R/C Tech Forums - View Single Post - DSM vs. FM - can you feel 5 milliseconds?
Old 07-16-2006, 07:00 AM
  #31  
cvt01
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Does anybody really understand how the total latency of the transmitter adds up?

Here is what I think, lets discuss it:
total latency= radio latency + module latency

I think BOTH FM and DSM modules has latency. The radio's latency is constant independent from what type of module we are using.

We discussed this with a couple of guys and here is what I think about the latency on my 3PK:
- the radio has an inside latency of ~3ms

Futaba modules
- the PCM module's latency is ~30ms
- FM module's latency is ~18ms
- HRS module's latency is 7.8ms

Spektrum Modules
- Spektrum module's 5.6ms
- Spektrum Pro module: 3ms
- Spektrum HRS: 2ms

So the TOTAL latency ranking will look like this:
PCM - ~33msec
FM - ~21msec
HRS - 10.8 msec
Spektrum - 8.6msec
Spektrum Pro - 6.5msec
Spektrum HRS - 6msec

I'm not sure about the 3PK 3ms internal latency it may be much lower than this.

Is this make any sense or I'm way off???
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