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MattHiggins
02-09-2007, 05:29 PM
http://209.2.68.15:8011/pics/novak2.jpg

From Novak:
NOVAK COVERS THE SPREAD
While spread spectrum or DSM (Digital Spectrum Modulation) technology has only been in the R/C industry for a few years, it has gained quite a following due to its ability to offer racers freedom from radio interference. Novak is the first to acknowledge this with products specifically designed to take full advantage of DSM technology. Novak’s response is the first speed controls optimized for spread spectrum transmitters: the #1711 GTB Spread Spectrum Brushless/brush ESC and the #1715 GTB 4-Cell Spread Spectrum Brushless/Brush ESC.
Always a technological leader, Novak has upgraded the GTB ESC to work with spread spectrum systems from manufacturers such as Spektrum™, Nomadio™, and Futaba™. Since DSM uses a much higher frequency, 2.4Ghz to be precise, this has allowed Novak to finally unleash the full potential of the GTB speed control. Both new GTB models now have significantly faster MOSFET switching speeds, which provide improved performance and cooler operating temperatures. In short, the ESC gets power and increased operational efficiency at the same time!
MOSFET switching speed is a key feature for the spread spectrum specific GTBs. The MOSFET switching speed is not just the frequency of the ESC, it’s actually how fast the ESC’s MOSFETs turn on and off. With regular radios, ESCs are limited by how fast they switch on and off. If it switches too fast, the radio system will experience interference. With DSM this is not an issue. Novak Engineers have been able to take full advantage of this great new technology and now offer a high-speed switching GTB for all the spread spectrum/DSM users. While users should not expect a huge difference in feel or driving style, they will notice improved motor operation and lower ESC operating temperatures.
While Novak’s two new GTB models have been equipped to work with spread spectrum technology, all of the same great Novak features have been left intact, including six throttle profiles (5 brushless, 1 brushed). These versatile ESCs are compatible with all Novak 540-size sensored brushless motors, and have no brushed motor limit. A user-friendly interface along with 4 different color status LEDs make programming the GTB extremely easy. The brushless mode has 4 adjustable parameters, including Minimum Brake, Drag Brake, Deadband, and Minimum Drive. The brushed mode is fully programmable with all of the adjustments of the brushless mode, plus adjustable Drive Frequency. The GTB also uses exclusive lightweight MOSFET technology, which have the lowest ‘RDS On’ value, and which allows the speed control to have the highest power density.
Both the #1711 GTB Spread Spectrum Brushless/Brush ESC and the #1715 GTB 4-Cell Spread Spectrum Brushless/Brush ESC are scheduled to ship March 2007. The list price is $325.
GTB SPREAD SPECTRUM BRUSHLESS ESC FEATURES:
 Optimized for use with Spread Spectrum Transmitters for improved performance and cooler operating temperatures
 Compatible with brushless and brushed motors
 Includes five brushless throttle profiles (#1711 has 3 forward/brake and 2 w/reverse; #1715 has 4 forward/brake specific for 4-cell racing and 1 w/reverse)
 Includes one fully-adjustable brushed throttle profile (forward/brake)
 4 Adjustable Parameters: Minimum Brake, Drag Brake, Dead Band, and Minimum Drive, as well as Drive Frequency (In Brushed Mode Only)
 User-friendly programming interface with 4 status LEDs
 Novak’s One-Touch Set-Up (still the easiest)
 Gold-Plated PCB Direct-Solder Wiring Tabs
 User-replaceable input and switch harness (#1711 is plug-in style; #1715 is re-solderable)
 Thermal Overload Protection
 Water-resistant case
 Factory-installed power capacitor module
 #1711 includes clear cooling fan (30x30x8mm) mounted on factory-installed heat sink
 Radio Priority Circuitry
 Polar Drive Circuitry
 Designed, manufactured, and tested in the USA

GTB SPREAD SPECTRUM BRUSHLESS ESC SPECS:
Forward/Reverse Forward/Brake/Reverse (Brushed mode is Forward/Reverse)
Input Voltage 4-6 cells (#1711); 4 cells (#1715) Ni-Cd/Ni-MH cells (1.2V/cell or
4.8-72. total volts)
On-Resistance 0.00040 ohms (brushless)*, 0.00013 ohms (brushed)*
Footprint 1.16” x 1.49” (29.5 x 37.8 mm)
Weight 1.36 oz / 38.6 g (#1711); 1.01 oz. / 28.5 g (#1715)
Rated Current 540 amps per phase (brushless)*, 1620 amps (brushed)*
Braking Current 540 amps per phase (brushless)*, 1620 amps (brushed)*
Power Wires 16-GA (#1711); 14-GA (#1715)
BEC 6.0 volt/3.0 amp
Motor Limit Any Novak 540-size brushless motor; No brushed motor limit
Discrete Steps 1024 Forward; 1024 Reverse
Battery Plug None
Motor Plug None
Drive Profiles 6 (5 brushless, 1 brushed)
Status LEDs 4
*Mosfet rating at 25 degrees Celsius junction temperature
Spektrum is a registered trademark of Horizon Hobby, Inc.; Nomadio is a registered trademark of Nomadio Inc.; Futaba is a registered trademark of Futaba Corporation.

metalry101
02-10-2007, 12:46 AM
That's pretty cool, but why with all the increased efficiency, does it still need the cooling fan? Could it be because it's still not as efficient as the Castle Creations Mamba Max?

