RiffRaff

My Feedback: (16)

I have recently been upgrading (well adding to) my radio equipment and decided to give the PCM/Digital side of things a whirl. I know very little about this PCM/Digital tech.

I just received my new Futaba 7CHP and got to wondering about these digital servos. I know the 3151's that came with the radio are the low end of digital servos but I put a S9253 in the tail and I must say impressive!

I am fully aware of the PPM vs PCM debates which is part of the reason I decided I needed to take the plunge and try PCM and decide for my self what, if anything, is really gained.

My question is this:

Do you need a PCM Rx to use digital servos? I understand that this Rx with PCM 1024 has higher resolution than the older PPM systems, correct? The real question is if I ditch the 3151's for something better can I use them in one of my older PPM systems? What do I loose by doing so? Anything?

A little clueless...?

Riff

RiffRaff

My Feedback: (16)

Ah, I just notice that the 7CH (PPM) vesion ships with the S3151's as well, so I am assuming that means I can use digital servo's on standard PPM RX's?

Silent-AV8R

Digital servos do not require PCM or even regular old FM/PPM. AM will work fine. The sevros don't care how the signal gets to the RX.

dirtybird

My Feedback: (5)

PCM has a fixed 1024 steps for the range of rotation of the servo. PPM theoretically has an infinite number of steps for the same range. Practically the resolution will be determined by the servo used for both PCM or PPM.

RiffRaff

My Feedback: (16)

So essentially there is no difference between a PPM vs PCM RX in terms of the sevo capability?

Well, other that the fact that PCM is a discrete 1024 digital steps versus the thoretically infinite resolution of analog PPM?

Thanks all!

Riff

mr_matt

My Feedback: (10)

Well to throw you off even more, the digital servo samples the input signal from the rx, so even if the signal from the PPM rx is "infinite" then the digital servo will quantize it, probabaly back to 1024 steps anyway,

DadsToysBG

My Feedback: (35)

Some of the new digs have a 5800 step whether you use PCM or PPM. Bytheway PPM on stock are 512 coreless with PCM are 1024. Dennis

lownslo

moved.

dirtybird

My Feedback: (5)

I sure would like to know what you are trying to say here. Whats a dig? Whats a 512 coreless? Coreless is a type of motor, and has nothing to with PCM or PPM.