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Old 07-17-2006, 03:00 AM   #61
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Originally Posted by pcar951
Thanks for the link, interesting! I need to say that I have never experienced any problems with My Spektum systems other than possibly static discharge on carpet causing shut down. I followed the MFGs specs and re-routed the antenna wire in the case. I also bent my chassis antenna tube at 90 degrees keeping it inside the body.....problem solved, period. I'm thinking that the acid test for glitches, is going to be the IIC in a couple of months.
Jim C.

Last year at IIC not only did I not have any issues with my DSM, but didn't hear of anyone having issues. Never having driven on carpet before I broke and crashed a lot, once so bad my dsm reciever came out of my car and dangled for half a lap. Pooped it back in there never had an issue.

Still using the same reciever, never been updated or anything, never used a capicitor on it either, I have yet to expierence an issue.

KO helios with spektrem-
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Old 07-17-2006, 11:37 AM   #62
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Quote:
Originally Posted by Chris Adams
Thanks, that is what I was worried about...especially since I just bought the new mini reciever that cant take a servo, speedcontroller, transponder and capacitor at the same time .
Chris - I really dont think you have anything to worry about. I dont think anyone had issues with novak esc's. Before you start getting rid of everything test it. see how it works for you. if your still worried get a Y splitter and a capacitor. Or go back to you old stuff.

All I can say is I think I am going to buy a new GTX, micro DSM receiver and I wont know what to do with all the space on my chassis.
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Old 07-17-2006, 12:36 PM   #63
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I just switched from using the original Spektrum to the newest Spektrum Pro Tranmitter module and micro receiver. The original has a reported 5.6 ms latency, the newest cuts 2.6 ms off of that. Both were used in my Futaba 3PK.

In normal driving, I personally did not notice the 5.6 ms latency. When I switched to the Pro combination, my first couple runs were not pretty - kept just ticking the plastic corners of the layout - obviously, I had become accustomed to one degree of delay with the original Spektrum, and the new system was quicker, leading me to initiate a turn just a tad earlier than I needed to. A few battery packs through the system and now I'm used to the quicker response, no more nicked corners (or at least back down to my normal #).

Where I do notice a definite difference between the original Spektrum and the Pro combo Spektrum is at the very start of a race. It was the primary reason I decided to try the upgrade. With the original Spektrum, "on the tone" starts seemed to look like I was asleep at the switch, starting from the dead stop just a bit slower than others. I came to suspect that it might be the Spektrum latency, and hoped that upgrading would make a difference. That is the one time in a race where you can't "train" yourself as to the latency issue as you can with the running of the rest of the race.

I can definitely tell the difference now using the Pro combo, as I am no longer looking like I am asleep at the tone, I now take off at the race start just like everyone else. No longer having a backup behind me. Makes for a much better cleaner start of the race.

I now love my Spektrum more than ever. NO crystals, no freq conflicts, no wait for clear frequency for practice, etc.

Bottom line: if you have the choice between the original Spektrum and the Pro combination, it is worth it to go with the Pro. If you have the original Spektrum and are considering upgrading, that is a closer question given you have to spend another $175 (but can then sell your old system to someone else).
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Old 07-17-2006, 12:46 PM   #64
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We "feel" our cars by seeing them and how they react to our inputs. Its all a product of hand to eye coordination.

That said, science has shown that it takes 20-40 miliseconds for a simple visual stimulus to be transmitted to the brain for processing. This does not include reaction time (reported to be 220ms for simple known reactions), nor does it include decision time, and the time it takes the brain to transmit the result back to your hands to be performed. So needless to say...We cannot "feel" the 5ms difference.

Anyone that thinks otherwise is wrong, beyond the effects of psyching themselves out.
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Old 07-17-2006, 01:09 PM   #65
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Quote:
Originally Posted by JKA
We "feel" our cars by seeing them and how they react to our inputs. Its all a product of hand to eye coordination.

That said, science has shown that it takes 20-40 miliseconds for a simple visual stimulus to be transmitted to the brain for processing. This does not include reaction time (reported to be 220ms for simple known reactions), nor does it include decision time, and the time it takes the brain to transmit the result back to your hands to be performed. So needless to say...We cannot "feel" the 5ms difference.

Anyone that thinks otherwise is wrong, beyond the effects of psyching themselves out.
If I am doing my math right, 220 ms is 2/10th's of a second. I would certainly think RC drivers react quicker than that.
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Old 07-17-2006, 01:41 PM   #66
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Originally Posted by minidriver
If I am doing my math right, 220 ms is 2/10th's of a second. I would certainly think RC drivers react quicker than that.

Go try it... you might be suprised. We give ourselves too much credit.

http://www.getyourwebsitehere.com/jswb/rttest01.html
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Old 07-17-2006, 02:12 PM   #67
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You'd be hard-pressed to see .005 difference in reaction time in two 1:1 drag cars with a super slo-mo video replay.

EDIT:

.41, .41, .41, .48 (distracted...LOL), .42, .426 average...is that good? I'm nothing if not consistent.
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Old 07-17-2006, 02:15 PM   #68
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I was talking about this very same subject (reaction time etc, not dsm) to a friend of mine who is a Neuroscience Phd cadidate. We were talking about the almost physical sensation you get from video racing games.

