Which 2.4 system ?

[BILL OXIDEAN]

Put the Airtronics under your pillow and you'll fall asleep faster, have sweeter dreams, wake up feeling recharged and ready to take the world by the @$$.

Just playing Bill!!

I'm all out of popcorn, time to drive on.

Doug

Doug, last time I did that the transmitter ended up in the abortion clinic lol
I guess she didn't realize just how I felt about her

[BILL OXIDEAN]

Bill - Can you please explain the differences between the 2.4 GHz spread spectrum implementation schemes used by Futaba, Spektrum/JR, and Airtronics and why you feel that the Airtronics methodology is the better solution?

Also, you have made statements about the system latency of the new Airtronics radios. Can you provide any data that supports your statements? I am also interested in knowing your opinion on latency versus resolution and how that effects the overall response of the radio.

Bill I'm not familiar with the affects of resolution, but I will ask and get back to you..
I know that you're VERY adept when it comes to radios, and after racing for reputable mfgr for years as you have, I'll be savvy like you as well with em

Here' s what they gave me: 2. Super Response Servo and Receiver for the M11X
Sanwa has developed a new receiver for the M11X (in the same case as the
current M11X receiver) with a latency minimum rating of 2.5ms. That makes
it about twice as fast as the next fasted receiver in the industry

[BILL OXIDEAN]

I just had to stop by and have a laugh at this, you cant beat the irony of advertising a product using terminology you don't understand and getting it wrong.

.

Good morning Paul, I've heard the term latency used many times when referring to radios, and the context its been used in has led me to believe it affects the response speed of the radio as stated here:

2. Super Response Servo and Receiver for the M11X
Sanwa has developed a new receiver for the M11X (in the same case as the
current M11X receiver) with a latency minimum rating of 2.5ms. That makes
it about twice as fast as the next fasted receiver in the industry

Hey, I may be wrong, and stand corrected if I am, but that statement from them leads me to believe latency is associated with response time.

In conditioning, the period of apparent inactivity between the time the stimulus is presented and the moment a response occurs.
Source(s):
dictionary.com

Latency is the amount of time that it takes for information from your computer to travel to the source. Latency should not be confused with bandwidth, as bandwidth measures how much data you can move in a given period of time, but not necessarily how fast it moves.
For example, if I am connected to a computer in the next country, latency measures how long it takes for each letter that I type to travel to the other computer. Latency is important when someone is directly interacting with another computer, as the amount of "lag" between the two computers can make some tasks very difficult (such as editing a file).

I'm sorry Paul, but every source I've checked supports my statement of latency being response time, and as stated Airtronics has a latency of 2.5 ms which is twice as fast as the next leading mfgr.

[Flying Scotsman]

Bill O:

Douggie

[BILL OXIDEAN]

Bill - Can you please explain the differences between the 2.4 GHz spread spectrum implementation schemes used by Futaba, Spektrum/JR, and Airtronics and why you feel that the Airtronics methodology is the better solution?

Also, you have made statements about the system latency of the new Airtronics radios. Can you provide any data that supports your statements? I am also interested in knowing your opinion on latency versus resolution and how that effects the overall response of the radio.

Bill, I don't know the differences, I just know that our radios are amazing lol Not sure of the specs on what frequency ours transmits its signal, but I would assume that its a higher one than most in order to optimize such latency.

At the end of the day, I go by how the radio physically responds and there's no doubt that the M11X out responds anything I've tried by FAR I'm on no quest to prove the radios are great, the performance, wins, reputation, and many testimonials speak for themself.

[NativePaul]

Bill, your right about what latency is, but wrong about how it applies, for our purposes more latency is bad an less latency is good.

What you said was basically that Airtronics has twice as much lag between the user and the model than any other radio including Futaba and Spectrum, and then you went on to enthuse about the benefits of a system with less lag, which if what you said previously was correct would be any radio system apart from Airtronics.

[BILL OXIDEAN]

Bill, your right about what latency is, but wrong about how it applies, for our purposes more latency is bad an less latency is good.

What you said was basically that Airtronics has twice as much lag between the user and the model than any other radio including Futaba and Spectrum, and then you went on to enthuse about the benefits of a system with less lag, which if what you said previously was correct would be any radio system apart from Airtronics.

Ok now I see what you mean, to clear things up, I meant half the latency not twice since the lower the number which in this case is 2.5ms

Our previous system had a latency of 5ms

So in other words less is more which Airtronics has the lowest latency

[Bill-SOCAL]

It amuses me after nearly 45 years in RC how latency has become the new religion in many parts of the RC work.

According to one advertisement I have seen done by Sanwa they claim and average latency of 4 milliseconds versus 7.7 average for the Futaba 4PK. All well and good. 4 is certainly less than 7.7. 3.7 milliseconds less.

Latency Chart for M11X radio:

http://www.hobbypeople.net/gallery/751568.asp

But the real question is does that really mean anything? Probably not is the answer. First, human reaction time averages around 215 ms. Here's a fun link where you can measure your:

http://www.humanbenchmark.com/tests/reactiontime/index.php

So in the real world the worst part of the whole deal is how fast we can observe a change and initiate a response. The radio latency gets added to this of course.

