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Old 03-25-2007, 02:14 PM   #31
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Originally Posted by Rapid Roy
There have been a number of people who have had their digital servos die when used for throttle. The problem is when applying it brake. If you brake hard and hold them, the servo has to work really hard to hold the position. The digital servos check there position much more rapidly then analog and it applies power each time. This happens enough to burn up the servo. Some people never have this problem. I think this can be explained by different driving styles, brake linkage setups and track size.
Just a tip : people should set EPA ( End Point Adjustment ) for full throttle position AND full brake position with the engine in place. Look at the carburator openings to see maximum throttle position and lock it there. Ditto with brake. When the tires are feeling locked .... then lock it there.
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Old 01-01-2008, 01:16 AM   #32
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with the regular servos the the car does not turn fast for fast stearing is the only way belive me i pay more than 5 servos too lern it!!!!!!! here in greece we are saing you get everything you pays
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Old 01-01-2008, 04:33 AM   #33
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hey guys
will Airtronics 361 work on a HRS system??

i just got my 361 servo and didnt realise it was an analog, its working on HRS. but will it cause it to stop working if i continue??

thanks
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Old 01-01-2008, 07:01 AM   #34
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Originally Posted by twiggy View Post
i always use digital in 1/8th onroad and 1/10th tourer.
not only do they have more holding power but they also hold their center better.
as far as runtime goes, i figured im not going to be racing any longer than 30 minutes at a time. my 1200mah lasts over 30 minutes powering 2 digital servos, a personal transponder and a KO reciever with hrs.

i use ace digital servos and have not had one fail on me yet in over 1.5 years of constantly using it!
Totally agree, I could not have expressed it any better, same experience here ...
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Old 01-01-2008, 08:22 AM   #35
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Originally Posted by Serpentd View Post
You guys might be right. I'm compairing the JR9000S (A $120 USD) servo which is digital. When you move it with your hands, yes it is smoother. But this is due to it being coreless. The coreless analog feels the same way.
The analog that I use is the Airtronics 94357 and 358...the 359 and 360. These are $120-150 USD. This is what I am compairing to. If you move them by hand, no they don't have that smooth feel. But as far as on the track where it matters, I don't notice the differnce in smoothnss at all. They all feel the same to me. I have been using the Airtronics for over 8 years, and just recently tried the JR, which is a very nice servo as well. But still no difference at all. Other then the JR sucks more power. They happen to be the same price as the 357and 359 with the exact same specs. .06 sec/60 degrees and 125 in/oz of torque the 358 and 360 is .08 seconds with 200 in/oz of torque. I still prefer the analog and have NEVER had a centering problem once in the 8 years I have used them. I use them in 1/8 scale on road, so centering is very important, as is with all cars for that matter. The difference between the 357,358 to the 359,360 is the higher numbers have aluminum heat sinks is all.

Like I said earlier, the main difference is suppose to be the HOLDING torque. Now if you are compairing 50 dollar analog to 100 dollar digital, that's not a very wise comparison. Get my drift. Good luck guys. Maybe goto a radio Manufacturers site and see what they have to say about digital. Just be careful as marketing can try and fool you a bit.
Digital servos takes advantage of the high response system of the new controllers which have HRS system
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Old 01-01-2008, 08:40 AM   #36
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Quote:
Originally Posted by Rapid Roy View Post
There have been a number of people who have had their digital servos die when used for throttle. The problem is when applying it brake. If you brake hard and hold them, the servo has to work really hard to hold the position. The digital servos check there position much more rapidly then analog and it applies power each time. This happens enough to burn up the servo. Some people never have this problem. I think this can be explained by different driving styles, brake linkage setups and track size.

