ADS-B antenna in attic?

[kc2klc]

I've been using a roof-mounted VHF/UHF discone for ADS-B reception with moderate results. I decided to purchase this dedicated ADS-B antenna (at under $30 who could resist?): 1090MHZ 36DB SMA Active ADS-B PCB Antenna with Biaser Tee Kit
The antenna element is a circuit board that appears to be this one: ADS-B 1090MHZ Gain 2.0dBi Antenna Receiving Aerial Aeronautic Facility Spare Parts for DIY Self-Made Expreiment

It has a (purportedly) 36 dB preamp built-in. Despite that, I think I should keep the coax length as short as possible to avoid loss. I'm wondering if I can put this in my attic? The roof consists of thin (probably about 3/8" / 9.5 mm) particle board overlaid with standard asphalt roofing shingles. It wouldn't be near any plumbing, wiring, gutters, or other metal infrastructure. Is there any chance that the roofing materials, which I would assume are non-conductive, would substantially attenuate the 1090 MHz signals? Are there other concerns I should have?

Thanks for any advice on this!

 

[MDScanFan]

In the attic should work okay but why are considering putting it the attic versus putting it outside like your discone? Mounting it outside in the clear will only improve performance.

With the preamp after the antenna the coax length is basically inconsequential provided you are using something halfway decent.

Also, that is a lot of preamp gain. You may need to add some attenuation between the amp and receiver to prevent overload.

 

[Ravenfalls]

This is with 1090Mhz antenna inside, it does very well. Plan put antenna outside once the weather is cooler.

 

[popnokick]

Mine is in my attic... same antenna. Works very well.

 

[dmchalmers]

I guess this is the stupid question of the forum but how does this work? only for computer or does the work with a scanner? Sorry if this is a stupid question.

 

[devicelab]

It needs to be outside. Seems rather pointless to go through the setup and burn all that money on something that gives only a fraction of the performance.

 

[vagrant]

I guess this is the stupid question of the forum but how does this work? only for computer or does the work with a scanner? Sorry if this is a stupid question.

Basically, a computer of some type is needed as well as an antenna, coax and ADS-B receiver. The receiver could be an expensive one, or a $25 USB dongle.

At one location I use Windows 10, ADS-B software, a USB dongle and an antenna. It is indoors and the range sucks, but it is across the street from an airport. It only gets about 10 miles because of the building it is in and the lower gain antenna.

Another location uses a DPD Productions outdoor ADS-B antenna around 30' AGL, a preamp/filter combo inline on the coax, and then a splitter that feeds an older ADS-B receiver to a Windows computer running software that feeds it to a service. The splitter also feeds a $25 USB dongle connected to a Raspberry Pi computer that is running a custom software image that feeds a separate service.

If your scanner is able to dial up the frequency and you have an antenna tuned for 1090 MHz, you probably would not notice/discern/hear the ADS-B signal when transmitted. If you connected that antenna to an SDR, you may see the quick blips on the waterfall.

 

[dmchalmers]

thank you i'll look into this more.

 

[kc2klc]

Thanks for the replies - especially appreciate the concern raised by MDScanFan regarding being careful with the massive (again, supposed - seems a bit inconceivably high - but I have the equipment to test this). Not sure why people question my desire to mount it indoors; in fact, I have several reasons, including the concern my wife has with the number of antennas appearing above our house :O And as far as "burning money", well, I already had the SDR and computer - all I spent was about $20 on the antenna (I had some credit with BangGood). I am encouraged by PopNoKick's report and Ravendalls' results (thanks for posting those!), so I will give the attic mount a try.

 

[popnokick]

I need to qualify my attic mounted ADS-B antenna: it is the same circuit-board type antenna from eBay BUT it is hanging in an attic window. At 1090mHz conventional untinted window glass is not an issue. However not having the antenna in a window is likely to attenuate the signal.

 

[Ubbe]

It has a (purportedly) 36 dB preamp built-in. Despite that, I think I should keep the coax length as short as possible to avoid loss.

It seems to have a 1090MHz SAW filter and then you can run a very high gain without any overload problems. I set my RTL-SDR to full auto gain and it improved reception compared to any lower gain settings when I have a 1090 filter and a 15dB LNA using a 6dBi roof antenna. It's pretty much impossible to have one amplifier doing a 36dB gain, that's an amplification of 4000 times. Either it's two 18dB amplifiers in series or it's actually a much lower gain figure. But coax length shouldn't be an issue if you use something better than RG58, like RG6.

/Ubbe

 

[msingewald]

Unless you are in an area where there aren't many other receivers, what is the point of needing more than 150 mile range? I understand redundancy is good, but looking at the receiver maps, most areas have tons of redundancy.

 

[ArtU]

Unless you are in an area where there aren't many other receivers, what is the point of needing more than 150 mile range? I understand redundancy is good, but looking at the receiver maps, most areas have tons of redundancy.

For when the internet and cell phones are down, you want to see where the planes are , or are not?

 

[msingewald]

For when the internet and cell phones are down, you want to see where the planes are , or are not?

That is certainly a valid reason.

 

[popnokick]

Will all of the different flavors of ADS-B receivers (FlightAware, etc) work WITHOUT an Internet connection? I thought the Internet connection was used for mapping & ID support.

 

[dlwtrunked]

Unless you are in an area where there aren't many other receivers, what is the point of needing more than 150 mile range? I understand redundancy is good, but looking at the receiver maps, most areas have tons of redundancy.

When in the middle of no where without Internet or cell phone, it is needed. I live halfway between DC and Richmond VA and when I go into the mountains, that is often the case. Also, I use adsbscope for getting the maps and figured out how to add my own point to them like my house and local small airports. Although written for other hardware, it works fine with USB SDR dongles when properly set up.

 

[Ubbe]

Main reason for me are that police and mil are censored on most sites and you'll need your own receiver to pick those up.

/Ubbe