2LikesTransmitter latency - does it really matter?
08-28-2012, 07:00 PM
#16
Tech Master
I'm sorry I still find it hard to believe. What measurable difference is their? And I dont mean perceived difference...
Running off road you certainly wouldn't notice it. Running onroad doesn't mean you would notice it. You could have a slight push at initial turn in that you see as a lag in steering input. So the radio must be slow.
There is a huge difference between the response of a computer and the response of an RC car on the ground.
We aren't talking about a cars transmission. Apples and oranges. And we certainly aren't talking about the difference between 10ms and 80ms. 10ms and 40ms was what was refereed to. Less than half what you are referring to.
Like I said what radio manufacturer publishes the latency? How do you know what the latency of the radios are?
And just FYI, because a lot of people get bent out of shape when people disagree with them online, this isn't me arguing with you. This is me debating it and wanting proof. I've wondered the same thing. I have a Futaba 4PL. I certainly couldn't justify the price of a 4PKS because "its faster". I'm sure it is faster. But how much? Its like buying a servo that is .09 vs one thats .08 but paying $100 more for the faster one.
And to make it fair I think a person would also have to take the Tx out of the box without making any adjustments other than trim. Because the features of a radio can make a car feel faster around a track lap time wise. And not all radios have the same features.
Simply too many variables to say its the latency as far as I see it.
Running off road you certainly wouldn't notice it. Running onroad doesn't mean you would notice it. You could have a slight push at initial turn in that you see as a lag in steering input. So the radio must be slow.
There is a huge difference between the response of a computer and the response of an RC car on the ground.
We aren't talking about a cars transmission. Apples and oranges. And we certainly aren't talking about the difference between 10ms and 80ms. 10ms and 40ms was what was refereed to. Less than half what you are referring to.
Like I said what radio manufacturer publishes the latency? How do you know what the latency of the radios are?
And just FYI, because a lot of people get bent out of shape when people disagree with them online, this isn't me arguing with you. This is me debating it and wanting proof. I've wondered the same thing. I have a Futaba 4PL. I certainly couldn't justify the price of a 4PKS because "its faster". I'm sure it is faster. But how much? Its like buying a servo that is .09 vs one thats .08 but paying $100 more for the faster one.
And to make it fair I think a person would also have to take the Tx out of the box without making any adjustments other than trim. Because the features of a radio can make a car feel faster around a track lap time wise. And not all radios have the same features.
Simply too many variables to say its the latency as far as I see it.
At the tracks I frequent, too many racers fall into "it's faster, I can feel it" syndrome IMHO. You simply cannot take away the "human error" element to perceived differences when comparing transmitters. By human error, I mean to say that there are rarely two laps driven exactly the same.
I've noticed no difference between wired and wireless gaming controllers, your internet bandwidth being the main culprit to a good game vs. a bad game.
08-28-2012, 07:08 PM
#17
I'm sorry I still find it hard to believe. What measurable difference is their? And I dont mean perceived difference...
Running off road you certainly wouldn't notice it. Running onroad doesn't mean you would notice it. You could have a slight push at initial turn in that you see as a lag in steering input. So the radio must be slow.
There is a huge difference between the response of a computer and the response of an RC car on the ground.
We aren't talking about a cars transmission. Apples and oranges. And we certainly aren't talking about the difference between 10ms and 80ms. 10ms and 40ms was what was refereed to. Less than half what you are referring to.
Like I said what radio manufacturer publishes the latency? How do you know what the latency of the radios are?
And just FYI, because a lot of people get bent out of shape when people disagree with them online, this isn't me arguing with you. This is me debating it and wanting proof. I've wondered the same thing. I have a Futaba 4PL. I certainly couldn't justify the price of a 4PKS because "its faster". I'm sure it is faster. But how much? Its like buying a servo that is .09 vs one thats .08 but paying $100 more for the faster one.
And to make it fair I think a person would also have to take the Tx out of the box without making any adjustments other than trim. Because the features of a radio can make a car feel faster around a track lap time wise. And not all radios have the same features.
Simply too many variables to say its the latency as far as I see it.
Running off road you certainly wouldn't notice it. Running onroad doesn't mean you would notice it. You could have a slight push at initial turn in that you see as a lag in steering input. So the radio must be slow.
There is a huge difference between the response of a computer and the response of an RC car on the ground.
