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Transmitter latency - does it really matter?

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Transmitter latency - does it really matter?

Old 05-03-2014, 01:49 AM
  #46  
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Serach came up with this thread.

I tried the reaction time tester, best 183ms, most a touch over 200ms when using the mouse. Around 260ms when using the keyboard. Cool test.

When I tried 2.4 when it first came out I found the latency to be a considerable issues and I switched back imediately to 40Mhz.

Is latency still an issue?
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Old 05-03-2014, 02:49 AM
  #47  
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I'll drop in a first hand report FWIW. I was out for about 25 years and jumped back in with a full upgrade. This meant I had a new car and M12 to break in, (or just break to start with), and a vintage car with an old 27 Mhz radio to compare it with.

My old car drove comfortably and predictably for me. I'm not good enough to worry about shaving inches but things went pretty much where I wanted them.

My new set up had a tragic encounter with a board on the shake down cruise and left me with a well hidden cracked front upright leaving me to chase steering problems along with everything else usually found during break in. I therefore got very involved in learning all the trims, adjustments, rates, curves, and setting available on the M12.

Compared to my old radio, it was much easier to change dual rates, (huge difference), response curves, (assigned to one of the many new trims), and directly related to this thread, the Feel setting. Feel allows you to choose the latency to suit your needs, (also easily assigned to a trim dial), over a range of +/- 5, default being +5. For comparison, the mid setting is suppose to give you the same response of the M11X, ( see pg 69 of the manual.)

From what I could tell before and after finding and fixing broke car parts, the Feel function is probably the least responsible for the overall performance of the car. For what ever setting I chose, modifying dual rates, response curves, and balances of brake trims would overwhelm the fine tuning of changing the Feel.

The M12 really is a modern marvel. It will let you mix up any brew you like and serve it back in half a dozen flavors at the touch of a button. If you're good enough to make a living racing little toy cars, then the latency functions might give you an extra .1 and give an edge to move up a rung or two on the ladder. Joe Lunchbox will have a cool new toy to play with in addition to the hundred or so other adjustments he has available to try and work his way out of the B main at the next club race. Clipping a board at speed will cancel out all of the advantages the electronics can give you.
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Old 05-03-2014, 03:18 AM
  #48  
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Originally Posted by frozenpod
Serach came up with this thread.

I tried the reaction time tester, best 183ms, most a touch over 200ms when using the mouse. Around 260ms when using the keyboard. Cool test.

When I tried 2.4 when it first came out I found the latency to be a considerable issues and I switched back imediately to 40Mhz.

Is latency still an issue?
No, which is why everyone uses it now
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Old 05-03-2014, 05:29 AM
  #49  
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Pac steel high end radios haven't changed much since the late 90's. Move to 2.4 and some with telemetry.

I think it is time to replace my 12 year old radio as pots are probably worn and reliability may be an issue.

I don't need any more features as I hardly use the ones I have. What I am concerned about is speed of response/latency and feel.
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Old 05-03-2014, 07:34 AM
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Just do the math!

18 ms latency, at 100km/h.

Distance/time=speed, in meters and seconds.
100km/h is ~33m/s.
after some magic with the formula above gives us, Distance=Spped*time
18 ms=0,018s

0,018*33=0,594m, At 100km/h your car travels almost 0.5 meters before your servos reacts
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Old 05-04-2014, 07:31 AM
  #51  
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Originally Posted by Fliggo
Just do the math!

18 ms latency, at 100km/h.

Distance/time=speed, in meters and seconds.
100km/h is ~33m/s.
after some magic with the formula above gives us, Distance=Spped*time
18 ms=0,018s

0,018*33=0,594m, At 100km/h your car travels almost 0.5 meters before your servos reacts
And it takes your servo about 100ms to actually go to full lock. Five times longer than the response time. And it took your body 200ms to react to what you were seeing.

Puts that latency into perspective - it is a tiny proportion of the cars response time.

We drive our cars by PREDICTING what is going to happen, not by responding to it. Our senses are very finely tuned.

The people that drive by reactions are the beginners that miss every apex by 2m. Latency makes no difference to that.
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Old 05-04-2014, 07:32 AM
  #52  
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Originally Posted by frozenpod
Serach came up with this thread.

I tried the reaction time tester, best 183ms, most a touch over 200ms when using the mouse. Around 260ms when using the keyboard. Cool test.

When I tried 2.4 when it first came out I found the latency to be a considerable issues and I switched back imediately to 40Mhz.


Is latency still an issue?
Spektrum by any chance?
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Old 05-04-2014, 10:38 AM
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Originally Posted by sosidge
We drive our cars by PREDICTING what is going to happen, not by responding to it. Our senses are very finely tuned.
Yes sir. Brain, fingers, car.
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Old 05-04-2014, 03:45 PM
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Originally Posted by sosidge
Spektrum by any chance?
It was quite a few years ago and I tried a few different radios. Certainly futaba and spektrum not sure if I tried airtronics, they are not very popular here.
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Old 07-14-2015, 10:44 AM
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So.....

http://www.rctech.net/forum/14091209-post2058.html
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Old 07-14-2015, 11:28 AM
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I've got one with a .025 deadband...like I've said.... if the wind blows wrong my car takes off... I've just received my new controller today...hopefully its just as fast
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Old 07-14-2015, 11:31 AM
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I'll read the rest of this thread later...right now i'm reading my manual

i did scroll through the first few posts and saw nothing on the particular brand that i have
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Old 07-14-2015, 11:39 AM
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Kongluc I don't mean to be rude but none of your posts on any thread make any kind of sense.
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Old 07-14-2015, 12:13 PM
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Why is that? .025 is what it reads on my computer screen..
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Old 07-14-2015, 12:14 PM
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Thats as high as i can set it...sorry if i use another manufacturer than you
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