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Old 04-25-2005, 06:42 AM   #31
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I guess it will force Spectrum to up the number of channels available. Or release some binding systems from 81-160 or 200 for in the future.
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Old 04-25-2005, 11:50 AM   #32
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Good points....I can see where you are coming from if at a LARGE event where you may have the possibility of 80+ spread spectrum radios in the future.

Worst case scenerio if 80 people were in the pits all testing/tuning at the same time (still highly unlikely) this may prevent someone from actually being able to race in their heat/main.

I'm not a "tech" guy, but why is there a limit to 80 frequencies for spread spectrum radios when you have unlimited frequencies for AMBrc transponders??

Also, something else I was thinking about. Someone mentioned that "explaining" the 2.4Ghs theory to non 2.4Ghs users would help with any confusion in the pits....Very true, but what if 2.4Ghs users had a special "2.4Ghs" clip they can display on their antennas so other racers will be able to visually tell that another racer is on 2.4Ghs???

Just throwing "stuff" on the wall....

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Old 04-25-2005, 11:54 AM   #33
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Quote:
Originally posted by Ray Murray


Also, something else I was thinking about. Someone mentioned that "explaining" the 2.4Ghs theory to non 2.4Ghs users would help with any confusion in the pits....Very true, but what if 2.4Ghs users had a special "2.4Ghs" clip they can display on their antennas so other racers will be able to visually tell that another racer is on 2.4Ghs???

Just throwing "stuff" on the wall....

you mean that module with the little antenna sticking out of it isn't a big enough give away that your running DSM?
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Old 04-25-2005, 12:20 PM   #34
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Quote:
Originally posted by Ray Murray


I'm not a "tech" guy, but why is there a limit to 80 frequencies for spread spectrum radios when you have unlimited frequencies for AMBrc transponders??

Also, something else I was thinking about. Someone mentioned that "explaining" the 2.4Ghs theory to non 2.4Ghs users would help with any confusion in the pits....Very true, but what if 2.4Ghs users had a special "2.4Ghs" clip they can display on their antennas so other racers will be able to visually tell that another racer is on 2.4Ghs???

Just throwing "stuff" on the wall....

Ray - The Spektrum DSM system is based on frequency, not numerical value like the AMB personal transponders (9 digits too, virtually unlimited yes, as it relates to the RC industry) but the RF is not. As the Spectrum stands right now, it has usuable space as dictated by the FCC in the 2.4ghz band so it has some limitations to what frequencies it can use.

Maybe this can be of use to answer questions: http://www.spektrumrc.com/DSM/Better/Default.html

And having a DSM clip or flag on your transmitter antenna? Well, I don't think anyone would see it since the antenna is only 3" long as Matt Howard pointed out.
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Old 04-25-2005, 12:25 PM   #35
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Quote:
Originally posted by Matt Howard
you mean that module with the little antenna sticking out of it isn't a big enough give away that your running DSM?
LOL, I mean, there will still be a lot of people that have no idea what a spread spectrum radio is or what it looks like. From a few feet away, it might not be noticable to people who don't know the difference.

I guess I'm referring to the club racing scene....

BTW, Mike (I wannabe Matt Howard) Ivy said hi yesterday....LOL

Last edited by Ray Murray; 04-25-2005 at 12:42 PM.
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Old 04-25-2005, 12:28 PM   #36
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Quote:
Originally posted by John Fontaine
Ray - The Spektrum DSM system is based on frequency, not numerical value like the AMB personal transponders (9 digits too, virtually unlimited yes, as it relates to the RC industry) but the RF is not. As the Spectrum stands right now, it has usuable space as dictated by the FCC in the 2.4ghz band so it has some limitations to what frequencies it can use.

Maybe this can be of use to answer questions: http://www.spektrumrc.com/DSM/Better/Default.html

And having a DSM clip or flag on your transmitter antenna? Well, I don't think anyone would see it since the antenna is only 3" long as Matt Howard pointed out.
Thanks John! All this high falootin, new fangled technology is fascinating to me...LOLOL
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Old 04-25-2005, 12:33 PM   #37
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No prob ray. You race directors should love this since it takes some of the stress away from you guys
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Old 04-25-2005, 04:12 PM   #38
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John is right, the bottom line for race directors is that radio impound should not be neccessary with 2.4Ghz systems, and in fact, the elimination of frequency conflicts and coordination is the major advantage of 2.4Ghz systems.
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Old 04-25-2005, 05:04 PM   #39
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Originally posted by nimble
John is right, the bottom line for race directors is that radio impound should not be neccessary with 2.4Ghz systems, and in fact, the elimination of frequency conflicts and coordination is the major advantage of 2.4Ghz systems.
Thats until you have 80 drivers with their radios on testing and tweaking and 10 guys on the rostrum cant find a free channel to start the race...

