remote transmitter antennas

Joined
Sep 25, 2016
Messages
26
Reaction score
1
I'd like to move the transmitter's antennas roughly 20-30ft away from the transmitter body, allowing me to 1) sit in a warm car and 2) put the antennas on a mast so they can clear some nearby trees

I have 800mw Mikrotik wifi cards in the transmitter and solo. I've also just ordered 2 Sunhans 3W wifi boosters.

I was thinking of doing this one of 2 ways; either keeping the transmitter wifi card in the transmitter:


, or moving it out of the transmitter so that it could be closer to the amps/antennas:

Are either of these setups preferred? And if the wifi card is pulled out of the transmitter, what kind of interface/cable could be used in A?
 
Joined
Mar 12, 2016
Messages
3,685
Reaction score
2,460
The latter would be the better way to do it. IF you can create that data cable going to the WiFi card that doesn't degrade the data, and you adequately protect the WiFi card in some kind of enclosure. Putting the card in an enclosure up on top of the mast adjacent to the antennas is ideal, as it eliminates the challenges of long, lossy coax.

If you can't overcome the data cable thing, long coax is generally simple. But to get quality coax that isn't lossy at 2.4ghz, you're looking at expensive stuff. There is no free lunch.

For the antennas, I would suggest omnis of no more than 6db gain.
 
Joined
Oct 11, 2016
Messages
99
Reaction score
15
Age
37
They start to get very directional over you get past that gain. Better to have a more omnidirectional pattern with lower gain.
 
Joined
Oct 8, 2016
Messages
93
Reaction score
31
Location
Melbourne, Australia
If you already have the Microtik I'd leave the card inside the tx. But the amps should always be as close as possible to the antennas. Keep the ant gain low... i'd even suggest 3-5dBi is even safer (depending on what altitude you intend to fly at), with a 3W amp you'll already be over FCC limits (max EIRP is 4W)
Also, I'm not sure how you'd go extending the mini-pci bus (shame it's not USB interface... that'd be perfect for this application)

At 20-30 feet, you'd want to be using LMR-400 or equivalent cable... which isnt cheap, although you'll probably get away with LMR-195 if the amps have good RX gain.

Also remember if you're flying in populated areas, there's likely to be lots ot 2.4GHz noise. When the Solo is at altitude, it'll hear lots of noise. The higher up you put the tx antenna, the more it'll get also, so you'll need to find a balance. Too high could actually hurt.
It's a shame the solo tx doesnt have a built in wifi survey tool.

FYI my remote ant setup is just a basic 5dBi omni I mount to the roof racks of my truck, with about 12' of LMR-195 cable and Microtik cards. With cable loss this give me an EIRP of about 2W, plus the benefit of the roof of my car acting as a ground plane.
 
Joined
Sep 25, 2016
Messages
26
Reaction score
1
thanks @Dogman1973, as far as I can tell I'd be looking at > $1500 for extending the pcie bus at those distances, so I'll go with LMR-400 and keep the wifi card in the transmitter.

As far as the antenna mast goes, assuming the antennas themselves are roughly 10-20cm away from the mast, does it matter whether the mast is metal or not?
 
Joined
Oct 8, 2016
Messages
93
Reaction score
31
Location
Melbourne, Australia
You may get away with LMR195... I'm not familiar with that amp, but if it has decent RX gain (say > 15dB), you wont need 400.

As long as the radiating part of the antennas aren't in the same horizontal plane as the metal mast you'll be fine.

eg:
 
Joined
Oct 8, 2016
Messages
93
Reaction score
31
Location
Melbourne, Australia
I only run one... diversity up on masts wont help much, although with amps with good rx gain, maybe a little benefit.

Forgot to mention, the diversity is RX only, from memory on the microtik the tx is on port 0.
 
Joined
Oct 28, 2016
Messages
20
Reaction score
3
Age
56
thoughts on using a external wifi card antennae setup powered via a usb cable...whats the record for wifi last I heard was over 200 miles.
 
Joined
Mar 12, 2016
Messages
3,685
Reaction score
2,460
Ugh. Guys, it is not diversity. It's MiMo. YOU NEED BOTH ANTENNAS. Which yes, double the cost of the expensive low loss coax. But that's the nature of the game.
 
Last edited:
Joined
Oct 8, 2016
Messages
93
Reaction score
31
Location
Melbourne, Australia
sorry should have clarified, pedals is correct... if you want it to stay in N mode, then yes both antennas would be required.

Mind you I havent exactly pushed the range limits (havent gone beyond visual) using one antenna in G,
 

New Threads

Members online

No members online now.

Forum statistics

Threads
12,053
Messages
140,858
Members
13,980
Latest member
Amsecure