Sex, Lies and Roof Top Antennas!

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Ok, ok, I lied! This isn't about sex, but since I finally got you to look at my post... I am trying to figure this out and am hoping that someone with wifi experience would check my work.

I am trying to mount a permanent antenna array on my roof that I can plug my P2V+ controller and repeater into and then fly FPV from inside my home.

Here's what I am thinking... Using a standard p2v+ (with the OEM 2.4 ghz repeater and 5.8 ghz contoller) along with: two 2.4ghz sunshans amps; two 5.8ghz sunshans amps; 2 6db antenuators; and a 100' of rg58 cable (because its cheap and flexible) to build a 50' run to a rooftop fixed antenna array to achieve significant fpv and control distances.

I used this calculator: http://www.saarsham.net/coax.html to determine db and power loss over 50' of rg58 cable.

I would connect the attenuator between the repeater and the 1st 2.4ghz 2000mw amp and then run 50' of rg58 to a second amp of the same power/frequency. This second amp would output through an omni-directional antenna. Supposedly, at 2.4ghz I would get 91mw entering the rooftop amp, which should be adequate. The bi-directional "pre-amps" in the sunshans amplifiers should make up for the 13db loss along the 50' cable (at 2.4ghz).

Likewise, I would connect the other attenuator between the 5.8ghz contoller and a 2000mw 5.8ghz sunshans amp, then run another 50' of rg58 to a second amp of the same power/frequency with 8 mw entering the rooftop amp (after a 24db loss through the cable). Again, this second 5.8ghz amp would output to an omni-directional antenna. I think that with a one-way 5.8ghz signal coming out of the 2nd amp that you would have sufficient gain to control the bird at distance - even with the 24 db loss along the cable.

With both the 5.8 and 2.4ghz antennas, I assumed a 1.5:1 swr omni directional antenna.

I have the bird and the amps, otherwise I would just switch to another frequency. I'd really like to get this setup (or similar) working. I know virtually nothing about microwave technology.

Now, wasn't that way more interesting than sex? LOL
Paul
 
Re: Permanent roof top 2.4 & 5.8ghz antenna array. Pls Help

paulgrenga said:
I am trying to figure this out and am wondering if someone with microwave experience would check my work. I am trying to mount a permanent antenna array on my roof that I can plug my P2V+ controller and repeater into and then fly FPV from inside my home.

Here's what I am thinking... Using a standard p2v+ (with the OEM 2.4 ghz repeater and 5.8 ghz contoller) along with: two 2.4ghz sunshans amps; two 5.8ghz sunshans amps; 2 6db antenuators; and a 100' of rg58 cable (because its cheap and flexible) to build a 50' run to a rooftop fixed antenna array to achieve significant fpv and control distances.

I used this calculator: http://www.saarsham.net/coax.html to determine db and power loss over 50' of rg58 cable.

I would connect the attenuator between the repeater and the 1st 2.4ghz 2000mw amp and then run 50' of rg58 to a second amp of the same power/frequency. This second amp would output through an omni-directional antenna. Supposedly, at 2.4ghz I would get 91mw entering the rooftop amp, which should be adequate. The bi-directional "pre-amps" in the sunshans amplifiers should make up for the 13db loss along the 50' cable (at 2.4ghz).

Likewise, I would connect the other attenuator between the 5.8ghz contoller and a 2000mw 5.8ghz sunshans amp, then run another 50' of rg58 to a second amp of the same power/frequency with 8 mw entering the rooftop amp (after a 24db loss through the cable). Again, this second 5.8ghz amp would output to an omni-directional antenna. I think that with a one-way 5.8ghz signal coming out of the 2nd amp that you would have sufficient gain to control the bird at distance - even with the 24 db loss along the cable.

With both the 5.8 and 2.4ghz antennas, I assumed a 1.5:1 swr omni directional antenna.

I have the bird and the amps, otherwise I would just switch to another frequency. I'd really like to get this setup (or similar) working. I know virtually nothing about microwave technology.

Thank you for your thoughts,
Paul


HOLY ****

someone get this guy a factory to mass produce this.. *sits and grabs some popcorn and waits for someone to give Paul answer *
 
Re: Permanent roof top 2.4 & 5.8ghz antenna array. Pls Help

THAT was funny

Thank you! :lol:
Paul
 
Re: Permanent roof top 2.4 & 5.8ghz antenna array. Pls Help

Sounds fun, sorry I can't help!
 