So for the average person we are talking about a range of between 219 and 222.7 milliseconds. That 3.7 millisecond difference between radios amounts to about 1.7% of the human average reaction time (human latency). Honest to God Bill, if you are good enough to feel that difference more power to you.

My average reaction time on the above test was 236 ms. So for me it is a waste. Here is further evidence. My 8 channel receiver in my pattern plane can have the frame rate set for either 14 ms or 7 ms, effectively halving the latency. Guess what? I cannot tell the difference in flight with a high precision pattern plane. And reports for 3 members of the US F3A Team were the same. They could not feel any difference.

So if you can feel 3.7 ms when some of the best pilots in the world could not feel a 7ms difference then I tip my hat to you.

For me what is far more important are the servos you use. Whatever the vehicle I always buy the strongest and best centering servos I can. With my emphasis on the centering ability. I want to know that the servo will return to its starting point as nearly as possible 100% of the time.

Another aspect you ignore is resolution. I have not seen any specs from Airtronics of their system resolution. Futaba is 2048, meaning there are 2,048 discrete steps from end point to end point. This is critical to how the radio "feels". For instance, in airplanes, the difference between 1024 and 2048 is truly remarkable. While as I said the difference in latency of 7 ms was unnoticeable to even world class pilots.

Finally you did not address my other question about the implementation mode between the various radios. Futaba and Airtronics both use a Frequency hopping spread spectrum method. (FHSS). Spektrum/JR uses a Direct Sequencing Spread Spectrum method (DSSS).

Airtronics and Futaba constantly sweep the entire allocated spectrum of 2.4 GHz that we work on and never stay on a single "channel" for more than 50 ms or so. Spektrum picks two "channel" and locks on those at start up. If problems are detected with one the radio hops to the other. If it is swamped the radio will try to hop back. If both are swamped then you are dead meat. A "channel" in this use is a chunk of spectrum that is used to send the information to the receiver. It is not a channel like we used to think of with non 2.4 radios.

Another issue is power. A recent test done by Spektrum showed that their systems will lose link when system power drops to 3 volts. They have a new deal that they call "instant on" or something like that where the lag of regaining the link when voltage recovers is near zero. In that same test the Futaba never lost link even down to a couple of volts. Almost all digital servos use a 3 volt single voltage so none of those work below 3 volts. But I like the idea of my system staying linked regardless of the system voltage. I have no idea how Airtronics handles low system voltage.

Bottom line is that all 3 major vendors have robust 2.4 systems that all appear to work fine under most conditions. Each person needs to realistically evaluate the strengths and weaknesses of each and decide for themselves which will be the best for them.

A final thought for you Bill. Your opening statement that Airtronics is the world's leading radio manufacturer is simply pure fantasy. It does not mean they do not make a decent product, but really, be serious, the "world's leading manufacturer"??

[Steven Vaccaro]

My average reaction time on the above test was 236 ms.

Dam, I had to work to break 300. Now I know why my kids kick my butt when i play them on xbox.

[longballlumber]

Dam, I had to work to break 300. Now I know why my kids kick my butt when i play them on xbox.

That one made me laugh Steven!!!

[befu]

response time

My average was around 240, my best was still above 200, couldn't get better than 200. This has taught me one thing. My ping rate on some online first person shooter games is around 50 to 80ms. (Yeah, I know, geek. Back off!) I always figured I was getting my butt kicked due to computer and internet lag. With the computer running at 50 to 80 ms and my average response time when I am concentrating on one red box is 240ms, I am losing the game because I suck, not the computer speed! Now I have nothing to blame it on but me....

this ms response time thing seems odd to me too. At work we use PLC's. I am amazed at the scan time and we constantly have to be careful how it is programmed because it can think so fast you can miss a signal. So when you talk about a servo mechanically responding a few ms faster, I do not see the use of it for boats. Space craft reentry, sure. But not for me.

They make fine products, look at all the details and your application like others have posted, then decide.

Brian

[Bill-SOCAL]

Despite being above average on the times I think I owe my low (for my advanced age) time to having to be quick like a bunny on the LA Freeway system just to stay alive.

And FWIW, I actually slow my steering servos down to smooth out the driving. Cars and airplanes need lightning quick servo response. Boats I think actually are hurt by it.

[Jeepers]

reaction time

Hmm not bad 219.4 ms average, I wonder how I would do If I had more than three hours sleep. (sick 2 year old boy)

[CornelP]

213.2... not bad for 6.30 in the morning... Thanks for that, Bill.

[BILL OXIDEAN]

Bill, after all of that explanation, the fact still stands that the latency of a radio has NOTHING to do with human reaction lol.. if my latency is 300 and the radio's is 300 that's a compnied latency of 600. If mine is 300 and the radio's is 2.5 I will have a combined latency of 302.5.

A sluggish driver combined with a sluggish radio= sluggish performance
A driver with slow response will benefit from a faster radio hands down. I can't believe no one posting can understand that but take time to TRY and prove what I say is invalid, but I prove different every time.

Everything I've stated is a true valid fact.
hey, if none of my competitors decide to get the advantage of the fastest (by far) system on the market, then that's more power to me, but the fact is that no matter what I say or how much you try to contradict it Airtronics radios are the world's top selling radios.