How does the 2.4ghz, 5.8ghz & 1.2-3ghz works?

[abonto]

Hi guys,

I'm not sure if I'm posting this on the right thread, and I'm sure this was discussed before, but I just want to bring this up because I'm still puzzled. Sorry, it might sound newbie, but I'm used to the old school crystals or Mhz where I know my channel and I know who I'm conflicting with.

Anyway, I crashed my quad this weekend filming a local commercial. My quad flies great and far with just the 2.4ghz Futaba T7c radio, but after I put the 1.2ghz 800mw transmitter(which came the day before the shoot), I lost control of my quad after about 50 yards then crash,,, I flew it again afterwards without the 1.2 video transmitter and it was great. Now after searching the internet, I found out that there's a second harmonic that conflicts with the radio, saying 1.2ghz x 2 = 2.4ghz, and conflicts with the 2.4ghz receiver, now I believe this. But if this is the case, why is it that my 3 home phone which is 2.4ghz and my internet 2.4ghz wifi with 5-7 connection, doesn't conflict with my radio? Also, how do the radio knows, it's tuned & connected to the receiver and not the rest. I also see several people flying together and they're all on 2.4ghz, but have no idea what channel they're flying on and still not conflict with each other. Sorry guys, I just bind this and fly.

Can somebody point me to the right direction on how all these works together? Thank you in advance...


I fly:

DJI 450 with TBS body & 550 NAZA with GPS
Futaba T7C with skyflier receiver
3300 3S 25c batteries
Go-Pro 3 HD
Savox Servos for Gimbal

 

[02deuce]

If your running 1.2 -1.3 VTX and 2.4 control, be sure to run and low pass filter. Be sure to range test with any set up. If your RTH is setup correct you should not have crashed when you lost radio signal. Without getting into the technical side of it, 2.4 was designed for multiple users flying in a close proximity with no interference. Electronics placement is always the key to non conflicting issues, be sure to place you VTX and RX and far from each other as possible.

http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_58&products_id=484

 

[kloner]

ouch, yes the 1280 vtx's screw with rc control without the filter inline, it attentuates the signals outside it's rating. 1280 also sucks butt near gps flight controllers. makes locking sats take longer, makes it randomly loose signal from time to time and you'll see red flashing

You really didn't want 1280, 5.8 is perfect for most framing,,,,, if you really need a quality link, get ezuhf for the radio and use 2.4 for the video feed. That's the expensive way, but the best for most areas.

You are conflicting digital signals and composite signals, neither can see each other, they just make interference

 

[Phil550]

Hi guys,

I'm not sure if I'm posting this on the right thread, and I'm sure this was discussed before, but I just want to bring this up because I'm still puzzled. Sorry, it might sound newbie, but I'm used to the old school crystals or Mhz where I know my channel and I know who I'm conflicting with.

Anyway, I crashed my quad this weekend filming a local commercial. My quad flies great and far with just the 2.4ghz Futaba T7c radio, but after I put the 1.2ghz 800mw transmitter(which came the day before the shoot), I lost control of my quad after about 50 yards then crash,,, I flew it again afterwards without the 1.2 video transmitter and it was great. Now after searching the internet, I found out that there's a second harmonic that conflicts with the radio, saying 1.2ghz x 2 = 2.4ghz, and conflicts with the 2.4ghz receiver, now I believe this. But if this is the case, why is it that my 3 home phone which is 2.4ghz and my internet 2.4ghz wifi with 5-7 connection, doesn't conflict with my radio? Also, how do the radio knows, it's tuned & connected to the receiver and not the rest. I also see several people flying together and they're all on 2.4ghz, but have no idea what channel they're flying on and still not conflict with each other. Sorry guys, I just bind this and fly.

Can somebody point me to the right direction on how all these works together? Thank you in advance...


I fly:

DJI 450 with TBS body & 550 NAZA with GPS
Futaba T7C with skyflier receiver
3300 3S 25c batteries
Go-Pro 3 HD
Savox Servos for Gimbal

Here's a link which explains 2.4G:

http://www.buzzflyer.co.uk/2.4G-RC-Guide.asp

 

[abonto]

If your running 1.2 -1.3 VTX and 2.4 control, be sure to run and low pass filter. Be sure to range test with any set up. If your RTH is setup correct you should not have crashed when you lost radio signal. Without getting into the technical side of it, 2.4 was designed for multiple users flying in a close proximity with no interference. Electronics placement is always the key to non conflicting issues, be sure to place you VTX and RX and far from each other as possible.

http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_58&products_id=484

Thanks 02deuce. I bought a 5.8 instead.

 

[abonto]

Here's a link which explains 2.4G:

http://www.buzzflyer.co.uk/2.4G-RC-Guide.asp

Thanks Phil and Cloner...I have a lot of research and reading to do .

 

[02deuce]

Nothing wrong with 5.8, I use it as a repeater from 1.3, that way I'm not wired to my Dominators. The only downside to 5.8 is you don't have the range or transparence that 1.3 has to offer. I love flying behind trees and obstacles with out loosing video. Each frequency has its restrictions, Its just an matter of finding the right one for your location and flying style.

 

[abonto]

Nothing wrong with 5.8, I use it as a repeater from 1.3, that way I'm not wired to my Dominators. The only downside to 5.8 is you don't have the range or transparence that 1.3 has to offer. I love flying behind trees and obstacles with out loosing video. Each frequency has its restrictions, Its just an matter of finding the right one for your location and flying style.

Thanks Deuce, I think I'll keep both and just buy the low pass filter. And thinks Phil, that link gave me a whole lot of insights.