Craps
02-10-2007, 03:01 AM
We use the current version Novak GTB with the 5.5 motor in stadium turcks in 20 minute mains without the fan on the ESC.

The Mamba is a great bashing system, but for racing you better use a sensored system to get accurate smooth throttle response that a sensorless system can not give you.

If you are a racer you better use the Novak GTB or you will get beat by somebody who is using one!

InspGadgt
02-10-2007, 03:20 PM
ESCs were using higher frequencies then they are now but were lowered not because of radio interferrence but to get more punch out of them. Higher frequencies were smoother but felt mushy while lower is more punchy. So why go back to higher? Is the frequency effect felt differently on brushless then it is on brushed?

ronb
02-10-2007, 05:38 PM
Will this new ESC be available immediately with the new SS Pro motors? I'd be interested in geting a spread spectrum ESC with the SS Pro 13.5 as a combo!!!

NovakTwo
02-10-2007, 06:19 PM
Will this new ESC be available immediately with the new SS Pro motors? I'd be interested in geting a spread spectrum ESC with the SS Pro 13.5 as a combo!!!

Initially, the Spread Spectrum GTBs will be sold individually, not in systems.

If there is enough demand, some systems may be offered later.

jamesbernatchez
02-10-2007, 07:44 PM
We use the current version Novak GTB with the 5.5 motor in stadium turcks in 20 minute mains without the fan on the ESC.

The Mamba is a great bashing system, but for racing you better use a sensored system to get accurate smooth throttle response that a sensorless system can not give you.

If you are a racer you better use the Novak GTB or you will get beat by somebody who is using one!


Im running a Mamba Maxx in my T4 and BJ4 as is the owner of the track. We dont have problems finishing. In fact I used to race wtih two Novak GTB's w/ 5.5 motors, in my XX4 and XXX-CR. I prefer the Mamba systems not just for the programability but for the fact its more efficient. I temped my BJ4 after a 6 minute run and the esc was at 150 and the motor was at 135. My Novak w/ fan after a 5 minute heat was usually a bit higher on the esc and a good 170 or so on the motor. And that is with proper gearing.


Im sticking with CC :D

Craps
02-11-2007, 01:11 AM
Im running a Mamba Maxx in my T4 and BJ4 as is the owner of the track. We dont have problems finishing. In fact I used to race wtih two Novak GTB's w/ 5.5 motors, in my XX4 and XXX-CR. I prefer the Mamba systems not just for the programability but for the fact its more efficient. I temped my BJ4 after a 6 minute run and the esc was at 150 and the motor was at 135. My Novak w/ fan after a 5 minute heat was usually a bit higher on the esc and a good 170 or so on the motor. And that is with proper gearing.


Im sticking with CC :D

I raced with a Schulze U-Force 75 ESC and the Plettenberg Extreme motor in my T-4 up until Novak came out with the sintered rotor upgrade for the Velociti motors that makes them the best system for the money you can buy. Until the sintered rotor upgrade came out, you could not have given me the Novak system due to problems with heat and runtimes. With the sintered rotor you can race for over 20 minutes+ nonstop all the time without the fan on the ESC.

There was 2 trucks that made it to the "A" main where I raced at today with the Mambas that were not in the top 5 with the Novak systems and that was a 20 minute long main as we typically race in every week.

We have been racing using 8000 mah li-pos in my area for over 3 years now in 20 to 30 minute long electric mains using the latest brushless systems along with using different combos using brushed motors and the top racers are discovering for the money, the Novak GTB with Velociti motor and sintered rotor are a tough combo to beat. The 20+ minute electric racing on regular basis is the true test for any system and the Novak passes it now with flying colors.

I am sticking with Novak! Sensorless can not match sensored for being smooth!

scoob
02-11-2007, 07:58 PM
Now Tim, you know one of those A-main drivers was me and I'm not the best representative for the Mamba performance. Besides, you finished 5th and I was 6th. Of course, you lapped me twice but... ;)

The Mamba is VERY smooth for sensorless, it suprised me really but I admit my old Novak was just a touch smoother.

I agree that the Novak is hard to beat now with the heat issues gone. It's my luck that I switched to a Mamba right before the sintered rotors were released. I'm going to stick with it though because the difference is very small and I want to make sure the heat issues with GTB don't return this summer when it's 90 degrees. If they don't, I'll probably go back to a Novak because I need every advantage I can get. :)

had a blast yesterday. 20 minute electric races rule!

