ppm and pcm recievers

[big kev]

can any one tell me the differances and advantages of pcm recievers over ppm used to race 1 5th cars and remember using pcm but cant remember the real advantages will be getting a raptor 50 soon so would like to know which one to use

[Disc]

PCM has the failsafe and cuts out unwanted RF noise better.

PPM is more likly to get RF noise (glitchs)

Our Club requires PPM Receivers on helicopters to have a throttle cut on them just in case.

PCM Fail safe must be set as well.

I'd say go PCM just because it doesnt suffer from glitchs as much (RF noise as much)

Nothing worse than a glitch when learning!

[jimbob]

Basically, PCM has two advantages:
1. They have failsafes
2. Because of the transmission system used (digital) they have a better ability to reject interferance.

The down side of that is that you dont know you are getting interferance until much later, and then you get locked out by the failsafe.

[rambo]

I prefer PPM with a failsafe added on.....

You still get the minor glitches which tell you there is something wrong, and if things get too bad, the failsafe will cut in.

[Butuz]

I always wondered whether masking out the glitches was a good idea. This spectrum stuff has me asking the same questions - what if you get glitches that cant be corrected? You wouldnt know about it till you hit the deck would you?

Butuz

[robgt]

I'll stick with PCM
The pro's use it by choice for a reason...

Cheers,
Rob

[3dbasher]

I'll stick with PCM
The pro's use it by choice for a reason...

Cheers,
Rob

agreed yet again

[Ade_Law]

pcm will warn you that something is up but giving you short periods of "hold" where the controls stay in their last position. most of the time it will come back from that state. If you ignore that warning you could end up with a full failsafe condition which will result in a crash.

PPM does give you more warning in terms of uncontroled glitches sending the model of in any direction, this could be at the ground. Also the level at which PCM locks out is beyond what a PPM reciever will work at so PCM works for longer in bad circumstances.

i am yet to see a dx7 lock out. its certainly going to be interesting how much data it needs to come back from a fail safe and if you get any warning of it happening.

Ade

[showtime]

with the Spektrum system we use in the cars you do get very occasional lockouts (caused by static we think) & the only way to get the RX back online is turn it off & on again

they just stop at the position they were at! which is unfortunately usually full throttle, they just ignore any failsafe settings

hopefully the aero versions wont act the same

[jimbob]

One day, the link will be bi-directional, and the model will tell the pilot that its getting glitches, or the battery is failing, etc etc ...

Now THAT will be worth paying for!

[Smoothound]

My car system virtually has that now but not quite as clever as you'd like but it sends temp, voltage, rpm back to a screen on my Tx

[jimbob]

Its only a matter of time....