Should I get a better radio?


#1

Hello all.

I have my setup on a 100 foot tower on a high spot in Florida (about 120ft above sea level) so on average I can see about 260 nm on average out. I currently have a Pro-stick plus on a Raspberry PI 3+ and it seems to be doing ok. I was about to try to put up a tinkerboard with a airspy and see if I got any better results but while the rig was being tested on the bottom of the tower, the tower was hit by lightning and it went down the Ethernet cable taking out just about everything attached to the tower.

So at this point I have replaced my main rig with the same pro stick and Raspberry PI 3+ but I am wondering if I should even bother getting another airspy as the equipment would be about $200.

At the moment I get during the busy times about 1400 messages per sec and I just wonder if I am going to get anything useful with better radio.

Ideas?

dump1090-localhost-local_rate-1h
Capture


#2

my advice is to retire from the flight tracking business and send your tower to me (prepaid of course)…your skyview image is beautiful and appears to be very omnidirectional. 1400 msg/sec would send me into a state. i have no advice re your question but did wish to express my general jealousy regarding your installation.


#3

Try a rtl-sdr dongle + LNA combo next. Quite a bit cheaper :wink:

For me the message rate didn’t go up too much but i’m limited at 200 nmi because of the horizon.
I mean if you want to try something new and only lose maybe 60$ or so that’s what you should go for :slight_smile:

Which LNA did you use for the airspy mini?

Also: robust tower, do you have pictures of the damage to the ethernet cable or did it evaporate?


#4

i also use and rtl-sdr dongle and their 1090 LNA. i use an external bias-t (minicircuits) and external lab power supply for the bias-t as i don’t trust the typical RPI power supplies. my directional coverage is limited by, as Lynyrd Skynyrd would say “Oak tree your in my way”.


#5

see david baker post 29 august of 2018 re radios


#6

Happy to see hear you are still alive. You already know that Florida is the lightning capitol of the world. Stop playing with cables during the storms.


#7

I figure I should post a little of the damage, at least I get something for the replacement costs and climbing costs…

It is an old Rohn25 which was used for the Orlando Sentinel Newpaper paging system. I wanted to have Internet out of the middle of nowhere and to get over the pine trees I need a tower. So I get to use it for other fun things too, like this flightaware.

Ethernet surge “protectors”

POE injectors
IMG_20180930_175629

And the tower


#8

I suggest doing ok is understating your success.

That is really, really impressive.

From this can we assume you normally have the receiver at the top of a 100’ tower?

If the answer is Yes then my suggestion would be rest on your laurels.

From both my own experiences and observing others in various ADS-B discussion boards there is a virus that can infect the hobbiest. Nothing is ever enough!

My radios and computers are in the roof space and very easy to get to and the antennae are just above the roof line on TV masting and also relatively easy to adjust or replace. I swapped out a radio and filter last night and it took me all of about 3 minutes.

Climbing a 100’ tower on the other hand is expeditionary and not something to do lightly. How long would it take you to change a radio or a filter or an antenna up there?

Personally, I’d mount another antenna at about 15’ and do all my comparisons at that height until I was really, really sure there was any point in changing stuff at the top.

S.


#9

Thank you and for a link if anyone else is looking for the answer. TLDR - “maybe a 10% gain”

https://discussions.flightaware.com/t/gain-again/39687/17?u=simtra


#10

It’s not only with ADS-B hobbyists. I see the same with amateur astronomers, the ‘aperture fever’, and with hamradio operators, the ‘cloud warmers’, just to mention two other groups.


#11

Yes,they are on the top of the tower so that I don’t lose much signal with a 100’ cable as I tried that and was just better on the ground. I also tried a very long active USB cable to the top and there was too much power drop on the cables without running power to the top.

For a small tower climb, this is not too bad. The gear takes a few minutes to put on and if I am not trying to kill myself by free climbing, it maybe takes about 10 minutes to get up and 10 back down. But it is one heck of a work out so I try to batch my climbs when I can. That being said, I have helped my out WISP and he has a few 500 foot towers and those will wear you out.

I’ll most likely look at and LNA like the other have recommend and test it near the ground as I did before I lost my airspy.


#12

I would not send Ethernet up there, rather use a WiFi router and connect to it. All that needs to go up there is just 9-12V power to a 5V voltage stabilizer to feed the Pi. That power can be easily grounded (negative wire for example).


#13

I tried that. I got a 12V power supply and a buck converter to lower the voltage. The only problem was the electrical noise from the buck converter was just flooding everything. I ended up just ripping it out as I might as well just have the radio on the ground at that point. In my case anyway, I already have Ethernet on the top of the tower anyway as my WISP radio is up there.


#14

One that is properly shielded, of course…
Personally I will try my luck with this:


Enclosed in a ferrous can (they still make those for vegetables).

The Ethernet cable is very hard to protect at high levels of energy. That’s all…
But yes, the tower is sweet. I have tall trees around me too, that’s why I am contemplating ways to get above them. Without breaking any local ordinances.


#15

hello dxista, you are right re amatuer astronomers. i have a 10" SC and when i take the thing outside i end up with bruises just trying to lug it outside and put it on the tripod…so now i have “plane count fever”…at least no bruises so far (ie i haven’t fallen off the roof yet!)


#16

I have a 6" Dobsonian Reflector, and it’s already too much of a hassle. The BEST telescope is not the one with the biggest aperture, but the one that gets used regularly.


#17

I know the feeling but my astronomy involves travel and viewing with the naked eye rather (ahem, sorry just clearing my throat) than buying expensive telescopes.

Last year the trip to Jackson Hole Wyoming to view the total eclipse of the sun was my fourth. It was spectacular and we followed it up by a trip to Alaska to see the Northern Lights amongst other things.

The previous one was a 4000km plane trip to Cairns and all we saw was clouds.

The one before that was a three day drive to a remote desert location in Central Australia in 2004. Also spectacular.

We have just booked for Patagonia in Dec 2020.

And then there are the trips to the spectacular Leonids meteor shower, and all the good comet viewings.

Don’t ask me about Halley’s comet!

At least last month’s Total Eclipse of the moon was viewed and photographed from my own back yard.

To make matters worse, I have or had an Amateur Radio Licence in three countries and an adequate supply of equipment.

Hobbies?

S.


#18

Now you are talking!:wink:

The best astronomy investment is a quality 10x50 binoculars.