Yup its very unlikely, but what about that wireless network broadcasting the live results to peoples PDA's using multi channel wide band 2.4ghz?

Its not a solution to an impound, it just reduces the need until it gets widely adopted....

Nimble, hows your system coming along? Is it launched now?

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Old 04-25-2005, 05:55 PM   #40
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Galifrey, our DART system has been announced, see our updated website.
More details will be forthcoming on the website. FCC testing is complete, just waiting for paperwork to be officially filed.

The DART system is actually very different than the Spektrum, we use an RF link that is 4 times faster, and use FHSS,
a system invented by the military to prevent jamming of battlefield communications from interference, which is constantly changing channels 100's of times a second. We can have potentially up to 250 people running at once. We could support 1000 people at once if needed with small changes to the system.
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Old 04-25-2005, 06:03 PM   #41
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Quote:
Originally posted by nimble
Galifrey, our DART system has been announced, see our updated website.
More details will be forthcoming on the website. FCC testing is complete, just waiting for paperwork to be officially filed.

The DART system is actually very different than the Spektrum, we use an RF link that is 4 times faster, and use FHSS,
a system invented by the military to prevent jamming of battlefield communications from interference, which is constantly changing channels 100's of times a second. We can have potentially up to 250 people running at once. We could support 1000 people at once if needed with small changes to the system.
I'm guessing you meant to call the receiver the "raceiver." As a combination of racing / receiver right? If not you have a typo on your website.

Also...I always wondered why your company was called Nimble motorsports until I saw that your name is Jack.... Clever.

I wish you the best of luck. It seems your gaining some name recognition within the industry.
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Old 04-25-2005, 06:22 PM   #42
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Quote:
Originally posted by nimble

The DART system is actually very different than the Spektrum, we use an RF link that is 4 times faster, and use FHSS,
a system invented by the military to prevent jamming of battlefield communications from interference, which is constantly changing channels 100's of times a second. We can have potentially up to 250 people running at once. We could support 1000 people at once if needed with small changes to the system.
What does FHSS means ? I think this is the "bomb" weve been waiting for. I guess my Spektrum is headed for auction. Ebay ! Is Dart ROAR approved yet ? What the price for the complete tx/rx system? Can't wait. Thanx

Henry E.
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Old 04-25-2005, 10:08 PM   #43
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Quote:
Originally posted by jeepnyy
What does FHSS means ? I think this is the "bomb" weve been waiting for. I guess my Spektrum is headed for auction. Ebay ! Is Dart ROAR approved yet ? What the price for the complete tx/rx system? Can't wait. Thanx

Henry E.
It means "frequency hopping spread spectrum."

It naturally should be slower than Direct Signal Modulation considering it has to hop from one band to another several tens of times per second.

However Nimble says he got it to work, so I suppose we should wait and see.

*Note

The guys who developed Spektrumô considered FHSS and discarded it once they found it to be a higher latency than modern crystal-based radios. It's in their FAQ.
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Old 04-25-2005, 11:47 PM   #44
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Yes, FHSS is Frequency Hopping Spread Spectrum. Many existing off-the-shelf FHSS radios designed for Wireless LANS or serial modems like SCADA wireless industrial controls, they switch channels very slowly.

Our system was designed specifically for the real-time control demands of R/C racing, we can switch channels in 200ns, that is nanoseconds, 1/1000000 of a second,
we switch channels 100's of times a second! By the time you pull the throttle from neutral to full-on, it has probably changed channels dozens of times.

Expect to see a review of the DART system in one of the R/C magazines soon.

DART is ROAR approved, no worries.

The good news is the pricing will be very competitive, VERY competitive, as we intend to win.
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Old 04-27-2005, 02:40 AM   #45
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Quote:
Originally posted by nimble
Galifrey, our DART system has been announced, see our updated website.
More details will be forthcoming on the website. FCC testing is complete, just waiting for paperwork to be officially filed.

The DART system is actually very different than the Spektrum, we use an RF link that is 4 times faster, and use FHSS,
a system invented by the military to prevent jamming of battlefield communications from interference, which is constantly changing channels 100's of times a second. We can have potentially up to 250 people running at once. We could support 1000 people at once if needed with small changes to the system.


Sounds like you have a great product for the entire Industry on your hands.... the thing is.... if a Race Director wants to run a very fair race... then the only way they could achieve that would be to require everyone to have the DART System (or similar ones that might be made available) or continue to impoud radios to make sure extra work and problems are avoided as well as keep things on a level playing field for those who choose not to adapt to some of the newer radio technologies. I guess only time will tell. At huge races Personal Transponders are a requirement... this type of technology may one day become one too!?
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