Analog servos
11-05-2014, 04:59 PM
#28
if your digital servos can draw 5A you have big issues! 40A total!! The Rx would blow to pieces...
4.8v batteries are only at 4.8v when they are completely flat, they charge to 6v and operate happily around 5.6-5.7v. It's why JR '4.8v' servos are happy at 5.8-5.9v, it's the voltage they were designed to work at!!
its how the servo motor is powered/controlled that makes the difference between digital and analogue servos. Manufacturers have different ways of doing this in both types, some cope, some don't.
4.8v batteries are only at 4.8v when they are completely flat, they charge to 6v and operate happily around 5.6-5.7v. It's why JR '4.8v' servos are happy at 5.8-5.9v, it's the voltage they were designed to work at!!
its how the servo motor is powered/controlled that makes the difference between digital and analogue servos. Manufacturers have different ways of doing this in both types, some cope, some don't.
Most 9+ channel Spectrum Rxer Manuals tell you flat out not to use 4.8 V batteries. Wonder why? Also, many articles are published on this topic.
Bottom line: Analog servos operate sequentially and Digitals can operate simultaneously. When using digital servos the current used simultaneously adds up and, ... some of these servos can momentarily draw up to 5 amps. You may not see that level on your current meter because of the meter's refresh cycle time is too slow. But, it shows up on a good scope with a lock. Again several articles on this topic are out there and easy to get hold of.
11-05-2014, 06:14 PM
#29
Been using servo's like 2721's, 4131's, 8231's, 3421's etc on 2.4 in mutliple jets since switching to 2.4 nearly 9 years ago and never had a problem. Only issue I had with 2.4 and any component was with an amplified Y harness in my kingcat when I upgraded the stab servo's to 8611's. Got rid of the Y harness and no issues.
11-05-2014, 06:47 PM
#30
My Feedback: (2)
Off topic, but someone mentioned 225MGs. I had three of them fail. One failure resulted in a bad crash. And I am not alone - check the online reviews. That was some time ago and maybe Hitec has fixed the problem by now. But to be completely safe, I recommend you take them out of your twin and smash them with a hammer so that no one else ever uses them.
11-05-2014, 06:59 PM
#32
Off topic, but someone mentioned 225MGs. I had three of them fail. One failure resulted in a bad crash. And I am not alone - check the online reviews. That was some time ago and maybe Hitec has fixed the problem by now. But to be completely safe, I recommend you take them out of your twin and smash them with a hammer so that no one else ever uses them.
11-06-2014, 11:12 AM
#34
Join Date: Dec 2005
Location: Shrewsbury, MA
Posts: 391
Likes: 0
Received 0 Likes
on
0 Posts
I have many airplanes that use Spektrum receivers and use both Hitec and JR analog servos powered by 6V NiMh batteries. I have not witnessed any issues with servos and receivers not playing nice with each other. A couple of my planes have a mix of both JR and Hitec servos installed.
11-06-2014, 03:06 PM
#35
Myth, I've had analog servos that center better than new out of the box digitals. some do and some don't, in my planes i can't show you where a digital performs over an analog, maybe if they are operating at there extreme limits something might show up but i dont do that all mine are the size recomended or past that.
