It seems clear to me, that if not a single member NCA thinks an issue requires clarification then unilateral action of the Technical Committee is neither required nor proper

Conversely, I feel it would be irresponsible of the TSC not to investigate the implications of relevant, accurate, information brought before it or reasonable questions put before it, regardless of the source. Unilateral action may not be appropriate, but a conversation within the TSC would be.

Fact is, however, the class has effectively already decided this issue.

Effectively yes. But that doesnâ€™t address the question â€œIs the Spektrum receiver class legal?â€

RoyL · Post by **RoyL** » 13 Aug 2007, 23:35

Andy, its hard for me to follow what you are suggesting.

On the one hand you seem to accept the concept that the Executive and the Technical Committee should not take unilateral action.

But then you suggest that the Technical Committee should "investigate the implications" of information or questions "regardless of the source."

To what end? To issue a ruling to the class? That would be taking unilateral action. To advise the Exec? Well, unless and until a formal request for a technical interpreation is raised by an NCA you can't even properly frame the discussion. To generate discussion among the class members? Perhaps in an academic setting long discussions of what might or might not possibly happen are fruitful. In the real world, they bear little practical value and often lead to confusion.

Similarly, you appear to be suggesting that when a single class member raises a question, the Technical Committee needs to take "action". Again, this seems to be calling for the Technical Committee to take it upon itself to act without receiving a request for a rule interpretation from an NCA or the World Council.

In fact, the system that we have works fairly well. We have the IOMICA Forum as a first stage in any process. The Forum allows any class member with an issue or concern to express their opinions. Voices can be heard from all sides. If the issue is important enough, there will be a flurry of activity on the forum and sooner or later the question will be put to the IOMICA Exec or Technical Committe by a National Class Authoirty. If on the other hand, the issue is not of general concern to the class the discussion dies down and the issue remains dormant.

Such has been the case of the Spektrum Receiver. A discussion took place largely between Lester, Andy and one other class member. The discussion then lost momentum. Not a single NCA took up the question and asked for a rule interpretation. No event measurer declared the receiver illegal. No class member filed a protest asking that a boat be deemed illegal for using Spektrum equipment. The Technical Committee was not called upon to act and it did not act unilaterally. DeFacto, as I said previously, the Class has determined that the Spektrum equipment is legal. In my mind, the process has worked perfectly.

Lester · Post by **Lester** » 14 Aug 2007, 00:22

It seems Roy is unaware of the official position of the IOMICA Technical Committee.

From http://www.iomclass.org/technical/ wrote:Where the IOMICA TSC becomes aware of a discussion about the class rules that, in its view, should be the subject of an interpretation, the TSC may make an official request on behalf of the class.

It is of course entirely legitimate for the Technical Committee to make recommendation to the Exec or World Council on matters which have come it its attention. Not only is it legitimate, in my view it is its responsibility. This hardly constitutes "unilateral action", whatever that is.

But this nicely reflects the difference between the two approaches I identified earlier in this thread.

Roy thinks nothing should be done about the Spektrum issue. In order not to take any action, he must effectively issue a declaration that the system is entirely legal, ignoring any argument to the contrary. Hang on, didn't Roy just claim that this was the sort of undemocratic, high-handed, stamping on the class members surfacing of an issue type action Lester was allegedly infamous for?

Me, I don't *know* whether the Spektrum is legal. I suspect it isn't. On the face of it (Marko's arguments are ingenious, but do not convince me!) there is an entirely legitimate basis for asking for an Interpretation. C'mon, "everybody knows" the Spektrum has two receivers, while the class rules permit exactly one. There is an issue here! Admit it!

To handle the possibility that an Interpretation (which would come from the Joint RSD-IOMICA Committee, NOT from the IOMICA Technical Committee or anywhere else!) declares Spektrum to be illegal in the IOM Class, I would have in my back pocket a request for an emergency rule change (which would go at the same time to the same Joint RSD-IOMICA Committee) to address the issue. Problem solved, job done that the Technical Committee is expected to do, surely?

