Spektrum 2.4GHz modules and radio gear have become some of the most
innovative products to be introduced in RC in quite some time. Racers
and hobbyists around the world have adopted this breakthrough
technology at an amazing rate. From the time that the original modules
were made available to the general public, the response has been
largely positive, highlighted with the RC Innovation of the Year Award
from Radio Controlled Car Action Magazine. Like any new technology
though, there have been some questions about the performance-
namely the latency of a DSM signal vs. a standard FM or PCM signal.
Latency is the delay that occurs from
the moment an input is given at the transmitter (steering or throttle
movement) to the moment that the servo receives a pulse telling it to
move. Most crystal- based radio systems have a latency between 10-20
milliseconds. That's only .0010-.0020 of a second of latency.
Spektrum's first DSM system added an
additional 5.6m/s of latency into the total system latency of a radio
and its module. Again, we're speaking in terms of thousandths of a
second here. While drivers around the country used the original system
and loved them, there were some who said they could feel the
additional latency in the system and felt it was hampering their
performance.
Listening to the Racers: The Pro
Series is Born
As we've shown, 5.6m/s isn't much. Still, some racers insisted they
could feel a slower reaction time when they equipped their radios with
Spektrum modules. In some instances, the latency could be compensated
for by either turning up throttle or steering exponential rates or by
using faster servos; others simply couldn't make the adjustment.
Spektrum engineers immediately when to work to improve transmission
time while still maintaining a solid RF link for that locked- in feel.
Through testing and development with engineers and top racers such as
Travis
Amezcua,
E.J. Evans, John Adams, and Sonny Brown, it became possible to drop
the latency to only 3m/s while still maintaining a robust RF link. And
so, the Pro Series Spektrum equipment was born.
While they were at it, they
incorporated a few other changes to the Pro Series equipment. One
included a new conformal coating to the circuit boards inside the
receivers to make them waterproof. Another was the new opaque receiver
case that is fuel proof, and which improves durability and
reliability, especially in larger 1/8- scale nitro vehicles. The Pro
Series receivers also feature improved firmware that prevents ESD
(electro- static discharge) issues from the get- go.
What about ESD???
Some racers experienced something that
did not crop up in initial product testing: an electro- static
discharge (ESD) issue. Most of the initial testing on Spektrum Modules
and receivers were done on asphalt, but once the indoor carpet season
began, some ran into issues where the fail- safe on the receiver would
kick in, essentially shutting the car down. Between several testers,
it was found that a firmware upgrade to the receiver would eliminate
the ESD issues. Additionally, it was discovered that the routing of
the transmitter's antenna wire inside the module case placed the wire
directly over the power capacitors. There were times when this
placement of the antenna lead could cause a driver to experience
glitching issues. Again, Spektrum Engineers came up with a fix that
was easy and effective. A new antenna was designed with a longer lead
on it that allowed the wire to be routed around the side of the RF
board instead of over it. All the standard and Pro Series modules and
receivers shipping now feature all of the firmware and antenna
updates. Additionally, those who already purchased Spektrum systems
before May of 2006 can simply send in their system for the firmware
and antenna updates to be made free of charge.
From the mouths of the racers
The ultimate test of any product is how
it performs in the hands of the end users, not the engineers. We've
talked with a number of racers recently to get their take on Spektrum
latency since the introduction of the Pro Series.
Travis Amezcua- Team Losi Factory
Driver; Multi- Time National Champion and IFMAR Worlds Finalist
I
started using the original Spektrum system at the Reedy Truck race in
2004 when it was still in the prototype stages. During the past 2
years, I have used Spektrum modules and receivers and spent many hours
track- testing the system with one of our designers, Mathew Lee. From
the first day I started using Spektrum to today, I've only gone back
to a normal crystal- based radio system once. I did this as an
experiment and to simply try it out again.
When I did, boy did I have a bunch of
glitching problems. Since that last test, I will never go back to
crystals again. With the release of the super- tiny SR3500 micro
receiver, it's now the only receiver I use, and I run it in every car
that I race. From 1/8 gas off- road to 1/10 electric off- road, the
new SR3500 is bulletproof, both in terms of durability and signal
quality. Since I have upgraded my radio to Spektrum 2.4GHz DSM
equipment, I've never once had any kind of a radio problem. And for
those who think that Spektrum slows you down, I have won more than a
few National Championships with Spektrum equipment in my cars. The
proof is in the results.
Todd Hodge- Team Manager, Team Losi
I
was lucky enough to be one of the first testers for the Spektrum
equipment. I felt it was the greatest and most innovative idea for an
RC product that had ever been designed. As we headed into the carpet
season with our touring cars, we felt that there were some potential
problems with the latency. We changed back to our crystal- based
equipment soon after that.
Recently, however, I was introduced to
the new Spektrum Pro Series modules and the new Spektrum SR3500 Micro
Receiver. While attending the IFMAR Touring Car World Championships in
Italy, I was experiencing major glitching problems and needed a fix
fast. I installed the new Spektrum Pro Series Module in my JR Z- 1 and
SR3500 Micro Receiver in my Team Losi JRX- S Type R touring car and
never looked back. It was awesome. I never experienced another problem
the rest of the weekend. Back in the States, I have continued to use
the Spektrum Pro Series on carpet and found that it works flawlessly.