We aren't talking about a cars transmission. Apples and oranges. And we certainly aren't talking about the difference between 10ms and 80ms. 10ms and 40ms was what was refereed to. Less than half what you are referring to.
Like I said what radio manufacturer publishes the latency? How do you know what the latency of the radios are?
And just FYI, because a lot of people get bent out of shape when people disagree with them online, this isn't me arguing with you. This is me debating it and wanting proof. I've wondered the same thing. I have a Futaba 4PL. I certainly couldn't justify the price of a 4PKS because "its faster". I'm sure it is faster. But how much? Its like buying a servo that is .09 vs one thats .08 but paying $100 more for the faster one.
And to make it fair I think a person would also have to take the Tx out of the box without making any adjustments other than trim. Because the features of a radio can make a car feel faster around a track lap time wise. And not all radios have the same features.
Simply too many variables to say its the latency as far as I see it.
As for published numbers, most manufacturers publish numbers but I wouldn't trust them. It is sort of like battery C numbers. Third party testing has been done on many radios and results published but it mainly seems to be helicopter guys that have both the interest, knowledge and equipment to do the testing.
I have seen testing results on one of the el-crappo cheapfest radios that revealed some startling bad numbers. Not only could the delay be as much as .06 seconds, but it varied anywhere from .02 to .06 seemingly at random. Now tell me, if you're a pro running one inch from the board at every apex and someone hands you a radio with that kind of variance, do you really think you can keep it off those boards while running the same tight lines and laptimes? I sure couldn't. If you want to see those results, dig through the radio sub forum, it's in there somewhere.
08-28-2012, 07:13 PM
#18
Tech Master
iTrader: (13)
FWIW.... I got back into RC last fall after an 8 year break. I got out in summer of 03. At that time I had been using my old trusty Futaba 3PJS. Great radio at the time, I loved it... It took me to many race wins. And, more importantly, I loved the way it felt in my hands. I was just at home with it.
So, when I got back into RC and discovered the new breed of 2.4GHz radios, I decided to convert my 3PJS to 2.4 in an effort to save money on initial expenditures.
I only race on-road... started racing asphalt sedan last fall and progressed to racing, for the most part, only carpet pan-car. Mostly 12th scale. I ran the 3PJS until last April, when I got a new shiny radio. Almost instantly I was able to drive substantially more consistently. I don't think it made me faster in any capacity, in regards to outright lap time... but I felt much more in control and it was far easier to finish an 8-min run without tapping or catching a flapper/board.
I was literally shocked at how big of a difference there was between the two radios. Granted, the 3PJS was released in like 99 or 00, so I obviously knew that technology had improved by leaps and bounds, but it was still surprising. I even went back to the track the following weekend after first trying the new radio, and ran back to back with it and my old 3PJS. Same result.
Dont underestimate the value of a good radio system/transmitter.
So, when I got back into RC and discovered the new breed of 2.4GHz radios, I decided to convert my 3PJS to 2.4 in an effort to save money on initial expenditures.
I only race on-road... started racing asphalt sedan last fall and progressed to racing, for the most part, only carpet pan-car. Mostly 12th scale. I ran the 3PJS until last April, when I got a new shiny radio. Almost instantly I was able to drive substantially more consistently. I don't think it made me faster in any capacity, in regards to outright lap time... but I felt much more in control and it was far easier to finish an 8-min run without tapping or catching a flapper/board.
I was literally shocked at how big of a difference there was between the two radios. Granted, the 3PJS was released in like 99 or 00, so I obviously knew that technology had improved by leaps and bounds, but it was still surprising. I even went back to the track the following weekend after first trying the new radio, and ran back to back with it and my old 3PJS. Same result.
Dont underestimate the value of a good radio system/transmitter.
08-28-2012, 07:18 PM
#19
I could have sworn that I saw an Airtronics video (maybe last year) that gave the exact latency of their transmitters AND compared them to Futaba and Spectrum. Basically, the video shows that while Futaba is a close second, Spectrum was far behind. For some reason, I can't find it now (maybe Futaba and Spektrum complained?). But the chart from that video is still shown in the Airtronics website. Here it is attached. Based on what wingracer posted, it DOES appear that the latency varies within the transmitter as evidenced by this chart from Airtronics.