Craps
02-11-2007, 08:11 PM
Gary
I will have to admit the computer link up with the Mamba sounds alot better than the Schulze DOS version of setup. Sounds like you and Carl are giving it the test.

Had a blast also and 20 minute electric mains rule!!!!!

Going to Wilkesboro next Saturday to race with Brad and Co up there. Come on up!

Don't forget The Farm II's big Electric Pro Truck debut is March 17th and you need to get pre-entered soon before the 150 total entry limit is met.

See ya soon!

rocketron
02-13-2007, 06:51 PM
ESCs were using higher frequencies then they are now but were lowered not because of radio interferrence but to get more punch out of them. Higher frequencies were smoother but felt mushy while lower is more punchy. So why go back to higher? Is the frequency effect felt differently on brushless then it is on brushed?

your talking about the drive frequency not the operational frequency :D

CharlieS
02-13-2007, 08:46 PM
Drive frequency is different then the "switching" used to Create that drive frequency. You can have any drive frequency and many diffferent switching rates as well.

We leave the fans on, so if you want to take good care of your stuff you can. Many people run daily with out them, many leave it on for added protection.

I'm glad everyone is happy with their Mambas.... :)

Hey Craps, How hard is it to adjust the settings on your GTB??? Isn't it nice to be able to just adjust them at the track and not lug out your PC??

pinolelst
02-13-2007, 09:14 PM
I'm glad everyone is happy with their Mambas.... :)

Hey Craps, How hard is it to adjust the settings on your GTB??? Isn't it nice to be able to just adjust them at the track and not lug out your PC??

Hey...I have both Novak and Castle Creations systems and both give me good service.One thing though..you're implying that the mamba can't be programmed without lugging out a PC.You can still program via beeps and xmitter movements just like just about any other esc.It's just nice and convenient to use the PC if at hand ;)

pinolelst :wave:

Craps
02-14-2007, 07:32 AM
Charlie
You are so right and the smooth throttle response of sensored can't be beat especially when that track drys out and gets real slick with low traction.

Can't wait to get the new Spread Spektrum GTB and in fact we have been playing telephone tag yesterday with the voice mail. Call me!

Tim H

PS. I need to talk to you about the big Pro Truck races at the Farm II also. We are getting alot of pre entries for the class with a 20 minute main and even some AE team drivers.

jamesbernatchez
02-15-2007, 01:58 PM
Ive had 2 Novak 5800 SS systems, 2 Novak GTB 5.5 systems, Mamba Max 5700 system, and a Mamba Max 4600 system. Ive never had a problem with any of the systems.

The Novaks never thermaled on me with or without the fan, but the Mamba seems to run cooler. Both brands are very good and you cant go wrong with either, its just right now I like the fact I can program the mambas, save a few different profiles on the computer, and swap them by simply hooking the esc up to the computer, which is awesome. Im sick of watching lights, listening to beeps, typing in the access code, and do a retina scan in order to change profiles. If you dont want to lug a laptop around or cant use one at home than this shouldnt make your decision on either system.

One other factor I like is the fact the Mamba has lipo cutoff built in. Ive ran the Novak with lipo and as soon as power decreased I just stopped but its nice not having to worry about it.

The deciding factor for me.......was price. Ive picked up both my Mambas anywhere from $20-40 cheaper than the Novaks. Ive heard of problems with both brands, which is going to happen in electronics, so read up on both systems and see what one fits you better. For now Ill stick with the Mamba :)

Why come out with a new esc without lipo cutoff? I know its not legel to run lipo but most club racers are.

ElectricThunder
02-15-2007, 04:22 PM
IMO, mamba vs. novak is apples vs. oranges. I have both (not the GTB; an HV ESC running an SS5800...close enough:p), and I have to say that overall, I prefer the "feel" of the Novak. For adjustability, the mamba takes the cake hands down. For reliability, they're tied (neither has failed). In terms of power...mamba gets the win (then again, I'm comparing an SS5800 with a velociti rotor, so no real comparison....anyone wanna lend me a 6.5 to test?:D).

If you race, I think the Novak would be best. If you bash, I think the mamba would be best. If you do both....well...decide which is your priority and go from there. :)

jamesbernatchez
02-15-2007, 05:20 PM
IMO, mamba vs. novak is apples vs. oranges.

I dont see how that makes much sense. Both are used for the same thing and have similar features. They are competing against each other to a degree.

The one thing I will give to novak is the fact that their motors are ROAR approved, which means they are allowed at bigger races.

The thing is im only using my brushless systems to race with and i think the mamba is fine for racing. I dont see why people say its more for bashing. I have no cogging issues whatsoever w/ 3600 Nimh cells and the throttle is ultra smooth. Im running one in my BJ4 and the other in my new T4 and feel they are well suited to the vehicle and track.

