Site improvements

[tomvdhorst]

In the last few months I’ve been busy with an upgrade to the house getting new window frames and new glass for these frames due aging and sustainability. The old frames made of aluminium were 40 years old and a lot of the windows were single pane glass. In the winter this could mean cold creeping in through the sealing of the window frames and having to heat the house more when it got cold.

A positive thing was that I was able to keep the sites I have running indoors including the antennas since the single sheet glass wasn’t really killing any signals coming from outside. Surely there was a limitation but that was ok. Living on a 3rd floor of a 9 story apartmentbuilding has its limitations.

When the new windows arrived I got tripple layered glass and that glass was coated as well.

This lead to a 60% decrease in the signal strength overall and that did hurt the number of positions and aircraft a lot.

Sites that used to be around 300.000 positions a day went down to 100.000 and the aircraft numbers dropped from 2300 on average to 1200 on average.

So it was time to act. After checking with the head of the household we decided to move all the antennas (I have 23 sites) outdoor to 2 balconies so we could free up the windows on the inside and to improve reception in exchange for some pairs of shoes so we are both happy now

I’ve listed some things I’ve done to get to the situation below. Bear with me, this is a lengthy post

This is not to brag about it but maybe it can help somebody to see what effects things can have on your reception. I’m a nerd and I know it so don’t think that this is normal to have that much sites or time and effort to put into it. This is a major hobby for me.

Part of the move was getting new cables where needed and the replacement of 2 antennas for new ones.

So I ordered the replacement cables (H155 Coax), 5x 15ft and 5x30ft in order to get the antennas to their desired spot on the outside.

As replacement antennas I chose the Vinnant COL1090/11-PEL and the Vinnant Yagi antenna Y13E-1090.

Last week the items arrived and I started to get all the stuff into place, drilling holes in wooden window frames that remained after the renovation (only the glass in these frames was replaced) and getting the cables to the outside. Working one balcony at the time I was able to minimize downtime for the setups to and hour or sometimes a little more. One of the balconies is only 4x4ft, not used by either me or the head of the household for any things regularly. The other balcony is the bigger one that we use during spring, summer and fall when the temperatures are allowing it.

The last thing I did was putting the Yagi antenna into it’s position. Since it is a directional antenna I aimed it at EHAM airport, that is only 8 NM away from my home.

In addition to the longer cables I also got Wideband LNA’s from China https://nl.aliexpress.com/item/1005007797771912.html?gatewayAdapt=usa2nld4itemAdapt and used those on the sites that got longer cables and are using a 1090Mhz filter. When not using a filter it is no use since the SDR will be overwhelmed by the signal and will go “deaf”.

Here are some results of the move outside from different setups.

First a Raspberry Pi3 with and FA Prostick Plus, LNA, FA 1090Mhz dark-blue filter and the COL1090/11 antenna. This site is connected with a 15 ft cable.

Both positions and aircraft have improved quite a bit due to the move outside and the new LNA and antenna.

Secondly the site with the new Yagi antenna. In the old configuration it ran on an old black radarbox dongle with a 7 cm antenna with no LNA or filter. This is connected to a raspberry Pi 3B

In the new configuration it has a new radarbox dongle, 10 ft of H155 cable and the Yagi antenna. Reception on the system has improved massively , going from 50.000 positions per day to 300.000 positions per day, aircraft count increased from around 800 to 2200 per 24hrs. Also the antenna is catching more traffic from directions I didn’t expect so that is an added bonus. The range increased form 60NM to 200NM

The antenna is oriented to the WNW but catches also traffic from other directions.

As a third example I have an antenna that got a 30 ft cable on the other side of the building.

This example shows the old situation, after the improvement but still inside and the new location outside.

The equipment here is a FA SDR, wideband LNA, FA 1090Mhz dark blue filter, 30 ft of cable and a Vinnant COL1090/7.5P antenna.

The improvements are all across the board on all setups.

I went from 40.000 aircraft a day on all systems combined to 53.000 aircraft in the new setup and that might even get better once the GA season starts since the small aircraft are mainly staying at the ground at the moment due to the weather still being cold, windy and snowy from time to time. We should get better weather on the way if I should believe the weatherman but you know they predicted, they can’t forecast

So how does the antenna farm look then

This is the small 4x4 ft balcony with all antennas placed on the railing. In total there are 17 setups located there, including the Yagi antenna at the right hand side.

Antennatypes are FA 5.dB, Vinnant COL1090/5-S, a Vinnant COL1090-8/P, a Vinnant COL1090/9-PSE, a Vinnant COL1090/9-PEL, the Vinnant COL1090/11-PEL and the Vinnant Yagi antenna.