08-28-2012, 07:35 PM
#20
I could have sworn that I saw an Airtronics video (maybe last year) that gave the exact latency of their transmitters AND compared them to Futaba and Spectrum. Basically, the video shows that while Futaba is a close second, Spectrum was far behind. For some reason, I can't find it now (maybe Futaba and Spektrum complained?). But the chart from that video is still shown in the Airtronics website. Here it is attached. Based on what wingracer posted, it DOES appear that the latency varies within the transmitter as evidenced by this chart from Airtronics.
08-28-2012, 07:50 PM
#21
FWIW.... I got back into RC last fall after an 8 year break. I got out in summer of 03. At that time I had been using my old trusty Futaba 3PJS. Great radio at the time, I loved it... It took me to many race wins. And, more importantly, I loved the way it felt in my hands. I was just at home with it.
So, when I got back into RC and discovered the new breed of 2.4GHz radios, I decided to convert my 3PJS to 2.4 in an effort to save money on initial expenditures.
I only race on-road... started racing asphalt sedan last fall and progressed to racing, for the most part, only carpet pan-car. Mostly 12th scale. I ran the 3PJS until last April, when I got a new shiny radio. Almost instantly I was able to drive substantially more consistently. I don't think it made me faster in any capacity, in regards to outright lap time... but I felt much more in control and it was far easier to finish an 8-min run without tapping or catching a flapper/board.
I was literally shocked at how big of a difference there was between the two radios. Granted, the 3PJS was released in like 99 or 00, so I obviously knew that technology had improved by leaps and bounds, but it was still surprising. I even went back to the track the following weekend after first trying the new radio, and ran back to back with it and my old 3PJS. Same result.
Dont underestimate the value of a good radio system/transmitter.
So, when I got back into RC and discovered the new breed of 2.4GHz radios, I decided to convert my 3PJS to 2.4 in an effort to save money on initial expenditures.
I only race on-road... started racing asphalt sedan last fall and progressed to racing, for the most part, only carpet pan-car. Mostly 12th scale. I ran the 3PJS until last April, when I got a new shiny radio. Almost instantly I was able to drive substantially more consistently. I don't think it made me faster in any capacity, in regards to outright lap time... but I felt much more in control and it was far easier to finish an 8-min run without tapping or catching a flapper/board.
I was literally shocked at how big of a difference there was between the two radios. Granted, the 3PJS was released in like 99 or 00, so I obviously knew that technology had improved by leaps and bounds, but it was still surprising. I even went back to the track the following weekend after first trying the new radio, and ran back to back with it and my old 3PJS. Same result.
Dont underestimate the value of a good radio system/transmitter.
I could have sworn that I saw an Airtronics video (maybe last year) that gave the exact latency of their transmitters AND compared them to Futaba and Spectrum. Basically, the video shows that while Futaba is a close second, Spectrum was far behind. For some reason, I can't find it now (maybe Futaba and Spektrum complained?). But the chart from that video is still shown in the Airtronics website. Here it is attached. Based on what wingracer posted, it DOES appear that the latency varies within the transmitter as evidenced by this chart from Airtronics.
08-28-2012, 08:52 PM
#22
I am by no means a pro, but when using my 3PK I am a half second faster average per lap versus a low end 2.4 gig radio. I am running onroad and carpet on VRC Pro. I know that I could not rely on a radio that does not give consistant performance let alone return to the same centre every time. I do run close to the boards and run multiple laps within .25 seconds or a 25 lap heat without a crash. I agree totally with your post. Although the 3PK is a mid fast radio, it really makes a difference to my driving. I tried two entry level 2.4 ghz radios and both felt vague. You do get what you pay for..
08-28-2012, 09:00 PM
#23
That's not exactly the same thing. Servo speed is how long it takes the servo to move a certain amount, but it STARTS moving essentially instantly (as far as the test goes). Latency is the delay between when you move a control and when the servo STARTS to move. So no matter how fast your servo is, the delay is ALWAYS there. Also, some of the real crappy radios out there are very inconsistent in their latency. It might be just 10ms one time, and 40ms the next. That's not good for consistent driving.
Fortunately, most of the good radios out there are reasonably quick but KO and Airtronics/Sanwa seem to have a bit of an edge. That being said, I still say my FM M11 feels quicker than ANY 2.4 out there, especially compared to Spektrum which is noticeably less responsive.
