Yes, sure, here are the photos.
My installations are totally indoor, as I live in an apartment, and building management does not allow anything to be installed on roof or outer walls.
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I think my RTL-SDR LNA just died too. Long story short, having a new roof installed today and relocated the antenna assembly from outside to inside the attic a few weeks ago. Was routinely seeing targets 160-200 NM away with some even 200+ mile away:
Shortly after the roofers showed up, an hour later, I’m seeing my coverage cut in half:
Not sure if all the hammering did it in or if it was just it’s time. I bought it back in 2020. I’m a novice so I have no way to test, but I suspect it’s time to buy a new LNA from Uptronics.
Maybe the roofers shook something loose in your attic setup. Do you have any coax running close to the decking that they could have hit with a nail? I installed an Uptronics LNA and it died within 6 weeks time. Scrap metal.
Doesn’t look like it. I did check on it and nothing is visually different. I have the SMA and Coax connections sealed with self-sealing tape. None of the Coax runs near the decking of the roof. Perhaps I should go back up and check physical connections, but I did order a new LNA from Uptronics out of precaution.
A failed LNA normally behaves as an attenuator, i.e. it reduces signal instead of amplifying it. An easy test is to disconnect and remove LNA from your system and connect antenna coax directly to dongle (or to filter if one is already installed). If reception improves then LNA has died.
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I can definitely give this a try, but I am using a Bias Tee running power to the LNA. Would removing the LNA and still using the Bias Tee harm any other components?
After removing the LNA, the Bias Tee will start feeding DC to the antenna. If antenna has an internal short, the Bias Tee and possibly antenna may get damaged. Why not disconnect/remove Bias Tee also when you remove LNA?
If your dongle has built-in Bias Tee, then in this case there may be provision of turning-off dongle’s built-in Bias Tee.
The dongle is a Nooelec SmarTee with built in bias tee, and the ADS-B antenna is one from Vinnant. I am unsure if it possible to switch off the power to the bias tee or even how to if it is possible.
I do have a FA Pro Stick Plus I can swap out with the SmarTee if that helps.
This low cost Filtered LNA from Aliexpress is working 24/7 for last six months. Running just warm.
Not sure how long this one will last, the first one failed within two weeks, was running very hot.
1090MHz ADS-B Active SAW Filter & LNA 5V Power Supply
Price US $8
Shipping: US $2
I feed it 5V DC from a spare USB port of RPi using a short USB-A to USB-C cable.
Definitely more cost effective than the uptronics route I just went, but I don’t think I can run with this setup. RPi is located in a closet and connected to a 25 ft cable run to the LNA & antenna in the attic. I wouldn’t have a way to run power to the LNA from the Pi for that length of run, unless of course I can feed power to it via the bias tee.
Don’t you have enough adjustable gain in your base system and SDR to run without the LNA? I would think you would have your system gain throttled down in order to run the Uptronics and not overpower the receiver.
Just a novice here, but my original set up used Coax that was already inside the house which connected to an externally mounted antenna. I used these same discussion forums on whether or not this was possible. This was around 2020 and that thread is still around.
At the time, I was advised to utilize a SDR with a power injector/bias tee due to the length of the run of the coax, and also needed an LNA due to using the injector/bias tee. That set up ran well, but since the new roof was being put on, I had to find a new solution as I did not want the satellite dish mast the antenna was mounted to on the new roof. In this case, I just mounted the antenna in the attic and used the old equipment (LNA and SDR with bias tee) connected to a shorter cable run.
Overall, the new mount saw better performance until today when the roofer showed up, though I don’t know if the failure of the LNA and the roofer are related. In keeping with my current equipment, I thought it best to order a new LNA since the SDR bias tee still works.
I do plan to disconnect the LNA and swap the SDR bias tee with a FA Pro Stick plus and directly connect the coax to the antenna to see if performance improves. Since the Uptronics LNA has already been ordered, I’ll see if anything changes once I install the new LNA.
Lastly, not exactly shore on how to go about adjusting gain settings, or for that matter, even knowing which gain setting would be ideal.
What are the roofers actually doing?
Could it involve putting materials that attenuate RF on the roof?
I thought that might be a possibility, but the roofers simply came, removed the old shingles, added a plastic barrier, and then installed new shingles. I don’t think plastic would attenuate the signal so much that I’d have a 50% loss in traffic.
That plastic barrier may have some metal lining for insulation purposes. And that could make all the difference in reception.
Based on that data sheets, it doesn’t appear so:
“Comprised of two layers of nonwoven polyolfin sheets laminated together and coated with a polymer coating on one side.” No mention of metal in the laminations.
reading through their documentation, it’s based on polypropylen…
Here’s some “light reading” on the electromagnetic absorption efficiency of polypropylene
In summary, depending on the exact material and structure of that roofing material, it can have significant absorption in the relevant 1GHz range.
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It does say it is UV stabilised though. Nano ZnO (Zinc Oxide) is one of the common stabilisers.
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And I think the fact that your reception dropped might indicate that “something” in that plastic barrier is, indeed, a ‘barrier’
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I can’t be certain, but I think the drop in reception happened prior to the plastic being installed. The first hour the roofers were there, they spent it taking the old shingles off. I’ve got a new LNA on the way, but perhaps some trial and error may be needed, especially if I’m getting similar performance once the new LNA is installed.