Andy Stevenson · Post by **Andy Stevenson** » 14 Aug 2007, 01:14

Hi Roy

On the one hand you seem to accept the concept that the Executive and the Technical Committee should not take unilateral action.

Quite right, given that my understanding of â€œunilateral actionâ€

RoyL · Post by **RoyL** » 14 Aug 2007, 04:03

Let me get this straight. If elected to the job of VC Technical Lester Gilbert will take the position that the "two box" Spektrum receiver is illegal for use in IOMs?

I can't wait to see how that works out.

Andy Stevenson · Post by **Andy Stevenson** » 14 Aug 2007, 04:37

Hi Roy

Roy wrote:Let me get this straight. If elected to the job of VC Technical Lester Gilbert will take the position that the "two box" Spektrum receiver is illegal for use in IOMs?

It would appear you havenâ€™t got this straight Iâ€™m afraid. What Lester actually wrote was:

Lester wrote:Me, I don't *know* whether the Spektrum is legal. I suspect it isn't.

Roy wrote:I can't wait to see how that works out.

Lesterâ€™s post continues to outline how he would approach seeking an interpretation from the joint RSD / IOMICA Technical Committee, and have an emergency class rule change request ready to submit to that same committee if Spektrum receivers are interpreted illegal.

So you donâ€™t need to wait to see how it works out. The outcome is either an interpretation that the Spektrum receiver is legal and no further action is taken, or an interpretation that it isnâ€™t legal and an emergency rule change to make it legal.

Following this course of action the question is answered and Spektrum users can continue safe in the knowledge that their radio gear is legal, IOMICA takes the Class Rules seriously and VC Technical responds to reasonable questions.

I understand that this is in opposition to your suggestion of doing nothing. And I must point out that this is only my personal opinion, not necessarily the opinion of an Executive Committee that I might chair. However it does reinforce my opinion that Lester is the better candidate for VC Technical.

Barry Fox CAN262 · Post by **Barry Fox CAN262** » 14 Aug 2007, 05:54

Well, this has disintegrated into more BS that has little to do with common sense or that actual topic. I'd suggest we start a new Index heading called something like "Bashing" and have this type of "discussion" take place there. There is little discussion going on here just a lot of posturing and little meaningful contribution.

I have been involved in International sporting class rules before, just not sail boats.

The road this is all on right now with this incessant bickering will serve very well to destroy the enthusiasm many have for these terrific boats.

In my many years of corporate politics my experience is that very few people a skilled or proficient at politics. Certainly I have yet to see anyone show that any degree of micro-management works. I have seen some very smart managers try to be micro-managers and the only thing that resulted was an ineffecient operation.

The idea that the configuration of a receiver somehow makes it legal or not is completely preposterous. The exact function is that a signal is sent from the Tx and the device known as a receiver (regardless of how many antennae it has) receives one signal and converts that into an instruction for one of the two control devices we are allowed to have. You cannot, as previously stated when this thread last died, purchase the components of a DX7 receiver seperately. You don't order receivers from Spektrum (or anyone else), you order a receiver - one only. What you get, in the case of a DX7 system, is two pieces of plastic joined by a piece of wire that function only as a single unit.

I am so glad to see that everything else within the class is so clear and so well understood that we have to spend this much energy on something that has absolutely no influence on boat performance or cost.

There are certainly bigger issues around how the class is managed markedly differently in different countries that would be much more important in my opinion but no one else thinks that is a problem so . . .

Anyway, the topic is two antenna receivers. You guys work out the personal stuff somewhere else and deal with the question.

Keep going at it like this and all that is going to happen is a splintered class that is governed regionally and quite differently. You will end up being the ruling patrons of an International class that few care about.

This discussion is turning out to be as goofy as the topping lift elastic, multi colored sails, etc.

RoyL · Post by **RoyL** » 14 Aug 2007, 06:07

Barry: I couldn't agree more with your post. This kind of bickering was exactly how things were before Greg Willis became IOMICA Chairman.

