RE: FM or PCM ?
 

They need to make transmitters with lock/key encryption...and channel searching like corless phones....would kill the whole problem at once...

RE: FM or PCM ?
 

I'm told the prototypes for this technology are complete. 2Ghz....[8D]

RE: FM or PCM ?
 

this is looking more like the beginning of an ad for the new Specktrum DSM technology from Horizon Hobby. I can see the storyboard now:

RCU Poster: FM or PCM?
RCU Replies: [Both are okay... but there must be something better]
RCU Poster: They need to make transmitters with lock/key encryption...and channel searching like cordless phones....would kill the whole problem at once...
RCU Poster: I'm told the prototypes for this technology are complete. 2Ghz....
RCU Poster: This is looking more like the beginning of an ad for the new Specktrum DSM technology from Horizon Hobby
RCU Poster: That's awesome, dude... where can I get one of these "No Glitches. No Crystals. No Pins. No Interference. Pure Digital Control" radios?
RCU Poster: While it's not available for aircraft at this time, I hear that it is being developed and will likely be introduced to the market in due time. You can, however, keep up with the developments of this new and exciting product by visiting www.horizonhobby.com from time to time. The picture attached was accidentally discovered while aimlessly meandering the web.

:eek:

RE: FM or PCM ?
 

Call me skeptical, but I have done plenty enough 2.4ghz stuff with wifi to know that it is a very crowded band that does not always work. If I have to pick between channel management on a clear band, and trusting some frequency hopping protocol on a crowded band I'll live with the frequency management, at least for now. While these new digital frequency hopping protocols are immune to interference in the sense that they won't get instructions from another transmission, they are not immune to interference that breaks down the protocol link. While frequency hoping and spread spectrum tries to get around this problem, it still has problems on a crowded band. According to the information at http://www.horizonhobby.com/Shop/ByC...ProdID=SPM1001 the transmitter looks for a free channel before transmitting. While that would work fine inside the 72mhz band, I have my doubts about it working in a band that also has wifi, bluetooth, cordless phones, video transmitters, etc. Also keep in mind that these devices may not be so polite about steeling your channel.

I'm all for digital radios and automated channel management, just not on the 2.4ghz band.

Edit: spell chucker didn't work for me.... :(

RE: FM or PCM ?
 

A well-placed typo :)

RE: FM or PCM ?
 

Just to add a data point to the thread, I've noticed that my planes (including exactly the same plane and transmitter but switching from FM to PCM receiver and switching modes on the transmitter) will range check about twice as far with PCM. When I range check I do move the surfaces smoothly up and down so I can tell that the PCM isn't holding intermittently.

Because of this, I fly PCM on anything expensive or that seems likely to have interference problems because of antenna setup. No idea if it's ever solved a problem that I would have had with FM or not.