@gtj0
Your flow chart says something like this:
if (it aint broke){dont fix it}
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More of a question of how sensitive things are, I wasnāt sure if the impedance difference was noticeable at that level.
Awww! But if I donāt fix(break) it I donāt learn anything 
Which is part of the fun of the experimentation.
Better yet, it seems that tuning hasnāt helped in all situations. I believe Iām getting more overall reports/day, but max range isnāt quite as far. Still data gathering.
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What are the dimensions of you V stub after tuning?
- Length of upper wire
- Opening of V
- Length of lower wire
- Length of radials
- Number of radials
If you want to experiment, start trimming-measuring ritual with radials cut by 5mm each time till it becomes 30mm from edge of SO239.
At the ed of experiment you will have to discard the over trimmed radials and make new radials of optimum size
Do not expect that the V-Stub will out perform the FA antenna. My trial runs show it is about
- Plane count: 75% of FA antenna
- Message rate: about same as FA antenna
- Maximum range: in some directions about same, and some directions slightly less than FA antenna.
However results were noticeably better than a Spider.
I can say (as indicative figures)
- FA antenna 100%
- V-Stub 70% ~ 80%
- Spider 60%
The V-Stub is dimensions I have are:
short end: 84mm
v width: 45mm
long end: 143mm
8 radials which are soldered to a 25mm copper washer, distance from the center of the whip to the end of the radial is 72mm
the copper washer attached to a F-type coax connector. All wires are from 12ga copper (2mm diameter)
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Neat build 
Well done 
If the message count is about the same and the range is about the same where are the planes that are not counted hiding?
Are they close in planes that never appear?
If you consider the deviation from the vertical may be providing a small bit of loading and the fact that the total height is just under a full wavelength long is it possible that this is behaving as a full wave radiator with the impedance being matched by fiddling with the length and/or position of the radials?
As opposed to a colinear antenna made up of a Ī»/4 and a Ī»/2 fed through a 180Ā° phase shift?
Just trying to understand how this antenna is functioning.
Yes, the well known standard is as you have described (Ī»/2 over Ī»/4). One design with such a configuration was shown in my March 2016 post quoted below:
EDIT:
The above image is large, and system reduced itās size to the point that it bacame difficult to read. I have now split this drawing into 3 parts to reduce size, and posting these below:
Very nice!! You may actually find that 4 radials work better than 8. That was my experience anyway.
Enlarged View of V-Stub Quick Spider made of RG-6 coax only - No connectors.
On top, the small sliding piece of wire (with core insulation to hold the sliding wire in place) is for conveniently adjusting the length of top wire for best MESSAGE RATE (if no swr meter is available) or minimum swr if swr meter is available.
Ā
Ā
Ā
Ā
Pigtail required to connect RG-6 coax to FA Pro Stick
30 / 50 / 60 cm, F-female to SMA-male pigtail RG316 / RG58 / RG174
Ā
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Hi!
Does RG-6 cable need to contain copper?
I have https://www.biltema.fi/toimistoātekniikka/tv-tarvikkeet/antennit/antennikaapelit/antennikaapeli-rg-6u-2000044708, but this one apparently has nickel plating? Does it somehow affect the performance of the antenna?
As long as it is a conductive metal, it will work as an antenna or shielding. Aluminum is used in antennas more than copper. Nickle will be fine.
RG-6 is 75 ohm nominally, and a slight mismatch for the 50 ohm impedance of most dongles. It will still work. Recommend you keep the cable length as short as reasonable as RG-6 does attenuate signals at ADSB/1090 MHz.
Have fun with this hobby. Experiment, move the antenna around a bit to find your best location. Antennas are sensitive to surrounding objects and a couple of inches can change your results significantly.
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RGxx does not give a full specification of the cable. It is best thought of as a set of dimensions - so RG6 will fit an RG6 connector, but not (say) RG59 connectors.
RG6 commonly uses a copper plated steel centre conductor.
The braid may be aluminium, Al clad steel, copper, copper clad aluminium etc. and then there is the foil.
Similarly, RG6 may have 2, 3 or four shield layers depending on the application. Naturally, the price is range is wide depending on the product you select.
For good performance, Cable TV or Satellite cable should be chosen.
Quality is very much reflected by price.
I was thinking that I would buy better cable + adapter cable. I was thinking to buy this adapter: Adapter, SMA female - MMCX male, RG-316, 10cm
And this RG-6 cable: Antennikaapeli RG-6, 120 dB, 7,5 mm, valkoinen (metrihinta)
(There are also other options here if someone can recommend some better cable: satshop fi/catalogsearch/result/?q=RG-6&product_list_order=price )
I have few questions about those RG-6 cables:
Is a thicker wire better for making the antenna?
Is it better to have higher or lower shielding Immunity (dB).
Thanks for the help, Iām new to this stuff 