:D
 

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I thought about somthing like this and couldn't find any info on it. You seemed to have done a bit more homework then me on this. I think you are just gonna have to pioneer. I lost my bird to a flyaway so I can't help either. I'd love to hear about your results though.
 
I have been thinking about doing this as well. I of course have no experience whatsoever with this sort of thing. I would like to have it because I live in a rural area and in a wheelchair so it would be easier. Plus the ac in the summer not a bad thing either.

It sounds like you have it figured out. How much would you be out if it didn't work? If I could I would just lay it all out and try it and if it did not work you should be able to return most of the stuff. Hope it works out for you.
 
24db is a scary amount of loss.
 
Use Lmr 400 cable, a real Alpha adapter and choose model with N connector.. Choose 3 watt or better like the SH24Gi4000.
 
Would be good to see what the outcome is, I've also thought about a similar setup for a vehicle would be pretty cool(was thinking about big distances with big antennas tbh) [emoji16]
 
New the to forum here... Got a P2v+ on Friday and love it!

To answer your question, I'm also a HAM... K3BMW for anyone else that is a HAM as well. I can tell you with very good certainty that your weak link will be the RG58. Quick lesson in cabling. Spend your money on a good cable and a good antenna. Signal loss is very really and I've spent countless hours and money trying to get around buying good cable and I can tell you from experience its not worth it.

So long story short.... As you go up in frequency, you have more DB loss in a cable. RG58 is really only used in mobile installs of a radio where you're operating under 900mhz and you're making a cable run of 15' or less in my opinion. If you're going to run 50', you will want a bare minimum of LMR400 cable or higher. The other option is shortening your cable run. At 2.4 ghz and 5.8 ghz, your DB loss over 50' of RG58 is will almost make it impossible to transmit and receive. You'll be better off just using the stock controller and range extender from inside the house (obviously that won't get you very far....)

I love the idea, but you'll definitely want some good cable or make your cable run less then 10'.

Just my 2 cents. You guys can teach me about my new Phantom and how to modify it and I'll teach you all you want to know about radios, cables and antennas :)

73's!

Chris - K3BMW
 
Is there anyways to make a range extender work with the tx or rx? If so u could put the range extender and booster at base of antenna , say in attic under roof antenna and just fly from inside home. I did this with my FC40 but don't know if the P2V+ range extender can hook up to another range extender.
 
I have found a way to fly from inside my house. Garrock, (phantompilots screen name) has created a 5.8ghz repeater for the P2 and then I use the DBS ITelite antenna for the 2.4ghz side of things. I put them on a pole outside and then I can sit in my house and fly. Have been getting great results with this setup. I have flown 8600' away from my house and still had total control and video.
 
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I have found a way to fly from inside my house.
Berry... Congratulations! You are the first to do this type flight.
You blended your External Antenna Mods to a complete pole-mounted radio repeating solution (i.e. REDbird 5.8ghz RC Repeater and DJI 2.4ghz WiFi Repeater)

Wirelessly separating the Operator Control Point from the Comm Uplink Point is a fundamental concept to open up a whole new level of flight possibilities.

Only the DJI Phantom 2 Vision(+) can perform this type flight. Even though though the Phantom 3 and Inspire 1 have upgraded cameras and other new capabilities, they can't come close Accessing The Inaccessible.

*** The Phantom 2 Vision(+) has a whole new life to live. ***

After you do more flights, please share pictures and videos about your setup.
 
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ive been doing this all summer. I used 2 50' runs of lmr400 attached to 2 9dbi wifi antennas on my roof. Used 2 satellite mounts and about 10' of pvc pipe to get the antennas even higher. Ran the cable into the attic then down through the wall. The lmr is very thick so I have lmr240 from remote to 2 3watt suhans then from the suhans lmr240 again screw to the lmr400 in the wall. No attenuators. With this set up I have been out 15,000ft on a regular basis. Talked to tony with fpvlr and it just so happened as we were talking he was in the process of updating his site with a air side amp for the p3 for 99 bucks. He said in testing difference is night and day. I have one on the way. So paulgrenga, can you use 2 amps on the same line? One in the house close to the controller then another one on the roof just before the antenna?
 

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