As far as power....I think the Mamba wins hands down(running the same battery). My 5700 in my BJ4 is as fast if not faster than a novak 6.5/5.5(cant remember which he is running) in the same vehicle.Plus all my settings are pretty mild. Hell, my 4600 in the T4 was keeping up with a BJ4 w/ the 5700 on the back straight. I think you can push these motors more than the Novak's IMO. I noticed at my track(Wolcott Hobby) it seems more people are running the Mamba system than the Novak. It could just be my imagination :D

I think this is a neverending battle between the two. They are both good, at the moment the Mamba has more adjustability like ElectricThunder said, both can be very fast, do well in racers and bashers, and are priced well(the mamba a little better than the novak) Ive owned many, many products from both companies and would gladly give my money to either.

ElectricThunder
02-15-2007, 06:18 PM
On a competitive level in organizations such as ROAR and IFMAR, the Novaks aren't competing with the mamba system. They're competing with other sensored systems that are legal like the LRPs, GMs, and soon to be Orions.

On a grander scale in the bashing and club racing world, yes they compete.

But I say it's apples to oranges in terms of the technology used. The Novaks are sensored, the motors are built to a very different spec than the CM mambas (stators, wind types, rotors, etc.), and the Novaks were designed for the purpose of racing (evidenced by the 4-6 cell limit, and all the fun "race" adjustments that can be programmed in, but the mamba does have those adjustments too, so don't get me wrong). I think the Mamba was designed more or less to be the "jack of all trades" in that it's one helluva basher, but it can still race pretty well too. It's still no sensored setup from my experiences though (I drove my Novak for at least 1 or 2 years before I got a mamba, and I could immediately tell the difference in the "feel" of the throttle).

Just my opinion though.

I think the "best" ESC out on the market right now in terms of versatility is the Graupner Genius 80. Can run sensorless motors, or if you run sensored, it has a little sensor port too! All you do is select whether you're running sensored or sensorless. Probably has most of the same features as the mamba, except for having a little USB port.

chickhicks
02-18-2007, 02:34 PM
any chance you would ever go to a blue heatsink
I cant stand purple
mabby I am just too critical but almost all the cars made seem to be blue
at least the ones i like, I don't feel like starting a anodizing war
my brand is better bla bla bla
You could always have them as a option and suckers like me would buy them
kachinga

ElectricThunder
02-18-2007, 04:19 PM
any chance you would ever go to a blue heatsink
I cant stand purple
mabby I am just too critical but almost all the cars made seem to be blue
at least the ones i like, I don't feel like starting a anodizing war
my brand is better bla bla bla
You could always have them as a option and suckers like me would buy them
kachinga
Blue is LRP. There'd be an identity crisis :eek: . The ESC wouldn't know what it was...:D :D (Purple and Orange has become the Novak "marker" as well...)

I'd like to see an orange annodized heatsink though. That'd be kinda cool, and something "different".

Craps
02-18-2007, 08:02 PM
Purple...blue heat sinks.....jeeezzz, put the body back on and let's race!!!!! :driving: :driving: :D :D :D

MartinRacing
02-18-2007, 08:29 PM
Hey Craps, brushed motors work great. lol

pinolelst
02-18-2007, 10:31 PM
Hey Craps, brushed motors work great. lol

Yeah keep those brushed motors.Someday they may be worth some money as collectibles :p :D


pinolelst :wave:

scoob
02-19-2007, 12:40 AM
Martin runs brushed mods in 20 minute mains. I don't know how he does it.

It doesn't matter, he'll never be as fast as me and Craps. :D :D :driving: :driving:

Craps
02-19-2007, 03:47 AM
I am curious to see how Martin's brushed motor works at a huge track like the Farm II next month in a 20 minute main. The Farm II in a 20 minute main will be the ultimate test for any system weather it is brushed or brushless.

Stay tuned!

PS. The Carolinas point series Electric Pro Truck class with 20 minute mains with Novak GTBs and Velociti brushless motors finishing 1-2-3.

WhoMe
02-20-2007, 11:38 PM
Does anyone have a release date on this?

Steve Weiss
03-05-2007, 07:15 PM
I have read through most of the posts here and wanted to make some points that I feel get overlooked on behalf of the GTB.

We designed the GTB to be a racing speed control, which means all the adjustments you need in as small and light a package as possible... yet people still say that the Mamba is "far more programmable" than the GTB.

Let's take a look at the adjustments that are possible in both ESCs and see how big this gap really is! :teacher:

Choice Between FWD/Brake/Reverse:

Both the GTB and the Mamba Max have adjustments for whether or not you want brakes or brakes/reverse.

We allow for separate profiles which are easily accessible (if you can press and hold a button for a few seconds) so that you can go between a "bashing/practicing" profile and a racing profile trackside in just seconds.

Brake Amount:

The Mamba gives you 4 settings which you can select via the ESC which essentially just change the brake endpoint.