It has no latency issues that I can feel. I will be running the entire
season with the new Spektrum Pro Series equipment to ensure the proven
preciseness that has been incorporated into the new Spektrum Pro
Series Module and SR3500 Micro Receiver.
Jon Kerr- Team Schumacher USA Factory
Driver
I
first used one of the original M8 Spektrum module and receiver units
in 2005 for the Reedy Race of Champions. I've had radio issues at the
Tamiya America facility in the past, but this time I didn't have a
single glitch all week. As a serious competitor, however, I could feel
the slight latency in the system on the track and couldn't adapt my
driving style to overcome it. Several months later, I returned to
using crystals and my results improved once I did.
With these previous experiences, I was
more than a little skeptical to try the Pro Series system when it was
released. After talking to a number of other racers, I decided to give
Spektrum a try again and I'm very glad I did. Now I feel no delays
whatsoever when I am on track. If anything, my car feels more
responsive than it did with crystals. I'm able to enjoy the benefits
Spektrum offers and still be confident that I'm not going to have any
radio issues. This is how radio systems should be made.
Sonny Brown- 2005 Snowbirds 1/12 Scale
Oval Champion, Former ΒΌ Scale Champion and Race Promoter of the
Brushless Racing League
As
a racer, I've been using the Spektrum system in competition for almost
two years now and have never had an issue with my car feeling non-
responsive. With the speed of today's modified oval cars you need to
feel connected every time you hit the track. The Spektrum system I use
in combination with my JR Z- 1 radio delivers the confident
comfortable feel I'm looking for time after time.
As a race manager, the Spektrum system
is one of the greatest innovations to come along in years. It simply
speeds up the race program. Fewer frequency conflicts cause after
qualifying re- sorts cause less time delays and help keep my race
programs running smooth.
David Weir- 2003 Tamiya Championship
Series Mini National Champion
When
I first read about the Spektrum system release, I was eager to give it
a try, as it sounded almost too good to be true- no crystals and no
conflicts to worry about. All of my expectations were met by the
original Spektrum performance. No glitches, no conflicts, just walk
right up to the drivers stand and turn it on. As I race primarily on
carpet in a building with fluorescent lights, WiFi, and cordless
phones, I was pleased to find virtually no problems. The sole issue I
experienced on rare occasions was due to the ESD issue. Thankfully,
the problem was quickly solved by the timely (and free) software
update.
When the Spektrum Pro Series was
announced, I was skeptical about the claims of reduced latency, but
decided to give it a try. After a year of racing with the original
Spektrum system, I had noticed just a slight latency in the system,
something I only noticed "at the tone" start of the race.
While some might say you shouldn't be able to tell the few
microseconds difference, I immediately noticed that, with the Spektrum
Pro Series equipment, I had a much more immediate response on the
tone. Until I became accustomed to the faster response, I also found
myself turning in just a touch early to each corner, but after just a
couple of battery packs I adjusted to the faster response time.
As I love to race Tamiya Mini Coopers,
I was also very impressed with the new SR3500 micro receiver- a true
work of art. It is so small that I can now bury the micro receiver and
my speed control down low and within the small confines of the mini
chassis for a nice low center of gravity and neat appearance. The 2006
TCS Nationals had over 150 drivers participating, and it was a
pleasure to never wait for a frequency clip, never have a glitch, and
be fully confident of radio control of my car. I'll never go back to
crystals again.
Rapid Response
As
for my personal experience, I race at a variety of events from local
club races, the US Touring Car Championships (The Novak Race), to the
Tamiya Championship Series regional and national events. I started
running the original Spektrum system during the summer of 2005, first
in my Sportwerks Mayhem, then in my Tamiya TA- 05. Now every car I own
has Spektrum equipment.
I have attended the Tamiya Nationals
every year since 1999 in Aliso Viejo, California at Tamiya's
headquarters. The track is known for having radio issues, and I have
had glitching issues there in the past. The 2005 Nats was the first
big race I ran a Spektrum system in and it was pretty sweet. I never
had to wait for a frequency clip in all of practice, and I never had a
single hit.
A few months later, I was able to test
the Pro Series equipment in both my brushless and stock rubber Team
Losi JRX- S cars at the 2006 Novak Race. I didn't realize why at the
time, but I kept turning in early for corners. It was the weirdest
thing and I couldn't figure it out until after the event. I had
adjusted my driving style to drive around the latency without thinking
about it, and one of the adjustments was to turn in earlier for
corners and turn up my expo.
I have since adjusted to the faster
response time and love my Pro Series equipment. I also like that I can
still use my SR3000 receivers in my cars I just play around with, so I
can still get use out of my original equipment. Oh, and at the 2006
Tamiya Nats, I also ran a Pro Series Module with the new SR3500 Micro
Receiver. Again, I practiced when I wanted, never waited for a clip,
and never had a radio hit. In fact, I never thought about my radio or
frequency once all week. It was super dialed.
There can always be confusion,
misconceptions, and otherwise bad information in the responses heard
when a new technology is introduced. When it comes to Spektrum
technology, Spektrum is a fluid sort of product and the development
never ceases. A radio system's speed and response time is all
relative. With improved latency and a broad range of products
available, there's no good reason not to upgrade to Spektrum
equipment. After all, the guy who just passed you probably did.