Set maximum brake limit position through your EPA. ( Brake limit position = maximum holding position at full braking power without locking rear wheels ). That's how you won't burn a digital servo.
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Old 01-01-2008, 09:39 AM   #37
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Originally Posted by emulson View Post
hey guys
will Airtronics 361 work on a HRS system??

i just got my 361 servo and didnt realise it was an analog, its working on HRS. but will it cause it to stop working if i continue??

thanks
can anyone help??
thanks
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Old 01-04-2008, 05:12 AM   #38
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Originally Posted by emulson View Post
hey guys
will Airtronics 361 work on a HRS system??

i just got my 361 servo and didnt realise it was an analog, its working on HRS. but will it cause it to stop working if i continue??

thanks
cnu ka?
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Old 01-05-2008, 06:56 AM   #39
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Many of the points made here are very true. I have found that you want to avoid ABS for the long life of your servo. You also want to be careful when setting your fail safe. It would be better to set it at netural as oppose to forward brake.

I lost two digital servos because I did not turn off the receiver in time when the FS was activated. The servo locked up.

Setting your EPA must be done with everything in place. You need to also remember to check this when you switch engines during qualifying. You want to set the throttle just as you see the carb at WOT as mentioned by Artificial-I. As for brake, you want to avoid having your wheels lock up for best results.

My personal preference of servo so far is the S9550. These are still going strong after a year of racing. I tried the KO 2413ICS last few race days and found it is not as fluid as the futaba at all. I changed back to the Futaba's this week. I opened up one of the 2413's last night while working on my electic car and figured out the reason why is because, the teeth in the KO's are alot more course than the Futaba's. The gears mesh at slightly different angles as well.

I then decided to take some of the guts from an old S9550 and drop it into the KO and it now works alot more smoother.

I understand the point made about using a standard servo for throttle, but if you want to use Futaba's HRS feature, it is my understanding that all servos must be digital?
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Old 01-05-2008, 03:23 PM   #40
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Originally Posted by Artificial-I View Post
If you have a digital on throttle. Just dont use the ABS function. Another is the Futaba S9450 has known problems for being on throttle. So if you get that servo , be sure to not use it for throttle. S9451 should be fine though.

As for other servos you might run into some problem with other brands on throttle , but most likely from abs or improperly setup setup linkage. Basically you dont want the servo pulling farther than it can mechanically brake or throttle. More times than 1 ive seen users giving it throttle on the radio and their chassis bends and the motor moves. You gotta set it to move the full range it can go and stop it right at that point to where the servo doesnt have a loaded sound when going full gas or brake. AKA setting your end points.
I totally agree about don't use a digital on the throttle when using ABS. I have found that 1) I can't tell ANY difference between an analog and a digital when driving the car. 2) digital servos drain the batteries much more quickly than analog. 3) Using a digital and ABS on throttle = very short servo life!.

I personally like the KOPROP servos the best because they have very low internal resistance when there is no power going to them. This is important because I use a rubber band as a throttle return spring and the KO servos with their low internal resistance will close quickly in the event that my battery dies or a power wire breaks. The rubber band trippled and wrapped around the carb neck and the ball on the throttle linkage has saved many a car when there was a power failure. Cheap insurance!

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Old 01-05-2008, 03:59 PM   #41
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With ABS I have no feeling in the brake, I did try it but could not get used to it.
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Old 01-05-2008, 05:08 PM   #42
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Do you guys use the rubber isolators and eyelets supplied with the servo?? Thanks
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Old 01-05-2008, 05:19 PM   #43
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Originally Posted by insanewulf View Post
Do you guys use the rubber isolators and eyelets supplied with the servo?? Thanks

Personally I do not, but know that some recommend it to avoid breaking the servo support. I have never had this problem even after a crash.

It might be a good practice to use it.
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Old 01-05-2008, 07:15 PM   #44
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Originally Posted by insanewulf View Post
Do you guys use the rubber isolators and eyelets supplied with the servo?? Thanks
I think the rubber isolator is more like to reduce vibration from the car, which is always a problem in early generation of digital servo.
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Old 01-05-2008, 08:43 PM   #45
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Originally Posted by insanewulf View Post
Do you guys use the rubber isolators and eyelets supplied with the servo?? Thanks
No with steering, yes w/ throttle.

I want exact, consistent centering on the steering and no give except my servo saver on the chassis. I don't mind if the throttle gives a touch, plus the throttle is generally screwed (sandwiched) directly to the upper deck and could use some flex.

The steering throttle has some give on impact because it is screwed to a plastic mount which is then screwed to the upper deck (plus the servo saver protection).
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