FlightAware Discussions

An Introductory Note About DIY Antennas

@wiedehopf

Thanks, never thought about that. I will check it, but before damaging it, i would rather try a DIY cantenna or something like that.

As i am close to EDDF (west of it) maybe that’s the reason why i am currently satisfied. Peak times show 100 aircrafts. What i do not get are aircrafts coming from east approaching, they are too low (or my antenna :stuck_out_tongue_winking_eye:)

Wow, saturday morning, many people woke up :slight_smile:

@geckoVN
Thanks for your input. Will try to improve. As stated, it’s a hobby and i like such challenges.

Forgotten to mention another funny fact:

If you look on the polar distribution where i got the most signal and the highest range is the opposite direction of the window where the antenna is located.

I would have expected that the view out of the window would be better than the opposite.
The antenna is “looking” towards EDDF and not westwards as the polar view looks like

Two of my receivers currently have an indoor antenna.

They are about 1km away from each other.

The yellow trace has a cut-to-length magnetic base antenna that came with a receiver dongle.

The red trace has a PCB dipole

It is quite a dramatic difference just replacing the mag base antenna.

It is a hobby for most of us. Welcome to the hobby.

It is also a global hobby. I am in Melbourne, Australia where is has just got dark on Saturday evening (1745 AEST, 0745 UTC).

The coverage map of all the Flightaware feeders is here.

S.

Sure, but i got up at 4am local time (due to our noisy neighbours) and not much traffic. Neither in the air, nor in the Forum.

Thanks for your suggestion. I’ve seen this antenna on eBay as well and i did not expect such a gain.
Will try it DIY first and then move to this one probably.

A quick spider is equivalent to the PCB antenna.
At least that’s my experience.

You can actually build a spider directly on the dongle if you want.
Similar to this antenna:
Three Easy DIY Antennas for Beginners

Yes, that’s what i thought about already
Maybe a project for a rainy day.

I just went up and move the antenna a bit. Even this gives a gain in signal and as a indirect effect longer range.

Looking forward for this DIY thing…

I was just running the small one liner from your wiki entry “optimizing gain” and it gives me this value:
"Percentage of strong messages: 7.804"

What do i do with this information now? any good or bad? What should i change from software perspective beside the antenna thing?
Or shall i start with the antenna first?

Advise on that is in the same post as the command.
If you have close by traffic that vanishes near you, reducing gain can help.
Right above the command is the link on how to change gain, does that link not work?

Changing the antenna you’ll have to have a look at gain again.

Yes, the advise is there, but maybe i have some issues understanding it, that’s why i was asking.

The close by traffic is stable and not vanishing, the trace is only interrupted the more far away the aircraft goes.

I think i leave this piece as it is and focus on the antenna first.

Thanks for your patient assistance with a noob having no idea what this is all about two days ago :slight_smile:

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Trial Run Results for Three Types of Whip Antennas

:flushed::flushed:

Impressive… I should check in the toolbox where to find a tong…

Meanwhile I changed the position slightly of the antenna without any additional stuff.
The range has been increased and also the number of flights and positions have been increased significantly. (from 1245/62430 to 1747/115288 in a few hours)

Now i will check cutting the antenna. I hope the lower part is long enough.

No need to cut the whip. Unscrew the whip, and use a thin wire cut to desired length as whip.

Oh, it’s that easy…

Will have to look for a thin copper wire somewhere in the house…

Is this a special tip at the end of the antenna?

It’s just to stop you stabbing yourself by mistake on the end.

I have used a thin steel tie wire.
image

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Alternatively, thin copper core wire of a scrap network cable can be used

image

image

I just found in my garage a piece of copper wire which is normally used for inhouse cabling (the fixed one), cut it in the appropriate length and wrapped it around the socket screw as mentioned above. This is just quick and dirty for testing:

The resuts are better than stock antenna:
aircrafts the same time: +10%-+30% (depending on the time of the day)
range: +20%
signal: +10%
message rate: +100%

So for me as beginner this is already an improvement, will test other antennas as well.
The antenna is currently placed on a kidney bean can, wondering if a cucumber can is getting better results. :slight_smile:

I made the changes yesterday late afternoon, so i can give an update after full 24 hours compared to the previous day.
So far it looks better. Yesterday morning at this time the # of aircrafts was 15, now it’s already 30 displayed in live view. You can see the antenna change in the graph at around 5pm

Did you place the antenna over a metallic plate or food can? That will bring significant improvement.

Yes, as stated it’s currently hosted by a kidney bean can i’ve stolen from the kitchen. My wife will hate me for this.

What i also have is a cookie box, will try it later
Does the diameter matter?

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Not much beyond 70mm dia. Please see this:

Trial Run Results for Four Sizes of Ground Planes

Similar to your result in Test Run 2 it doesn’t matter which diameter.

The bean can had approx 70mm, now the cookie box is more than 200mm… But the message rate is the same.

To me it looks like that the good indoor location matters more.
Tried to move the antenna a bit on the board and put a box under the can that it comes higher also had a (positive) impact to the results.

I will leave it in this position until the evening and compare it to the day before.