1.5 miles / 2.44km - Phantom 1 w/ FatSharks

[Howzit]

Did another 'long distance' run today. Goal was to best my last flight of 1 mile, but using a Helical antenna this time. Let me tell you, the Helical is LOADS better than than standard SpiroNet/cloverleaf. Video was crystal clear the entire way, up until the turn around at the 1.5 mile mark. Had some break up (complete loss) for about 20 seconds, but it cleared up as I made some progress home. At this point, I think my video is out performing the stock Phantom transmitter.

Going to put a fresh set of batteries in the transmitter and shoot for 2 miles next. May end up adding a second battery just to be safe. Landed at 10.8v, recovering to 11.3 volts within about 30-60 seconds or so (according to iOSD). Had a pretty strong headwind that put a hurt on battery while getting out there.

[youtube]http://www.youtube.com/watch?v=HuQit6zJQcg[/youtube]

 

[Diesel31]

I'm convinced. I'm just not completely clear on the turns. Can you drop some knowledge? It looks like you have a 5 turn. Why that over a 3 or 10? I'm ready to pull the trigger, but want to make an educated decision.

Also, RHCP or LHCP? I ordered some Attitudes and don't have them yet, so pardon the noob question.

 

[Howzit]

I'm convinced. I'm just not completely clear on the turns. Can you drop some knowledge? It looks like you have a 5 turn. Why that over a 3 or 10? I'm ready to pull the trigger, but want to make an educated decision.

Also, RHCP or LHCP? I ordered some Attitudes and don't have them yet, so pardon the noob question.

I don't really know all the technical schnaz between the amount of turns, but I figured a 5 turn still provided a large enough angle of view, while still being small enough for the head. Most of the circular polarized stuff seems to be RHCP, so I would probably stick with that if you have the choice between the 2. I have a SpiroNet on the Phantom, but any of the IBCrazy or TrueRC cloverleaf style antennas should work great.

I just wish I had a DVR to record the actual FPV footage. Thats coming soon, hopefully.

 

[Newlineliving]

I notice a lot of these recording are over open areas where there is not a lot of EMF's what is it like over populated areas? or over a large body or water. I am in Norther California and when I take my Phantom out to the coast for some over the ocean flying the FPV on my cell is not as good as it is in my neighborhood. Is that weird? Oh and by the way I am nowhere near 1.5 miles. I lose video at about 800ft.

 

[DeweyAXD]

That all makes good sense. Helicoil are much more powerful than Cloverleaf because they are focusing the 'beam' much narrower. Cloverleaf (or Spironet as Immersion call it) sends the signal out in all directions.

Helicoil are great but you HAVE to keep your antenna pointed at the Phantom, if you look away beyond a certain degree you will loose signal. Easy when you have line of sight, not so easy when you are 1.5 miles away.

The other important downside to helicoil is that if you fly over your head or behind you and you are not looking at your Phantom you will likely loose most, if not all of, your signal.

For that reason this is why the best possible long range set up is one with diversity switching. That means you effectively have 2 antenna and your Goggles and or monitor are delivered the best signal from the one with the strongest signal. So what you do to be clever is have a Helicoil on one antenna and a Spironet on the other.... covering both near and far.

If you want to get really into long range (like 20 miles.... which you won't on anything other than a plane!) that is why people do motorised antenna trackers. These point a helicoil at the craft and follow it based on signal even when you have noooo idea where it is.

what is it like over populated areas? or over a large body or water

The further you go the more interferance you suffer so populated areas will be worse (due to cell phones, Wi-Fi and all sorts of crazy radio waves). With 5.8ghz you also HAVE to have line of sight as the frequency waves are smaller and don't penetrate objects well at all (if at all). Over a large body of water you should be fine as long as you can keep pointed in the rough direction of the Phantom (especially if using Helicoil).

As for the number of Helicoil turns that comes down to beam width. The more coils, the tighter the beam and hence the more accurate you need to be at pointing your antenna at the Phantom.

Final note of course is that most countries air associations don't allow legal flight beyond line of sight so if you brown out, crash and someone gets injured (along with the recording) you can expect to get your knuckles wrapped (and likely an example made out of you by the authorities just to teach others the lesson these days). Open fields are your friend! Populated areas are not! :lol:

 

[hjscm]

I notice a lot of these recording are over open areas where there is not a lot of EMF's what is it like over populated areas? or over a large body or water. I am in Norther California and when I take my Phantom out to the coast for some over the ocean flying the FPV on my cell is not as good as it is in my neighborhood. Is that weird? Oh and by the way I am nowhere near 1.5 miles. I lose video at about 800ft.

where are you flying? sometimes on the coast there is a lot of interference. i can get 1.3 miles in my neighborhood but when i go to pacifica or half moon bay i can only get about 4,500.but my tx is my limiting factor video is fine on 5.8 and 1.3. if you are close we can meet up and fly at the coast sometime

 

[Howzit]

Tested the battery with a multimeter right now and it's reading 11.21

I'd say 1.5 miles is just about the limit of the the MadDog 2700mah + P2 prop setup. Theres a tad bit of 'safe' energy left, so I may try for 2 miles on a calm day. I'll probably turn off the voltage alarms too. Better a ruined battery than a lost Phantom, eh?

 

[Whiteram]

Tested the battery with a multimeter right now and it's reading 11.21

I'd say 1.5 miles is just about the limit of the the MadDog 2700mah + P2 prop setup. Theres a tad bit of 'safe' energy left, so I may try for 2 miles on a calm day. I'll probably turn off the voltage alarms too. Better a ruined battery than a lost Phantom, eh?

+1 Batteries a bit less expensive Id say...

Honestly think your getting longer flight time with the MadDog 2700 mah over stock 2200?

 

[Howzit]

Tested the battery with a multimeter right now and it's reading 11.21

I'd say 1.5 miles is just about the limit of the the MadDog 2700mah + P2 prop setup. Theres a tad bit of 'safe' energy left, so I may try for 2 miles on a calm day. I'll probably turn off the voltage alarms too. Better a ruined battery than a lost Phantom, eh?

+1 Batteries a bit less expensive Id say...

Honestly think your getting longer flight time with the MadDog 2700 mah over stock 2200?

I haven't tested the MadDog vs. Stock battery alone, but I did a p2 prop + mad dog 2700mah vs. stock battery + stock prop hover test and saw a 4 minute improvement. I'd venture to say the p2 props are worth 2 mins and the mad dog is worth the other 2 (give or take).

[youtube]http://www.youtube.com/watch?v=83c3VzOHKag[/youtube]

 

[LuvMyTJ]

Have a look at this video for an great explanation of how different types of antenna work. He has other informative videos along with several on helical antennas. Worth the subscription cost

FPV antenna gain and range explained...
https://www.youtube.com/watch?v=Bx7gMUw1MGw