Until now no one seriously thought that the Spektrum equipment was illegal for use in the IOM.

If IOMICA makes the unilateral decision to ask the RSD/IOMICA Technical Committe to issue a ruling on this question based on prior history it is highly likely that they will outlaw Spektrum equipment. The fact that Lester Gilbert has already expressed the opinion that he believes Spektrum equipment is illegal, I'm sure will have an effect on the process.

Of course, as suggested, IOMICA can then write new emergency rules to fix the problem it created in the first place. If lucky, the RSD will agree to the new rules, if not, well, I dont' know what the class will do. And if there is a problem or a loophole in the new rules? We can pass more rule changes to fix the new rules.

Barry, all I can say is I'm sorry this is happening. I wish there was some way to make it all go away.

ralph kelley · Post by **ralph kelley** » 14 Aug 2007, 16:06

Am I the only one getting weary of all this bickering? Am I the only one thinking of getting into a different class so we don't have to have be involved in all this B...S.., either directly or indirectly?

Roy is right about the history, and I would add, the problem of attaching an elastic to the end of the boom to his list. I think there is a clear relationship between these "problems", i.e., rule issues that had no impact on performance and the folks involved.

I can not think of a better way to kill the class than to continue this way of looking at this hobby.

Respectfully

Ralph Kelley

Lester · Post by **Lester** » 14 Aug 2007, 16:14

RoyL wrote:If elected to the job of VC Technical Lester Gilbert will take the position that the "two box" Spektrum receiver is illegal for use in IOMs?

Hi Roy

Not at all. As I made quite clear in my post, my position is that there is a prima facie case to ask for an Interpretation.

I can't wait to see how that works out.

I explained that as well. Simultaneously with the request, in case it goes the way that we both know it is likely to go, is a request for an emergency rule change, because absolutely no one I know thinks that the Spektrum system is against the intent of the class rules or against the interests of the class. I see no danger at all that the Joint RSD-IOMICA Committee would refuse such a rule change.

We have a situation where an IOM owner posts in, saying "My X seems to have two Z's, but the Class Rules permit only one Z. Is there an issue?"

Your approach seems to insist upon your own personal interpretation that the X "really" only has one Z, that the Class Rules do not really mean "one receiver", they really mean "anything functioning as a single output receiving system", and that only two people in the class seem to think there is an issue anyway. Hang on, isn't this undemocratic, high-handed, stamping on the class members surfacing of an issue, sweeping the issue under the carpet?

We both agree that a set of rules, no matter how carefully drafted, will always have two problems: (1) inevitable errors and inconsistencies because rule writers are only human; and (2) inability to accommodate the unexpected because, ah, the rule writers do not have functioning crystal balls.

The Spektrum situation is an outstanding example of item (2). At the time the rules were written, specifying 'one receiver' seemed a perfectly safe and sensible rule to write. A few years later, it turns out that this is now an unexpectedly poor rule.

The discussion we are having, and we absolutely should be having, is what to do when items (1) and (2) are revealed in the IOM Class Rules.

For me, it doesn't matter who reveals the issue or how it comes to be revealed. Once revealed, it is entirely legitimate that it be discussed and opinions heard. Once revealed, the issue needs to be dealt with properly, not by giving ridicule to anyone who thinks differently. It is completely pointless to rubbish the messenger because you don't like the message.

Your approach is to do nothing, while rubbishing anyone who thinks differently. My approach is to do something, while having a principled discussion on the issues.

Lester · Post by **Lester** » 14 Aug 2007, 16:24

ralph kelley wrote:I would add, the problem of attaching an elastic to the end of the boom to his list. I think there is a clear relationship between these "problems", i.e., rule issues that had no impact on performance and the folks involved

Hi Ralph

The problem of attaching an elastic to the end of the boom was due to the fact that the class rules did not mention the boom as a permitted point of attachment. A curious omission, with hindsight, but true.

