|
|
|
|
|
|
||
|
|
Quote:
|
|
|
||
|
|
|
|
|
When using the iPhone to fly the ARdrone, Parrots recommends you put the phone in airplane mode.
You can do the same when using the STi device. |
|
Latest blog entry: Get Help by posting your SPM File
|
|
|
|
||
|
Joined Mar 2009
231 Posts
|
Quote:
The lower picture was taken on the 104th floor at Sears/ Willis tower plugged into the South antenna of a TV ENG receive antenna. This is the same screen scan setup.. Notice how much lower the noise floor is in one of the noisiest areas in the country off this antenna, but look at the junk operating in the same space as my DX8. Whatever it is, it's loud enough that we cannot run 2GHz TV links with 10W transmitters into +20db directional antennas on both ends. This interference, including that from us RC folks was mentioned during a meeting with the National Association of Broadcasters recently while discussing what services are being shared in this band. I captured screen shots at 2.4GHz at Sears & Hancock towers in Chicago, and 3 mtn.tops in So. Cal, and the results are essentially the same, although Chicago was considerably more congested being in the center of town. The good news is that 2.4GHz drops off fairly fast, and data links are usually on highly directional antennas. Thank goodness DSM(X) is as robust as it is, because there is competition out there for this space.At least most of the bad stuff is in the metro areas, but in my book cell activity is way down the list of worries. DX8 & TM1000 SEARS Tower South Antenna/ LNA Off |
|
|
||
|
|
|
|
Central California
Joined Dec 2006
1,892 Posts
|
Jeff you are opening a huge can of worms.Im no RF expert by any means and I let my ham license kind of expire some years ago but Im trying to get back up to speed a little more.One thing I learned/relearned is I cant use analog logic in a digital world.The way we use RF is completely different than in the past.At least from what I was used to 20 years ago.I have a couple spectrum analyzers and just because a band is being used doesnt mean it cant be shared.Ive found some pretty harsh environments and the system still works.Ive seen places where an analyzer will show reasonable RF all across the 2.4 band.Some may call it "saturated". All frequencies are being used.There is still room to get an RC system to connect and be usable.Even DSM2 which many claim to be obsolete in the ever harsher 2.4 environment we all try to share.True enough there are situations where it could be at a distinct disadvantage but IMO they are still very rare.Alot of the claims of inherent problems and conflicts IMO are based on misconceptions of how the bandwidth is being used especially the amount of time it is used(when and where).
Huge can of worms. As long as all the users stay within the laws/rules/guidelines theres still plenty of room for everyone to play well together.There is potential for conflicts but for the most part its not a "sky is falling" scenario. |
|
|
|
|
||
|
Belgium
Joined Aug 2008
27 Posts
|
Quote:
Finally updated (from 2.3beta) and glad so far! My Carbon Cubs basic telemetry is working ;-) Thanks for helping. Best regards, Tom. |
|
|
||
|
|
|||
|
Central California
Joined Dec 2006
1,892 Posts
|
Quote:
Quote:
http://www.helifreak.com/showthread.php?t=354008 |
||
|
|||
|
|
|
|
Joined Mar 2009
231 Posts
|
I'm not opening it, I'm just pointing out what I see and how congested this band can be in the right area. It's still WAY WAY better that a single carrier device that can get completely creamed, THIS at least system has redundancy.
With the TV guys, the shoe is also on the other foot. We install ENG receive sites at the top of buildings, mtns., and local hills, some of those exactly where the glider guys fly. So not only is it possible that the pilots radio can get into the receiver, but also the glider flying by the antenna at 100mph with it's telemetry. We don't have the luxury of frequency hoppers, ours is a 6MHz carrier, and if a hole is punched anywhere in that carrier, away goes pix. BTW, the point of those pix was to make the case that the TV guys cannot co-exist on 2.4GHz (ENG Ch.8) with any of those data services, and are now, at least in the Chicago mkt, working to move elsewhere in the band. That's a good thing for everyone. Back to the thread.. PS: I have also heard rumors of excessive holds at Apollo Field in So. Cal, so I might take the analyzer out and let it run for the afternoon some day. |
|
|
|
|
||
|
Joined Sep 2012
428 Posts
|
Quote:
|
|
|
||
|
| Thread Tools | |
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Question Receivers that work with Spektrum Radios that are not made by Spektrum | BD Flyer | Radios | 29 | Sep 26, 2010 04:09 AM |
| Discussion Spektrum AR6100E or Spektrum AR6100? | LaurenceGough | Off-road Cars | 23 | Aug 06, 2009 05:33 AM |
| For Sale Parkzone 5ch DX10 w/Receiver ch54 | CarlHill | Aircraft - General - Radio Equipment (FS/W) | 7 | Jul 10, 2009 12:07 PM |
| Discussion Can I use a Spektrum Air RX with a Spektrum Surface TX? | Bigmaxy | Radios | 1 | Jan 19, 2008 07:57 PM |
| Sold GeForce 8400Gs PCIx DX10 video card | GFBurke | Non R/C Items (FS/W) | 6 | Sep 05, 2007 10:43 PM |