Since most radios now come equiped with some sort of end point adjustment in them we felt it was easier to simply let the user adjust their brake endpoints on the fly from their transmitter instead of having to pull the car off the track to make such as imple adjustment.

Not only this but most radios offer MUCH finer resolution for this adjustment meaning you can make changes 1% at a time instead of at 25% at a time.

Reverse Amount:
This is pretty much exactly the same story as the brake amount. The adjustment is already there on most radios.

Punch:

In the mamba max this adjustment slows down throttle response.

Our racers have always wanted the fastest throttle response possible...so that's what we have given them.

Drag Brake:

The mamba has 5 settings in 10% incriments.

The GTB has 10 settings in either 3% or 5% increments depending on the version. This allows for much finer fine tuning of the drag brake instead of running into a situation where setting 2 is far too little and setting 3 is far too much :huh:

Start Power:

The Mamba has 3 setting values which dictate how much power the motor gets in start up.

The GTB has 5 setting values which can dictate how the motor "starts up." Again, these extra adjustments allow for much finer choice for feel.

Timing:

The mamba allows 3 different settings for motor timing.

On the GTB being as that our motors are sensored (and because we design, build, and test them to our exact specifications in our Irvine, CA headquarters) our timing is built in directly to the motor exactly how we want it... and because the motor timing is adjustable it is infinately adjustable within the minimum and maximum timing points that we have found to be optimum for our system.

Cut off Voltage:

The mamba allows you to select your lipo cut off voltage.

Again, since GTB was designed as a racing ESC and Lipo batteries were not and sill are not legal under sanctioned racing we decided to not include a function for this in an effort to create a smaller/lighter/simpler unit.

Brushed/Brushless:

Both ESCs allow for brushed and brushless mode operation.

In addition to the other adjustments mentioned above and below, the GTB also features a drive frequncy setting which allows the user to select one of 7 different drive frequencies for fine tuning the feel performance of their brushed motors.

Mamba Maxx does not offer drive frequency adjustment.

Dead Band:
This is the area that we allow to be adjusted to help smooth out initial throttle/neutral/brake signals to the ESC.

We offer 5 adjustments for this in 1% increments.

Mamba Max offers none.

Minimum Brake:

This is the value that we specify for the first amount of brake that the motor sees out of the dead band. While this is tied in closely with the Drag Brake setting on our ESC we have 10 different settings in 3-5% increments depending on the version of the ESC.

Mamba Max offers none.

People knock the GTB because it doesn't have USB interface, but the fact of the matter was that we considered it but opted to not included it for a number of reasons, 1.) of which being that the extra hardware/space needed would be frowned upon by the intended user and 2.) Our experience with the Pit Wizzard and computer interface told us that at the time of the GTB's initial design people just weren't looking for that kind of functionality.

...but times change and you never know what we might have coming right around the corner! :cool:

ElectricThunder
03-05-2007, 08:25 PM
So how much cooler does this spread spektrum compatible GTB run in comparison to a "regular" GTB? Is it a difference of a degree or two, or is it a drastic difference such as 10-15 (or even 20) degrees fahrenheit cooler?

(Also, if you could please check your PMs as soon as possible, I would greatly appreciate it.:))

Nomadio_Sales
03-05-2007, 09:27 PM
What no telem? 2.4Ghz is a two way com link so only setting the controller to work higher data rates is only part of the 2.4GHz picture.

So to be really up to 2.4Ghz speed here lets have a data out port so we can capture the data live on send it back out over 2.4Ghz oh yea..
AMP draw
Temp
Revs
Power curves all the good stuff the esc is already processing :D

scoob
03-05-2007, 09:30 PM
Steve Weiss-

Nice info. I think there is some bias out there right now becasue most people play and don't race. I do both but racing is more my thing.


I run a Mamba max 4600/5700 in my race truck. I used to run a Novak 6.5. The reason I switched was heat and thermal related in long races which the GTB wasn't really designed for. The guys I race with now have the sintered rotor setup and are getting much cooler temps. If they hold up when the temps hit 90 + this summer then I will be going back to Novak. After racing with sensorless I believe I was better off with sensored from a driving standpoint. I'm not a very good driver so I need smooth response. The 5700 and 6.5 motors feel like twins from a power standpoint but I feel like I had a little better throttle response and predictability with the Novak.

For bashing and such, the Mamba is awesome. You can have a system that never overheats and is capable of crazy power with higher voltage inputs. The ESC itself can handle so much power it's rediculous. I'm running one now in an E-savage with a 540 L can motor on 4s lipo and it never breaks a sweat. The price is great for what you get as well. It's loads of fun for play but for improving lap times, I'd rather run the Novak.

Just my unbiased opinion, I like them both.

tmhippo
03-22-2007, 02:54 PM
Where is the best (cheepest) place to buy a Spred Spectrum GTB?