Basically the above is true in regards to processing new, unknown data. That said, when working with repetitive tasks and familiar things, its a whole new ball game. When we turn in to a corner it is not reaction time. You have turned in to the same corner for X number of laps. Your brain develops connections associated with all the stimuli related to that corner. Thats why you feel locked in and in control once you are comfortable on a track, and somewhat disconnected while you are still learning.

Also, those connections create the almost physical sensations of push, oversteer etc. Once our brains adapt to the course and car, when the car reacts different from the norm based on our inputs, and the car isn't where its supposed to be based on previous experience, our brain lets us know something is funky and we can almost feel the handling condition present. This is true of things like video games also.

So it is entirely possible, that when switching from FM to DSM, tiny, almost inperceptible differences in response could translate in to a palpable difference in the way your car feels. It does not necessarily mean it is slower, worse etc. It is possible that you could feel a difference though.
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Old 07-17-2006, 02:18 PM   #69
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Quote:
Originally Posted by JKA
Go try it... you might be suprised. We give ourselves too much credit.

http://www.getyourwebsitehere.com/jswb/rttest01.html
Cool... Maybe I shouldn't post this but. Is an ave of .187 slow for a 36 year old??
E
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Old 07-17-2006, 02:24 PM   #70
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I got it down to .33 with another button...instead of the mousepad. Maybe THIS is why I suck at racing. I gotta get a tricked-out mouse and connect through the Cat-5 instead of the wireless...
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Old 07-17-2006, 02:52 PM   #71
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This is 2 questions really.

1.) Can a human being perceive a 5ms difference visually.

Techically, yes. The speed of light in the distance between your car and the eyeball will always be a limiting factor. Thats pretty quick though. The rate at which your brain processes those transactions, and the time it takes your muscle system to actuate is a far more interesting and variable number per person.

2.) Is it practical to have that data?

For most people, likely not. Take a quick test: http://www.topendsports.com/testing/reaction-timer.htm
Most people are going to end up with something around .1 to .5 seconds to actuate a manual response.

That means, your average human body is going to add in between 100 and 500ms of lag to any driving correction you may make. More if you are not concentrating well.

So keep the big picture in mind when trying to guaging 5ms as a performance loss.
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Old 07-17-2006, 05:05 PM   #72
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See I had the original system and maybe this is why I noticedsome difference fromHRS to spektrum. Hearing good things about the new system makes me want to try it again. I never had but a few glitches on the old system after a year of use. To tell you the truth I don't recall getting much radio interference with my fm system either but I do like the idea of setting trims ect in the pits without needing to hook up a wire to my transmitter.

As far as all the stuff about our brains haha, all I know is what I see and feel and that is good enough for me haha to much technical jargon for my brain
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Old 07-17-2006, 05:07 PM   #73
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Quote:
Originally Posted by Jon3
This is 2 questions really.

1.) Can a human being perceive a 5ms difference visually.

Techically, yes. The speed of light in the distance between your car and the eyeball will always be a limiting factor. Thats pretty quick though. The rate at which your brain processes those transactions, and the time it takes your muscle system to actuate is a far more interesting and variable number per person.

2.) Is it practical to have that data?

For most people, likely not. Take a quick test: http://www.topendsports.com/testing/reaction-timer.htm
Most people are going to end up with something around .1 to .5 seconds to actuate a manual response.

That means, your average human body is going to add in between 100 and 500ms of lag to any driving correction you may make. More if you are not concentrating well.

So keep the big picture in mind when trying to guaging 5ms as a performance loss.
HERE IT IS FELLOW RACERS......THE REAL SCHIZ!!!!

If you're not even as fast as your existing equipment, what the frick does it matter, right!

Use what ever system that gives you the least grief. And for me, thats DSM
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Old 07-17-2006, 05:34 PM   #74
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Quote:
Originally Posted by Jon3

For most people, likely not. Take a quick test: http://www.topendsports.com/testing/reaction-timer.htm
Most people are going to end up with something around .1 to .5 seconds to actuate a manual response.
Got a .109 second PB
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Old 07-17-2006, 06:00 PM   #75
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Quote:
Originally Posted by eforer
I was talking about this very same subject (reaction time etc, not dsm) to a friend of mine who is a Neuroscience Phd cadidate. We were talking about the almost physical sensation you get from video racing games.

Basically the above is true in regards to processing new, unknown data. That said, when working with repetitive tasks and familiar things, its a whole new ball game. When we turn in to a corner it is not reaction time. You have turned in to the same corner for X number of laps. Your brain develops connections associated with all the stimuli related to that corner. Thats why you feel locked in and in control once you are comfortable on a track, and somewhat disconnected while you are still learning.

Also, those connections create the almost physical sensations of push, oversteer etc. Once our brains adapt to the course and car, when the car reacts different from the norm based on our inputs, and the car isn't where its supposed to be based on previous experience, our brain lets us know something is funky and we can almost feel the handling condition present. This is true of things like video games also.

So it is entirely possible, that when switching from FM to DSM, tiny, almost inperceptible differences in response could translate in to a palpable difference in the way your car feels. It does not necessarily mean it is slower, worse etc. It is possible that you could feel a difference though.
That makes a lot of sense, and is pretty interesting to boot. And unless I completely misunderstood, it somewhat proves that the speed of the radio is only an issue if you change it (switch to or from DSM). Thus as far as latency is concerned there is no advantage to having ultra fast HRS etc.
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