Urban FPV Question

[Darren]

Hi,

I'm trying to get into FPV, just I'm going to gather as much research before I decide to make any purchases. First off, I will be flying in generally urban areas, as I live in San Diego, California. My initial thought is 1.3 GHz because it is not used very often, not as much interference etc. So, would 1.3 GHz be best for me given my circumstances?
I'm a bit reluctant to buy it because I feel that it is much more uncommon.
Second thing is power. So for sure I'm going to be getting a 9dbi patch antenna for longer range, but I'm unsure of the power. I will be flying a 4' wing, and preferably I wan't to be able to get as much distance I can (don't really care about vertical, I prefer proximity). So 300 mW in theory gets less distance but also consumes less energy and weighs less than a 500mW, Right? I will be using a gopro for video by the way.

Sorry for being a noob guys, just want to get my facts straight before I invest.

 

[lobstermash]

Extra power doesn't necessarily equal extra distance. Antennas are more important. Also have a check what you can use legally. I don't know much about US radiotelecommunications law, but I believe I've seen from numerous sources that 910Mhz is perfectly legal.

 

[Brian fred carr]

Never apologize for being a noob Darren ,we were all noobs once...the 5.8ghz FPV gear seems to be coming ever popular and may be worth a look....Its as lobstermash said its antennas that make the biggest difference check out bmsweb tube channel for a great and easy clover antenna build.....keep flying

 

[colorex]

Another thing to remember is the size of the antenna - 900MHz have really bulky antennas, slightly bigger than your hand, while 5.8 GHz antennas are smaller than half your fist.

 

[Darren]

Really I could go any way with this, but I'm going to rule out 900 Mhz because I have heard that it gets noise in urban areas. 5.8 Ghz would work however I've heard it is more influenced by obstacles, which definitely does not suit me because In dangerously low areas and through stuff. Has anyone had specific experience flying between obstacles with 5.8 Ghz? 1.3 ghz would be great with a clover antenna but how much range would be expected from a 300mw 1.3 ghz system? A 500mw? I know the distance gain if the mw is doubled is root 2. So theoretically 500 mw is 1.1785 times the range of 300mw (2y = (root 2)(5/3)). So thats hardly anything so therefore for my situation 300 mw will be probably better. I am getting this stuff right?

 

[lobstermash]

Also keep in mind that 300mW on 900Mhz is not equivalent (in terms if range) to 300mW on 5.8Ghz (assuming they've got equivalent aerials)

 

[colorex]

David Windestål uses 1.3GHz I believe. But HobbyKing doesn't have that available, and I don't know if it's legal in the USA.

 

[bmsweb]

I've heard it is more influenced by obstacles, which definitely does not suit me because In dangerously low areas and through stuff.

Keep in mind this isn't really an issue if you're using a 2.4ghz RC TX because even 2.4 doesn't seem to like going through obstacles, I've been doing some low flying between trees etc which I will post next time. My FrSky module starts beeping away warnings as soon as I get behind trees etc and video is lost for a moment but I'm out in no time so it doesn't really matter. Having said that there is no way I'm going to fly behind building with a 2.4Ghz RC TX because I'll be down and out in no time. So for me at the moment 5.8 is the perfect frequency.

If I decide to go UHF for the RC TX then I'll re-visit my VTX.

Well that's my $0.02 worth

 

[saundw]

Rangevideo all the way. They are great quality for a little bit more expensive. I have placed many orders with Rangevideo and I am very happy with their service and overall quality. All of their Tx come with inverted vees which is an added bonus.

Tx- http://www.rangevideo.com/index.php?main_page=product_info&cPath=35_36&products_id=229
Rx- http://www.rangevideo.com/index.php?main_page=product_info&cPath=35_36&products_id=232
Patch Antenna- http://www.rangevideo.com/index.php?main_page=product_info&cPath=37_39&products_id=69

 

[Darren]

Ahh. So many variated opinions. I'm leaning towards A 1.3 GHz 300 mw. A 800 mw seems a but unneeded given that my Frsky module gets around a mile of range. 900 MHz seems like it would get interfered. 5.8 seems great but again I'm worried about reception in shrouded areas. (yes I realize 2.4 GHz doesn't perform well either in covered areas). I honestly don't know, this is frustrating. I just want to be satisfied with my purchase and I don't want to regret it.

So I've narrowed it down to 1.3 300mw and 5.8 200 mw. What are some in depth pros and cons?
I want to fly through things using my 2.4 ghz rc tx with my wing.

 

[Nonamerc]

The formula you are using is not always right.

Sometimes the more mw is more RF noise which results in lower range. Keep that in mind!!!!

 

[Nonamerc]

If you are going to do urban FPV you will find yourself in the situation that your video signal will need to go through houses and trees. You should go for the 1.2 GHz stuff from readymaderc. With spektrum you wont get good singal my friend flew about 1Km above a small town and he often got failsafes. I recommend that you buy a LRS. If you are going for 900 MHz or 1.2 GHz I recommend that you buy Scherrer or EZuhf, you should not buy dragonlink or chainlink because they don't have a good filtering on these frequencies.