NovakTwo
03-23-2007, 03:51 PM
Where is the best (cheepest) place to buy a Spred Spectrum GTB?

Novak will begin shipping the GTB Spread Spectrum versions next week.

Nomadio_Sales
03-23-2007, 03:59 PM
NovakTwo is there a way to get data out for telem? Nomadio is ready willing and able to make this the happen right now....

NovakTwo
03-23-2007, 04:20 PM
NovakTwo is there a way to get data out for telem? Nomadio is ready willing and able to make this the happen right now....

I sent you a PM.

ElectricThunder
03-23-2007, 04:21 PM
NovakTwo is there a way to get data out for telem? Nomadio is ready willing and able to make this the happen right now....
Are you talking real time data? That'd be useful for tuning the setup to the max. :eek:

Nomadio_Sales
03-24-2007, 02:44 PM
Real time and with data capture ;) Nomadio offered the industry telem output data and pin outs over a year ago.

InspGadgt
03-24-2007, 07:08 PM
Our experience with the Pit Wizzard and computer interface told us that at the time of the GTB's initial design people just weren't looking for that kind of functionality.

...but times change and you never know what we might have coming right around the corner! :cool:

Some people do...I still have 2 atoms and the computer interface for them and would much prefer some sort of interface then trying to remember what button sequence to push.

chilly4kc
04-19-2007, 08:35 PM
Just read this on Novak's wesbite:

The GTB and GTB Spread Spectrum ESCs now have built-in Li-Po Cut-Off Circuitry! This circuitry monitors the vehicle’s Lithium Polymer battery pack’s voltage, and prevents the batteries from going below the critical safety voltage level (6.25 volts).

For more details about the GTB, click here (http://www.teamnovak.com/products/esc/gtb/index.html)
For more details about the GTB Spread Spectrum, click here (http://www.teamnovak.com/products/esc/gtb_spread_spectrum/index.html)

Craps
04-20-2007, 08:39 AM
Sitting here waiting on my GTB Spread Spektrum to arrive via the little brown truck to test today and race tomorrow at the Farm in a 20 minute non-stop Pro Truck main!

Dagger Thrasher
04-20-2007, 12:09 PM
I gotta say, this new Spread Spectrum version of the GTB sounds pretty good! And if you and Nomadio can get together to provide realtime data output...just wow. That'd be awesome, as it would be if Nomadio did the same with Castle.

However...I don't think you really did a fair comparison of the Mamba. There might not be too much of a difference in programmability when doing it onboard the ESC, but there's no question that the Mamba is more flexible once you hook it up to a laptop (most settings adjustable in 1% increments).
And as for punch control...that's an excellent tuning aid. With a powerful motor, sometimes you want to tone it down a bit on looser surfaces.
I'm not trying to be awkward, just pointing that out.

Anyway, the new GTB looks to be an excellent update. :)

Craps
04-20-2007, 11:59 PM
WOW!!!!

You can feel a difference in how much smoother the throttle is with it and lap times dropped during practice today. Did not temp the ESC/motor, but we are getting little longer runtimes. We used it set in the #1 setting all day.

Forgot to even use the li-po cut off and ran the 8000 mah pack till it dumped. If you want the smoothest power band from brushless using a 2.4 ghz system, Novak has the best!

Race test tomorrow in the 20 minute non-stop main.

ElectricThunder
04-21-2007, 11:03 AM
WOW!!!!

You can feel a difference in how much smoother the throttle is with it and lap times dropped during practice today. Did not temp the ESC/motor, but we are getting little longer runtimes. We used it set in the #1 setting all day.

Forgot to even use the li-po cut off and ran the 8000 mah pack till it dumped. If you want the smoothest power band from brushless using a 2.4 ghz system, Novak has the best!

Race test tomorrow in the 20 minute non-stop main.
Can you get temperatures on the spread spectrum version and compare it to a "regular" version? That'd be interesting to see.

Craps
04-22-2007, 06:59 AM
No, but we raced for 20 minutes non-stop at the famous "The Farm" raceway in Charlotte, NC with both the regular and spread spektrum with no problems. I even took the cooling fan off of my GTB. You gear it right, it is not needed in a stadium truck.

By the way, Novak equipment took the top 3 spots at this race. More later this week in my special race report.

Key
04-23-2007, 07:30 PM
Just read this on Novak's wesbite:

The GTB and GTB Spread Spectrum ESCs now have built-in Li-Po Cut-Off Circuitry! This circuitry monitors the vehicle’s Lithium Polymer battery pack’s voltage, and prevents the batteries from going below the critical safety voltage level (6.25 volts).
[/URL]

What about customers like me who bought the GTB b4 that recent cell cut-off feature Novak realized was necessary?

When Castle Creations, Schultz, etc.. bring out any upgrades for their competition ESCs downloading the changes directly from the manufacturer's website onto the controller is something that is made available.

