Another antenna issue

The little mobile antenna in the last pic (beer for scale) came with the PiAware kit. Using the BBQ grill as a ground plane and sitting a mere 3 feet off the ground, it gets over double the message rate and range as the new antenna tuned to 1090 that I installed at the roof line this weekend.

I confirmed that the new antenna worked better than the old one before I mounted it. Before I climb up there again I’m interested in hearing from others. Is the issue that the antenna is touching the overhanging shingles, or that not enough of it is actually above the roof line, or some combination of the two, or something else entirely?



Is that a crimped connector?
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If so, it isn’t weather proof, so wouldn’t last long.
Also, if the crimp isn’t very tight, it can easily slip off causing an open or intermittent connection.

Ideally the active part of the antenna should be above local objects, so it’d be better if you can raise it above the ridge line, but I don’t think that is your major problem.

This is the antenna w/ cable that I purchased. https://www.amazon.com/gp/aw/d/B09BQ4H26L?psc=1&ref=ppx_pop_mob_b_asin_title

I intended it to be a solution for the summer while I worked on a longer term antenna mast strategy so durability wasn’t my main concern. And it worked a lot better while it was propped up on my ladder awaiting installation. It’s quite possible the connection came loose as you suggest, although I didn’t subject it to any abuse during installation.

If the small one performs better then the one on the roof, there seem to be a different issue.

As @geckoVN already suggested it can be an issue with connectors.
But also cable and the proper gain setting. If gain is too high, the “noise” can also reduce the performance.
If cable isn’t made of good quality, the attenuation can be high…

Pretty hard to itentify the issue from far away
I don’t think the roof itself is causing it, even if the antenna is not 100% straight into the sky

I can see two things from that ad.
The first is that the coax they supply is a very poor choice for microwave frequencies. It should work over only 10 ft, but you’ll be loosing a lot of the benefit of an outdoor antenna
image

Second is the connector. The connector on the (bottom end) cable is an RP-SMA that does not have the centre pin. Did you use the adapter supplied, as you’ll need it to turn it back to standard SMA.
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I think you may have hit on the cause here. I didn’t notice that and I didn’t use the adapter. Now I’m surprised that it receives anything at all. I’ll post a followup once I find and install the adapter. Thanks!

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Damn. It turns out the pics on Amazon are wrong. The cable does have a regular SMA connector and the adapter converts it to RP-SMA.

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Hi,

Looking at the photos, it looks like that might be metal drip edge under the shingles bent at a 90 degree angle down. Even more of that metal is under the shingles. That much metal only an inch or so away from the antenna probably is not helping. If testing lower gain settings does not help, it might be worth trying a simple wood offset mount to get the antenna just slightly above the metal drip edge.

Once you get it working, you will probably want to secure the coax from moving. The wind blowing it the way it is hanging from the connector will probably cause stress to the connection.

Good luck,
-Dan

It was looking good for moment there

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