So what, exactly, did the omission of the word "boom" in Class Rule C.7.7(a)(c) have to do with the folks involved, please? Not shooting the messenger again, are you?

RoyL · Post by **RoyL** » 14 Aug 2007, 16:25

Lester: Please listen to what others are saying. I won't engage in this anymore, the "discussion" you want to have is hurting the IOM Class.

We disagree, that's it. For the good of the class, leave it be.

Lester · Post by **Lester** » 14 Aug 2007, 16:30

Roy: Please listen to what others are saying. The "discussion" you have given us is hurting the IOM Class.

We disagree. For the good of the class, let's be clear on who thinks what so the owners and NCAs can vote in an informed way.

Barry Fox CAN262 · Post by **Barry Fox CAN262** » 14 Aug 2007, 18:45

I was going to address this to an individual but then that gets personal.

But this discussion is stupid!!! There is no technical discussion going on here. All that is happening is that certain individuals are trying to be right at some lofty degree of assumed superior intellect. All that is coming across is a complete ignorance of understanding what the majority wants.

Common sense!!! It just isn't coming across.

I hope my NCA is reading these posts and adjusting their opinion accordingly. I haven't been polled to see if I want to nominate any of these people so far and you can guess what my input will be.

This is as ridiculous a "discussion" as the ones about the elastic and multi-colored sails.

It would be a shame to drive people away from this class because of a ridiculous academic position on something as simple as what constitutes a receiver. Keep making the references to Spektrum, I love it. Please write "the rule" to cover Spektrum radios as that will leave mine alone.

Talk down to the masses much more and the ensuing result will be your own doing.

Lester · Post by **Lester** » 14 Aug 2007, 23:30

Hi Barry

In another forum, you seem to say, "[Lester's approach is] let's make what is now a common thing to use illegal".

I'm scratching my head trying to understand what you might actually be saying.

We are both agreed that the Spectrum system is a good one and in common use and poses no harm or threat to the IOM. Other DSS 2.4 GHz systems likewise.

I think we are both agreed that the Spektrum AR7000 is a "dual receiver" comprising "a master receiver" and "a slave receiver" (I quote their own words). Great technological solution, by the way, to the problem of ensuring glitch-free reception.

We are also agreed that the IOM Class Rules, bless their cotton socks for being the product of fallible human beings, somehow say "D.2.4 REMOTE CONTROL EQUIPMENT (a) The following is permitted: (1) One receiver".

Finally, I think we are both agreed that there seems to be an unfortunate issue here. On the face of it, the Class Rule seems to be saying that the AR7000 is not a legal item of equipment in an IOM.

My approach is to seek an Interpretation. That is, to go and ask some folks whose job it is to decide such matters, what they think.

In what way, please, is this me deciding to make the AR7000 illegal? In what way does me asking the question, "Excuse me folks, tell me, is this legal?" make it illegal? Can you see why I'm scratching my head?

Hiljoball · Post by **Hiljoball** » 15 Aug 2007, 01:08

This discussion highlights the difference in the approach to running the class. The differences exposed here, are far more important than the question raised.

The Spectrum is quite a different issue to the Texalium and sail manufacturing items that have been quoted in this sorry thread. When a manufacturer sets up to manufacturer an IOM specific product, it behoves them to make sure, in advance that their commercial product complies with class rules.

When an IOM skipper goes out to buy a radio set, and gets a transmitter and a receiver and a couple of servos, he/she has met the spirit of the class rules. We cannot expect the skipper to comprehend the nuances of electronic design. He/she bought one receiver! The term â€˜receiverâ€™ refers to a system that plugs into batteries, receives instruction from a transmitter and controls two servos.

To read any more into it than that is just plain dumb! These radio sets have been around for a couple of years. They have been used in national and international events. There have been no protests lodged. There has been no request for a ruling. The class has accepted a commonsense understanding and has benefited from some new technology.

RoyL · Post by **RoyL** » 15 Aug 2007, 01:16

John: I agree 100% percent. And that's why as current VC Technical I have not initiated any actions regarding the Spectrum.