Key
04-23-2007, 07:33 PM
Just read this on Novak's wesbite:

this on Novak's wesbite:

The GTB and GTB Spread Spectrum ESCs now have built-in Li-Po Cut-Off Circuitry! This circuitry monitors the vehicle’s Lithium Polymer battery pack’s voltage, and prevents the batteries from going below the critical safety voltage level (6.25 volts).
[/URL]

What about customers like me who bought the GTB b4 that recent cell cut-off feature Novak thought was necessary?

When Castle Creations, Schultz, etc.. bring out any upgrades to their competition ESCs downloading the changes directly from the manufacturer's website onto the controller is something that is made available.

sim600
04-24-2007, 01:31 AM
Yeah, slightly offtopic from the Spread Spectrum GTB, but with the normal FM GTB, how do you tell if you are buying the new version with LiPo cutoff or the old version? Thanks.

Nomadio_Sales
04-24-2007, 01:38 AM
On the Nomadio React you can put a temp on the ESC and the Motor too bad this esc did not put a data out port so the 2.4GHz systems could just send back the telem to the TX.

NovakTwo
04-24-2007, 10:45 AM
The GTB lipo cut-off circuitry upgrade and the new GTB Spectrum Version require both a firmware and a hardware change from the original GTB.

Novak will offer a low-priced exchange fee for those who have recently purchased an earlier version GTB.

For those who own older GTBs, Novak will allow an exchange into a different version---4-Cell GTB, SpSp GTB, or a 6-Cell GTB with the lipo circuitry---for the standard rmf exchange price.

The exchange information eill be uploaded to the TeamNovak web site this week.

What about customers like me who bought the GTB b4 that recent cell cut-off feature Novak thought was necessary?

When Castle Creations, Schultz, etc.. bring out any upgrades to their competition ESCs downloading the changes directly from the manufacturer's website onto the controller is something that is made available.

CharlieS
04-24-2007, 05:21 PM
Also, I got out and did some "hands on" track testing this week with a Standard GTB vs a 2.4Ghz GTB. THe differences in temps under higher loads like 3.5 and 4.5 are very noticable. I'm not going to quote any temps at this stage, but its more then "just a few degrees" for sure.

ElectricThunder
04-24-2007, 05:33 PM
Also, I got out and did some "hands on" track testing this week with a Standard GTB vs a 2.4Ghz GTB. THe differences in temps under higher loads like 3.5 and 4.5 are very noticable. I'm not going to quote any temps at this stage, but its more then "just a few degrees" for sure.
Finally! A semi-quasi answer to my question! Thanks Charlie.:D

sim600
04-24-2007, 10:09 PM
Thanks Charlie. Sounds like I'm going to invest in a DSM unit before my next Novak purchase. There goes all my money. :D

NovakTwo
05-01-2007, 06:40 PM
The Novak GTB exchange program information that I mentioned in an earlier post has been posted to the TeamNovak website.

The enhancements to our regular, non-warrantee exchange program are explained here:

...Different Model Exchange Program (http://www.teamnovak.com/cs/index.html)

The new replacement chart with prices can be found here:

Service Replacement Options (http://www.teamnovak.com/cs/web_options/index.html)

Novak has added these NW service options to allow customers, whose racing needs may have changed, to easily exchange products---ESCs, BL Systems, and Brushless motors---for other items within the same categories.

Examples:

Return an original Novak GTB and exchange it for a Spectrum-optimized GTB, or for a 4-Cell GTB.

Return a SS4300 and exchange it for a Novak Velociti 6.5T brushless motor, or for a SS13.5T Pro Stock motor.

sim600
05-02-2007, 01:14 AM
NovakTwo and Novak reps,

I've had nothing but good experience with Novak products so far and am still enjoying my SS+ and SS5800. I'm looking forward to the new Spread Spektrum GTB because of the lower temps but I'm interested to find out how the higher switch rate results in lower operating temperatures. Is it something easy for us laymen to understand? Thanks.

CharlieS
05-02-2007, 05:42 PM
Basically, the faster the mosfets turn on and off, the less heating there is, so the more efficient the ESC operates. You get cooler temps because of less losses.

When it comes to ESCs and how they work, there usually isn't an easy way to explain it. :)

sim600
05-02-2007, 08:42 PM
Thanks Charlie. :)

NovakTwo
05-04-2007, 11:28 AM
NovakTwo and Novak reps,

I've had nothing but good experience with Novak products so far and am still enjoying my SS+ and SS5800. I'm looking forward to the new Spread Spektrum GTB because of the lower temps but I'm interested to find out how the higher switch rate results in lower operating temperatures. Is it something easy for us laymen to understand? Thanks.

Here is a more detailed explanation (re-posted from another forum):

Over the years, the Mosfets used in Novak's ESCs have steadily gotten better and now we have reached a point of diminishing returns as far as the Rds On of the Mosfet is concerned. The GTB uses Mosfets that have a Rds On of 1.2 milli ohm. The PCB and wires have much higher resistance than the Mosfets, so why does the ESC still get hot? That is because most of the heat is caused by the switching losses and not the Rds loss.