Arman, Nonamerc

 

[colorex]

If you are going to do urban FPV you will find yourself in the situation that your video signal will need to go through houses and trees. You should go for the 1.2 GHz stuff from readymaderc. With spektrum you wont get good singal my friend flew about 1Km above a small town and he often got failsafes. I recommend that you buy a LRS. If you are going for 900 MHz or 1.2 GHz I recommend that you buy Scherrer or EZuhf, you should not buy dragonlink or chainlink because they don't have a good filtering on these frequencies.

Arman, Nonamerc

I have a similar question - I have been considering all the options for FPV here in South America, and it looks like 900MHz is out of the question. 5.8 GHz is also quite a bit more expensive, offering less range at similar power.

I'm actually considering buying a 1.3 or 1.2 GHz system. Will this interfere with a Spektrum 2.4 radio? Is there a complete kit available (Tx, Rx, good camera, and cables) or do I need to get stuff from different places? I have heard good things about the Sony 1/3" from HobbyKing, but I have no clue if it will be compatible...

You seem to know this stuff, so, I ask you...

 

[Hamdhan]

I am with Nonamerc on that one, EzUHF are better suited for the job.

I'm actually considering buying a 1.3 or 1.2 GHz system. Will this interfere with a Spektrum 2.4 radio? Is there a complete kit available (Tx, Rx, good camera, and cables) or do I need to get stuff from different places? I have heard good things about the Sony 1/3" from HobbyKing, but I have no clue if it will be compatible...

IMO: The 2.4Ghz and 1.3/.2 are different, hence they will not interfere, however, it is possible that if the antennas are placed close to each other, one might over power the other as the waves will cancel out as they hit each other, so just keep them far apart. The FPV antenna might transmit so much power (signals) that your weak Tx signals (in long range) become inferior to it.
This is just an assumption/hypothesis. Now... lets wait from Nonamerc.

 

[colorex]

IMO: The 2.4Ghz and 1.3/.2 are different, hence they will not interfere, however, it is possible that if the antennas are placed close to each other, one might over power the other as the waves will cancel out as they hit each other, so just keep them far apart. The FPV antenna might transmit so much power (signals) that your weak Tx signals (in long range) become inferior to it.
This is just an assumption/hypothesis. Now... lets wait from Nonamerc.

900MHz and 2.4GHz, however, have been known to have resonant frequencies which reduce the range a bit. I'm not that much for range, just under a mile with the Bixler - and less than a half a mile with the multicopter. With the multicopter I'd like the ability to go down in between trees and obstacles without getting lockouts.

 

[Hamdhan]

You could ask Trappy. The FPV expert. If you can afford it, why not buy from Trappy himself?

 

[colorex]

If you can afford it, why not buy from Trappy himself?

I can't afford it.

 

[Hamdhan]

1.3: More range with same amount of power
5.8Ghz: less range with same amount of power. Even lesser with less power.

 

[Nonamerc]

Yea ofcourse,
Ok this is how stuff works:

If you have a new spektrum radio you are going to be alright because that version has good filtering. What you DONT want to buy is lawmate. Yes I know lawmate has a really big name in the fpv industry but I heard from Tim (readymaderc) that some of their products are not from high quality the last time. So I advice you to buy this:

ReadymadeRC 1.3GHz 300mW V-TX (Smaller then you think)
http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_30_38&products_id=1016

ReadymadeRC 1.3 GHz Vee Antenna (for on your V-TX)
http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_52&products_id=301

ReadymadeRC 8dbi optimezed patch antenna for 1280MHz:
http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_52&products_id=417
Or if you want to spend some more money:
http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_52&products_id=378

You can also get the helicals but you will get a very narrow beam with it. (I advice to use it with a tracker but I am asuming you dont have one)

For the receiver:
1.3GHz Receiver w/SAW filter
http://www.readymaderc.com/store/index.php?main_page=product_info&products_id=1020

If you are using a saw filter you will get less interference from your spektrum

Transmitter Cable:
http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_66_67&products_id=135
Just solder a servo plug on your camera and its plug and play.

Low Pass Filter
http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_52&products_id=484
This thing will filter out your 2.4GHz noise on your 1.3GHz system

This is my setup. (Don't have the Vee Antenna and the low pass filter because it was BK)

Also it's really important for your V-TX and your RX to be apart as much as possible. I am making a video about that, it will be posted on my youtube channel. (In this video I am placing the ezuhf in my bixler. Will also work with your spektrum)



Youtube channel:

youtube.com/nonamerc

Greetings Arman

I hope I helped you out!

 

[colorex]

Thanks Arman!

Looks like I'll have to save up some more if I want a better system... But it seems like it's worth it!

What is the simplest (cheapest) combination of the above? Is it not good enough to start with if it is as simple as camera-VTx-VRx-monitor?

Is this camera compatible with the above VTx?

http://www.hobbyking.com/hobbyking/store/__13434__1_3_inch_SONY_CCD_Video_Camera_NTSC_.html