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When are digital servos justified?

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When are digital servos justified?

Old 01-03-2011, 09:10 AM
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orbsah
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Default When are digital servos justified?

Hi all - I'm considering a Futaba 7C for my next radio and wondering if the standard S3004 servos are good enough or I should spend the extra $30 for S3152 digitals. I realize the digital servos will draw more current, have more torque, etc. I typically fly 60'ish size sport/pattern planes. My current project (where this system is intended initially) is a TF DC-3 (82" span).

To summarize the question, is there a general guideline for when to consider digital servos? Thanks.
Old 01-03-2011, 09:26 AM
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BarracudaHockey
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Default RE: When are digital servos justified?

Where high torque and high precision are required.

Helicopter, 3D and very aerobatic planes benefit from the speed and precision.

Trainers and T28's not so much.

As an aside, there are some very good analog servos and some cheap crappy digital servos so the fact that it's analog or digital may not tell you the whole story.

For a DC-3 (assuming we are talking about the prop driven air liner) any servo that meets the torque spec's would be fine, you wouldn't see much difference with digital servos. With a Yak or Funtana or something it would be like night and day
Old 01-03-2011, 11:07 AM
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Default RE: When are digital servos justified?

I'm with Andy on this. For your style of flying, you'll never notice a difference.
Old 01-03-2011, 12:25 PM
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summerwind
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Default RE: When are digital servos justified?

i'm with both guys above, but for the minor increase in cost, go for the digitals. even if you don't notice the difference, the extra holding power is worth it and will make using them in something bigger a lesser issue later on.
Old 01-03-2011, 08:14 PM
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Default RE: When are digital servos justified?

Stick with the 3004. Unless you need digital servos, the extra battery drain is not worth it. The 3004 servo's are a great everyday servo. Good Luck, Dave
Old 01-04-2011, 01:54 AM
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Default RE: When are digital servos justified?

As stated above for digital/analog......what you need to be worried about is torque. You need a servo that can handle the DC-3's requirements.....The instructions should tell you the torque specs recommended
Old 01-06-2011, 05:21 AM
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Default RE: When are digital servos justified?

For my slow planes I use analog, for fast planes like expensive warbirds,3D stunt or Pattern I use digitals. Digitals are power hungry so it's good to use a 1000mAh or higher if you want to get 4 flights in or more.

I agree with everyone here on what they have written.


Pete
Old 01-07-2011, 05:55 AM
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Hewey19
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Default RE: When are digital servos justified?

Don't buy any servos and upgrade to an 8FG.
Old 01-07-2011, 10:02 AM
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Gray Beard
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Default RE: When are digital servos justified?

I tell my students to always buy the best they can afford. Servos and gear will be with you for a long time so if you buy the best you can afford now your gear will transfer to bigger and better planes in the future. The few extra bucks for the digitals at this point is a pretty good idea even if your plane doesn't require them. Someting you don't need today may be something you need in the future, look ahead.
Old 01-07-2011, 10:32 AM
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Luchnia
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Default RE: When are digital servos justified?


ORIGINAL: Gray Beard

I tell my students to always buy the best they can afford. Servos and gear will be with you for a long time so if you buy the best you can afford now your gear will transfer to bigger and better planes in the future. The few extra bucks for the digitals at this point is a pretty good idea even if your plane doesn't require them. Someting you don't need today may be something you need in the future, look ahead.
Totally agree and the digitals work really nice. I can tell a big difference on my planes when running digs with 6v...real crisp [8D]
Old 01-08-2011, 07:29 AM
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Daryl_y
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Default RE: When are digital servos justified?

I would think that if your next project 82" wingspan DC 3 it would require gaint scale servo's with more torque than either the 3004,3152 we are talking about here. When I built my Sig King Kobra I installed Futaba 9001 (coreless aircraft) servos on rudder, elev and ailerons. While still being an analog servo it is comparable in torque and precession to a std size digital servo and is a good upgrade from the std 3004.
Old 01-08-2011, 09:56 AM
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summerwind
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Default RE: When are digital servos justified?


ORIGINAL: Gray Beard

I tell my students to always buy the best they can afford. Servos and gear will be with you for a long time so if you buy the best you can afford now your gear will transfer to bigger and better planes in the future. The few extra bucks for the digitals at this point is a pretty good idea even if your plane doesn't require them. Someting you don't need today may be something you need in the future, look ahead.

excellent advice.......also the 3152's will be more than enough power to handle your DC3
Old 12-28-2011, 01:31 PM
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Default RE: When are digital servos justified?

Alot of good advice/pros and cons. If you have a digital radio and a larger heavier plane with large control surfaces then digitals are a good choice. Size of control surface dictates torque requirements, most instruction manuals will tell you that info. digitals draw more energy because they are always in a holding mode and do not creap like analog servos do. On 60 and40 size planes it's hard to justify digitals because analog works just fine. On the other hand if you have a bat out of hell 3 D'er you may want to reconsider the digitals. Analog is usually the choice for throttle in most cases. Leroy
Old 12-28-2011, 02:59 PM
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Roary m
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Default RE: When are digital servos justified?

3004 is a ball bearing servo; use a 5 cell pack and they will behave like more expensive ones.

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