In an ideal situation, we would like to see zero switching rise and fall times. Fast rise and fall times cause large current spikes and produce lots of radio frequency interference. In a power supply or piece of industrial equipment, typically the manufacturer encloses the power section in a steel box and uses a large ferrite core to reduce the RFI noise. We don’t have that option!

In the GTB design we have had to slow the rise and fall time significantly so that it would work with ALL the radios out in the field (slowing the switching rate brings the noise floor down by 30-35 dbm). Compared to other high performance ESCs out in the field, the GTB has the fastest switching rate as we use 6 layer power PCBs with lots of ground plane and high frequency capacitors to de-couple noise.

Slowing down the switching rate causes more heating because the Mosfets are in the linear region of operation for longer periods and that accounts for most of the heating in the ESC. Also as you slow the switching rate, the pulse width driving the Mosfets starts to look like a trapezoidal wave form instead of a square wave and that causes the trigger control resolution to go down.

The last issue is that the dead time between the electronic commutation required goes up as we have to wait for one bank of Mosfet to turn off before we can turn on the next bank. In our Brushless ESCs we have six commutation steps per revolution, so any improvement in dead time reduction and switching efficiency can be significant.

The Spectrum optimized GTB uses a very fast Mosfet drive circuit switching speed (in the order of 1uS or less) and that will translate into significant improvement in efficiency under high loads and much smoother throttle response. We at Novak are committed to bringing the best possible racing Brushless system out to market and we are continually pushing the envelope of technology. Spread Spectrum allows us to improve the system performance without affecting the radio performance.

One last note on the fast switching ESC: it does not interfere with the radios outside of the car, so you will not be causing interference to the car next to yours whose user has the traditional crystal radio.

sim600
05-05-2007, 04:25 AM
Thanks NovakTwo. I can't say I understand half of it, but that's really because of my poor understanding of electronics. Anyway, I'm sure everyone appreciates the explanation. I have a lot of faith in the Novak brand, so I'm going DSM soon to take advantage of the new spread spectrum GTB.

sim600
05-18-2007, 03:06 AM
I've got another question, not really about the esc, but about sintered motors.

I've got the Super Sport Plus 5800 esc and motor combo and it feels very free spinning, so much so that I have to sometimes open up my spur cover on my truck and grab the spur before I can actually feel my ball diffs. I understand that the new novak motors with the sintered rotors have a "notchy" feel to it. What causes this notchiness? If I replaced my endbell with the big bearing one and put in a sintered rotor, would my motor have this notchy feel too? In an endurance race where I'm not touching the brakes, would the old free-wheeling motor style be more efficient? Just very curious. Thanks.

Oops, that was 3 questions. Sorry.

Craps
05-18-2007, 05:58 AM
I highly recommend using a glitch buster or a capacitor added to the r/x to keep the current draw from low turn motors from pulling voltage from the r/x letting it drop to where it goes to fail safe or glitches. This problem only comes in where the truck is furthest from the driver's stand and a full throttle was needed to pull the voltage down from the r/x.

scoob
05-18-2007, 07:59 AM
I've got another question, not really about the esc, but about sintered motors.

I've got the Super Sport Plus 5800 esc and motor combo and it feels very free spinning, so much so that I have to sometimes open up my spur cover on my truck and grab the spur before I can actually feel my ball diffs. I understand that the new novak motors with the sintered rotors have a "notchy" feel to it. What causes this notchiness? If I replaced my endbell with the big bearing one and put in a sintered rotor, would my motor have this notchy feel too? In an endurance race where I'm not touching the brakes, would the old free-wheeling motor style be more efficient? Just very curious. Thanks.

Oops, that was 3 questions. Sorry.

I just did this with my old 5800. The notchy feel is caused by a much stronger magnet as far as I can tell. Yes it will have more resistance . On mine the diff will go before the wheels if the diff isn't too tight, almost like a brushed motor.
I don't know about the efficiency question but for me, I use the drag brake with the free-wheeling motors and can probably turn it off with this for more efficiency because the motor now slows a little on it's own. Everyone who has upgraded to sintered has said it helps things run cooler, so I don't think it could be less efficient regardless.

CharlieS
05-18-2007, 02:24 PM
The Sintered Rotor is stronger, so there is a stronger magnetic feel. Often you can run much less drag brake with a Sintered Arm because of this. The sintered rotor being stronger also makes the motor more efficient, so it uses less current to make the same power.

sim600
07-30-2007, 11:32 PM
Charlie,
Congratulations on the good run at the Worlds Fastest RC Car Challenge II.

CharlieS
07-31-2007, 04:11 PM
Thanks, we had a great time.

John from HPI had his Sedan up past 85 with a GTB/3.5R setup. It was geared very very tall. :)