On the other side of the building I created this

Antenna types here are from left to right

Vinnant COL1090/5-S (2x) FA 5.5 dB antenna, VInnant COL1090/5-P, Vinnant COL1090/7.5P and a VInnant COL 1090/9P at the utmost right just behind the wall.

I learned some valuable lessons in the move of these setups that might be beneficial when you want to improve your reception. Some are obvious but still noteworthy:

• If possible setup your antenna outside, the reception will be better in the open air then when indoors. Weatherproof your connectors when setting up, you will regret it later if you haven’t.
• Invest in good cables. Don’t settle for crappy coax if you are able to get some decent H155, LMR240, LMR400 if you get longer coax distances.
• Use filters when you deploy wideband LNA or you will kill your signal coming into the SDR.
• Not all dongles like the addition of an LNA. FA dongles are working fine, the generic ones https://nl.aliexpress.com/item/1005004832658212.html?gatewayAdapt=usa2nld4itemAdapt also struggle with it.
• Invest in a decent antenna if you are able. the better the equipment the more you will be able to get out of your setup.
• Plan your setup carefully prior to deployment. The preparation phase took way longer then the actual placement and connections of the antennas.
• Once you verified all is working properly then do the cleanup work like leading cables sealing of holes to the inside etc.
• Take your time and don’t rush, make sure all is functioning as expected in every step you take.
• Shoes for the head of the household can be expensive

All in all this was a lot of work but also it is very satisfying to see the improvements coming in.

[fhmiii]

This reminds me that I’ve been sitting on a project for nearly a year to improve my setup. I have LNA ready to install, but haven’t wanted to spend the time to take down my setup, install, and put everything back up. I want to do it when I can also move the whole thing from my back deck to a side yard, which will raise it about 6 feet and get it above neighbor’s roof and my chimney. I just have had other stuff I’ve needed to spend my time and resources on.

[mgrone]

These are plenty of antennas next to each other … i hope you told the antennas to not reflect any signal.

[tomvdhorst]

Yep they are behaving quite nicely next to each other, they only reflect on their sins so far , haven’t seen any adverse effects on that arrangement yet.

[mgrone]

You could also ask the higher VNA god about this. A prayer to one of the center antennas will tell you.

[tomvdhorst]

A VNA is still on the wishlist but it will probably land somewhere this year

[abcd567]

@mgrone

plenty of antennas next to each other … i hope you told the antennas to not reflect any signal.

My Samsung Mobile phone measures 70mm x 150mm x 20mm, and in this tiny space, it contains multiple internal antennas designed for 5G, 4G LTE, Wi-Fi, Bluetooth, and NFC connectivity
No issues at all.

• 5G Antennas: uses a 4-piece antenna set / module.
• NFC Antenna: Located in the middle/upper-middle rear of the phone.
• Wi-Fi/Bluetooth: Supports Wi-Fi 6 (802.11ax) and Bluetooth 5.0, utilizing internal MIMO antennas for Wi-Fi

 

[mgrone]

My yagi contains 4 elements which are all very close to each other in frequency. 3 of them are not even connected to anything.

[jimMerk2]

I am surprised that you are able to get away with having all those antennas outside on a railing. Isin’t there a HOA or somebody that has rules they want to enforce?

I would like to put up just one antenna outside on the roof, but hesitate because of HOA rules.

[geckoVN]

@abcd567

No issues at all.

But how do you know there are “no issues at all”?
What you know is that it works, but how much better could it be if the antennas were separated?
Wrapping your hand around the antennas (phone) and then holding it next to some wet meat and bone (your head) won’t improve it either. The fact phones work as well as they do, is quite remarkable.

[tomvdhorst]

Sure there is a HOA, I got permission from them prior to placing the antennas.

The requirement they had is that the antennas don’t stick out of the perimeter line. So they are allowed on the inside of the railing but not on the outside of it. The secretary of the HOA is a FM nerd so he knows antennas.

I’m on the technical advisory team for the HOA, whenever there are technical measures needed I’m getting consulted, for instance when a service provider wants to deploy fiber cabling. So being on a good footing with the HOA certainly helps in that regard

Since the antennas are recieving only they also don’t cause issues for the neighbours.

[jimMerk2]

I’m surprised they allow any antennas, just from the standpoint of appearance. They are pretty strict here, there are no antennas allowed except for those 1-ft TV satellite dishes.

To some extent, I can understand a blanket no antennas policy.
I can remember some ham radio antennas – 20 meter beams (1/2 wave 10 meters) that completely dwarfed the house. Course these ADS-B antennas are no where near that size and don’t really look that bad.