Please, can anybody tell me why a programmable servo is better than other? Which is the advantage in pattern? Is not the same than programming the Tx?

Yes, it is the same programing as the radio, the only thing you can program on a Hitec servo you cannot do on the radio is the Deadband With, JR and Futaba servo are non programmable because they come at the peak of performance and precision, Hitecs or Multiplex needs to be programed because they come with a lower deadband with precision so they don't fight each other when you have multiple servos on the same surface.

Does that mean I shouldn't buy Hitec servos if I'm not going to program them?

No, not really. Hitec's just give you the option. Also helps for setting up servos if you are limited on what your radio can do. I personally don't think Hitec's servos touch, Futaba, JR, or Airtronics, others will argue, but I think they are a good option price wise, but not quite the quality, especially for pattern as I dont think they are as precise as the other 3.

Arch

Yeap!! still speaking about servo programming but: what can I program on a servo and what for?

As I said before, you can program the same thing you can program in your radio, the difference is the center precision, and if some one is going to use Hitecs for pattern they MUST be reprogrammed for deadband =1 they com set at 2 out of 16, if that is not done, it will be a useless servo for pattern as the centering precision will be minimal.

Of course, all this comes from using JR premium and Hitec servos, my comparisons come from experience,but if somebody has only flown Hitecs, that person will not understand what most pilots mean when referring to the servo precision.

Eh amigo pereira, parece que no te gustan los servos hitec... je!! no doubt they're not the best, but give them some credit!
So you can program the servo independently of the Tx?
Un saludo...

Yes, you can set your endpoints and such independently of the TX.

Arch

Hola Guille,

I have more than 20 Hitec digitals, I love the Hitec servos, but not for pattern, that's the only thing, I use Hitec for my scale airplanes and Funfly, but for precision flying either F3A or my QQ 102" Yak I only use JR, the difference is huge.

Saludos

What do you program a servo with? (other than the radio).

Edit: Nevermind, found it. For the price of Hitec and the programmer and the hassle of going through it all, you might as well just get some better servos (in my opinion).

Boy, am I having some growing pains!!! I recently stock piled some DS821's thinking they would be fine for a while as they seem to be working the Venus, now I need at least two $99 130oz servos for my rudder and single-servo elevator on a 120 size hybrid?? 6 months ago I didn't even know how to fly a plane and went with 'upgraded' ball bearing standard servos on my trainer[X(]

Any chance of a sponsored prospect? I wouldn't be lying if I said I've entered two pattern meets in my first season flying and took home a third-place and a first-place plaque!

Better servos and a radio that will allow you to adjust endpoints is a better strategy. OK, as for the DS821's you already have, you can certainly use one each on ailerons. You could still use some Hitec servo for elevator / rudder to save money and just skip the programmer part. You lose some accuracy, but they're OK if you don't mind that.

I don't know what 120 sized hybrid you are putting together, but let's assume it's something close to a full size 2M ship. You definitely do want to get into the 90 to 100 oz-in range for elevator and 120 oz-in or more for rudder. Keep in mind that JR servos are quite happy running at up to about 6.5V, so if you use a good regulator and a 2 cell LiPo pack, you can get that type of output and get more speed and power out of your servos. Since the DS821 is rated at 88 oz-in at 6V, you could get it in to the 90 oz-in range at 6.2 to 6.5V, depending on how you set up a regulator for it. So now you just need to go find yourself an affordable rudder servo.

Go to tech-aero.net and look at my regulators. If you like what you see there, email me using me the support email link and we'll get down to business on how to set up a good system to get your existing servos humming along better, and maybe I can help you out with a used DS8411SA at a good price too.