Fortunately, most of the good radios out there are reasonably quick but KO and Airtronics/Sanwa seem to have a bit of an edge. That being said, I still say my FM M11 feels quicker than ANY 2.4 out there, especially compared to Spektrum which is noticeably less responsive.
08-28-2012, 09:31 PM
#24
He then purchased a KO EX-5 UR, and installed it. Instantly, his car was predictable, and responded almost as quickly as my KO Helios Comp. His laptimes were .2 better right off the bat.
On the same note, my friend's FHSS KO Eurus is even quicker than my Helios. This is not a matter of perception, it is undeniable on a high bite, small carpet track.
Most top drivers use very few of the features on their top of the line transmitters outside of dual rate and endpoint adjustments. A less expensive radio with fewer features would work fine if the manufacturers installed the low latency electronics in the mid level radios.......
All of that being said, You'll see Spektrum, Futaba, Airtronics, and KO on podiums at races around the world.
The radio is by far the most important piece of equipment you'll ever buy in this hobby. IMHO, this is the one area where you ABSOLUTELY buy the highest spec you can afford.
08-28-2012, 10:47 PM
#25
Tech Apprentice
iTrader: (4)
I've been in and out of this hobby since 1994. I never really "believed" in super-high-end radios--until this year. After a 10 year hiatus from R/C I got back into it using my old Futaba FM PCM transmitter. Then, I decided that it looked like I was going fishing every time I went up on the driver's stand with my "outdated" FM radio, I bought a Spektrum DX3C 2.4 gHz. Same car, same setup, and I had to essentially "lead" the steering by 1/4 to 1/2 a car length sooner than when using the FM radio. Not only that, but it was harder to drive smooth since I needed max steering by the time the car got to the point where I needed max steering, so I just cranked the steering wheel all the way at my "new" cornering mark.
After driving a few cars that had K.O.'s Ultra Response system, I decided to get the lowest end model, the EX5, and boy was there a difference. I can drive much smoother in that, at least at my level, that latency is small enough that I can't tell the difference.
Now if only they can build some force-feedback on the wheel so we get a more accurate gauge of front wheel traction...
After driving a few cars that had K.O.'s Ultra Response system, I decided to get the lowest end model, the EX5, and boy was there a difference. I can drive much smoother in that, at least at my level, that latency is small enough that I can't tell the difference.
Now if only they can build some force-feedback on the wheel so we get a more accurate gauge of front wheel traction...
08-28-2012, 10:51 PM
#26
Then we'll be sitting around here discussing force-feedback latency 
08-29-2012, 01:11 AM
#27
Will any of it make you faster though?, to a point probably not, but that must be like everything in RC, just cause it makes the car faster in some way, does not guarantee it will make 'you' faster.
08-29-2012, 01:45 AM
#28
The Sanwa catalogue that lists response times, no idea how much is marketing BS though;
http://www.lrp.cc/fileadmin/FlashKat...g2012_sanwa-e/
I think people are underestimating the difference in the quality of the internal components and how well the internals work when combined, not just thinking about the delay between the transmitter and receiver.
Speaking of speed, I had a conversation at a recent national with Andy Moore, as he uses the same radio as me but with the faster receiver (RX-451R) along with Sanwa Servo's.
I asked if he used Sanwa's SSR mode (fastest) and he said no, it's too fast when set to that !!!
http://www.lrp.cc/fileadmin/FlashKat...g2012_sanwa-e/
I think people are underestimating the difference in the quality of the internal components and how well the internals work when combined, not just thinking about the delay between the transmitter and receiver.
Speaking of speed, I had a conversation at a recent national with Andy Moore, as he uses the same radio as me but with the faster receiver (RX-451R) along with Sanwa Servo's.
I asked if he used Sanwa's SSR mode (fastest) and he said no, it's too fast when set to that !!!
08-29-2012, 03:08 AM
#29
Not too long ago I upgraded my 3PK module from standard Spektrum to FASSST. I can't say I've noticed a difference in how fast my cars react but only that it's more consistant and w/o glitching, but that's another story.
Recently I had a much better driver (than I) drive my car and he was questioning my steering servo because the car was so tight on entry. I was confident in my servo so basically didn't give it much thought after that. I made some changes to the front end and now the car turns much quicker. Certainly, poor handling characteristics can be misinterpreted as slow servo or latency.
08-29-2012, 04:15 AM
#30
I know Ellliot Harper and Andy Moore use the same radio's all the time.