mvigod

Couple questions about digital servos...I've never used them or considered using them as I've used the standard analog type for so long I just got used to them. Well today at the field a few interesting questions came up and to be honest I never really read much about them and made a few assumptions which may in fact be wrong. Oddly enough nobody at the field knew the answers to these questions so I'm coming here to find out and let 'em know!

First - I always assumed a digital servos was only for use with a digital tx and rx. So is this in fact the case or can a digital servos be used with ANY type of rx? If used with a standard FM receiver (if possible) is there any loss in the advantages of a digital servos versus using them with a digital rx?

Second - If the motor and gear trains are the same in a digital as a standard servo what is the reason that they have more precision, less dead-band, more speed and more holding power?

can773

My Feedback: (1)

Here is a pdf that should help clear some stuff up

http://www.futaba-rc.com/servos/digitalservos.pdf

Geistware

My Feedback: (16)

The link above will give you the info you seek. Just remember that the digitals have higher update rates as well as if a digital actual position is 1/1024 off from the commanded position, you can tell it to put out as much power as you want to get back to its correct location. Because of this programing, digitals are stiffer than analog which must build up error to get enough signal to correct itself.

mvigod

ok..that covers most of question 2...what about question 1?

thanks

Forgues Research

My Feedback: (7)

Speaking of digital servos, I am looking for the digital servo amplifier only. I want to modify a special servo to digital for a special application, would anyone know where I can find some, or even bad geard servos with good amplifiers
Thanks for any response.

amcross

My Feedback: (2)

Hi, Marc! Absolutely, digital servos can be used in any installation. They don't care about what your receiver is any more than an analog. You do not lose anything, no, performance wise. You DO, however, really see the big gain in digital's frame rates when you go to high end PCM installations with the 9Z, as it has an accelerated frame rate to utilize this advantage.

mvigod

Ann Marie,

Thanks...couple small follow ups...on a regular radio that also does PCM do they also provide the same high rates as the 9Z or does the 9Z offer higher PCM rates than typical PCM Tx's?

Would a "regular" PCM cabable Tx (not 9Z) provide the same equivalent advantages as a regular FM tx and rx would with the digital servos or more?

amcross

My Feedback: (2)

Hi Marc!
The 9Z WC2 is the only radio I know of to offer this accelerated frame rate response.

Otherwise, yes, response would be similar FM vs PCM.