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For mag-mount version, yes, (click here), but it is not a true comparison due to substantial hardware difference. Anyway it is better than no comparison.
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For quick spider version, no, but plan to do it when find time. Will post when done.
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Hi @foxhunter
Regarding the 1.2m fibreglass antenna ADS-B 1090 MHz Antenna (1.2m, 8.5dBi) - Pimoroni
I purchased one from Pimoroni back in January and it has exceeded my expectations, since I was dubious about the gain claimed. After a short period testing in my loft I judged it was robust & weatherproof enough to go outside, so I got it moved up to the top of a pole on my chimney stack, with a massive improvement.
I feed the signal to an LNA in my loft via about 5 metres of Ecoflex 10.
I’ve just managed to break into the Top 300, so it can’t be that bad!
I notice the price has risen £8.30 in the meantime, so I guess it is a popular product 
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Can you please be a bit more detailed? How did you measure that improvement? Ranking alone is not a good indicator
What’s the improvent of these values
- Range
- Positions reported
- Aircraft reported
Would be interesting to see compared to your previous solution (whatever you used before)
Hi @foxhunter
I’m not trying to be evasive, it’s just I don’t have the figures for you.
All I can say for sure is: a) it’s better than the £5 magnetic “toy” 20cm tall antenna I initially used with my system b) using the Pimoroni in my loft improved the range and c) moving it to an external position and higher gave me my current system, which performs very well with large numbers of positions and range around 250 nm.
So sorry, I can’t really compare A to B or give any quantitative results or measurements of actual gain.
Since March I saw a steady fall off in positions and aircraft reported (just like everyone else) but it is beginning to pick up again and my message rates are higher than I’ve seen before (but I only started watching in January).
I think if there was anything fundamentally suspect about the antenna the graphs would have highlighted the issue right away. But this picture looks good to me:
No worries, i get your point. It was a chance to ask for.
Yes, the traffic is increasing here as well. the times with # of aircraft at the same time is more often > 100 since the downtrend in March.
I have both the DPD 1090 and FA 1090 antennas. Indoors on my backup/test Pi and receiver, the DPD performs a little better. Outdoors up on the mast 30’ feet up, they both perform the same based on my tests. Stating the obvious, the DPD antenna is much longer and heavier so the FA antenna requires less substantial mounting and mast effort.
Due to size and color the FA antenna doesn’t stand out nearly as much either if you need to avoid attracting a lot of attention. I painted the DPD which helps but it’s a pretty wide piece of equipment that stands out anyway.
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Thanks. That is what i expected.
Well you need an environment to use the extra gain.
That likely means a pretty good view on the radio horizon or possibly near the sea to take advantage of weak ducting phenomena.
If you are in Europe, you’d also want an LNA / airspy combined with the antenna, because with an FA Pro+ you might be basically saturated at 2000 messages / s or so.
If you are heavily terrain constrained, the DPD won’t have any benefit.
(and with heavily terrain constrained i mean 150 to 200 nmi limit according to heywhatsthat.com)
(GitHub - wiedehopf/tar1090: Provides an improved webinterface for use with ADS-B decoders readsb / dump1090-fa)
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correct, that’s why my test with the AirSquitter did not deliver much better results.
From what i’ve read somewhere here earlier the limitation of the blue stick based on the chip is somewhat at 1300, that’s what i saw last summer as peak.
The AirSquitter performed a bit better. While the Raspberry with blue stick achieved 1100 msgs on my days of testing, the Squitter went up to 1400 msgs.
Finally the amount of aircraft and position reported to FA were pretty much the same.
I also checked OpenSky-Network which delivers the messages per day as well in the profile. While i have approx 45 Million Messages, the day with the Squitter delivered a little above 50 Million on that day.
That’s why i came to the conclusion that a check of the max range should be mandatory while trying to improve something.
No idea if an Airspy-Filter-LNA combination will improve something, but i’m done for the moment with testing expensive equipment
Just to join the conversation - Today is exactly one month since my antennas went on the roof… The inner-plot is the Jetvision/FA Antenna. Outer-plot is the Airnav one.
Same plot is seen on ie. Radarbox. My stats on FA shows a few lesser planes a day/messages a day to.
Don’t know why the difference seems to be more significant towards W? N/S is almost the same range.
Might try the linked antenna some day.
I wouldn’t expect it to perform better than the Airsquitter (if the airsquitter has a sufficient high gain antenna … otherwise it might be improved by using an LNA as well, not sure exactly)
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Trees in that direction?
Why would one antenna work better in that case?
I did mean the difference in distance they’re covering - Not why i’m “deaf” to NW. Look at the plot, one antenna goes 50 nmi further then the other. N and S is almost the same range.
Trees are an attenuation, say a weaker signal from that direction.
The horizon or mountains on the other hand are a hard block, that basically eliminate the signal.
Both antennas are capable of looking to the horizon “through the air”.
But when for example trees are in the way, their different performances shows.
Anyhow you’d probably need to swap over the receiver or specify the coax you use for the FA antenna.
You could also have the FA antenna mounted crooked / not vertical in the east - west direction.
That would explain good range north - south, worse range east - west because the disk of highest gain isn’t aimed at the horizon.
The antenna is installed like the picture below shows (sorry for quality)… Jetvision on the left, which actually are W… Airnav on right.
Wouldn’t a bad coax influence the N/S direction as well? Makes no sense to me. Anyway, i use the supplied cable from Jetvision, print on it says R:F 100 Low loss 50 ohm…
The bottom part of the antenna is the most important, if the base doesn’t overlook the roof that would reduce performance in that direction.
On a photo it’s really hard to tell if something is crooked 
Which receivers are you using with each?
Can you switch them to see if if the antenna or the receiver makes the difference?
They’re almost their full length above the roof - The roof are pointing north, seeing it from the antennas view. The base can’t see north, but the range is OK.
Recievers are the same. Antenna > Uputronics LNA > Blue Flightstick > Pi. (Same behaviour with the green Airnav-stick, and exact same range overall)…
If i swap the antenna cables at the LNA, the result are exact the same, just mirrored of course.
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I have used ranking as my fine tuning indicator. The problem is it takes a long time to evaluate a change — 30 days of data seem to be a good sample interval.
Another relative measure (in the USA) comes from comparing parallel 1090 and 978 systems. For a given altitude window if the 1090 system is reliably tracking at ranges as great as the 978 system in the much more dense Mode S signal environment that’s an indication the 1090 receiver is coping well.
My mode S processor sees (or saw in pre-CoVid days) a peak of about 2,000 messages per second and the 978 peaked at about 1% of that.
I am using already the Jetvision antenna, next step would be the active one from Jetvision, pretty expensive, but even then no guarantee for an improvement
I also have no idea if an additional LNA would give better results. I should have opened the case to see if an LNA is on-board, but i would expect so.
I returned the Air!Squitter now as it’s for me to expensive for almost no change, except having a nice case and OLED display
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You would more than likely have better results if you could get that LNA mounted at the base of the antenna - unfortunately due to crappy design on the AirNav unit, that would be impossible, but would be curious to see a 24 hour test with it that way on the Jetvision side. I would also suspect your gain is probably down in the 20-s somewhere with all that amplification?