Cool, thank you Nick!
So no groundplane. I will have to make something which improves my vibration issues. I guess I will try something like moongel.
I am guessing the design will help people like @Luke_Wijnberg in a banking situation. Would be cool to see some comparison.
Anybody got some intel about this?
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Tallysman single frequency = 105 $
https://www.digikey.com/product-detail/en/tallysman-wireless-inc/33-HC771-28/1526-33-HC771-28-ND/10473742
Tallysmann multi frequency = 274 $
https://www.digikey.com/product-detail/en/tallysman-wireless-inc/33-HC975-35/1526-33-HC975-35-ND/10473744
Looks like the helix antenna can be used with or without ground plane.
Helix antennas can be designed for use with or
without ground plane. If a helix antenna is
designed without ground plane it can be tuned
into such to show a more omni-directional
radiation pattern as shown in Figure 22.
Although we can determine an axial ratio close to
9 dB between zero degree and 90 degrees
elevation, which compares to the patch antenna,
the back lobe of the helix generally degrades
much smoother and does not show any
sensitivity at the –180 degree direction. In
contrast, the back lobe of a patch antenna
depends very much on the size and shape of the
ground plane.
Yes, thank you. I think groundplane is the wrong term, these groundplanes we use are RF noise shields I guess.
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No, no groundplane anymore.
The antenna vibration is supposed to be mitigated by the antenna mast being pressed into a 3mm piece of sorbothane stuck to the side of the P4. It is the material that kept coming up when i was searching for ‘best shock absorbing material’
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Sorry to ruin the party but aren`t you introducing a flexed vibration ( like a tuning fork) ? Or you might have solved it some how, but hard to tell from the picture
Edit: Your wooden pole might be stiff enough to counteract that, of course
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When the ‘sleigh’ is fixed to the P4 the mast is very softly pressed into the sorbothane® patch. The mast should have a minimal amount of static flexion, and the mast should not separate from the sorbothane® patch during flight. My hypothesis is that this damping arrangement should intercept and reduce some of the whipping motion of the antenna mast and discourage any resonant vibrations that may have occured in the absence of the patch.
Does it do this? I don’t know.
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The best way to search it at Ali:
BT-560D for L1 solution;
BT-560 for L1/L2 solution.
The price is about 50 usd.
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The result of this survey (compared against a Leica GS18 T) is 0 to 2 cm deviation on concrete and bare ground areas.
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HI,
mine finally (after only! 15 days, quite good I think) arrived.
Short test on the ground makes me hope that the new one (left) is at least not DOA. I.e. I have big hopes and I’m very happy about @VanavaraDigital and @wsurvey help to choose the antenna.
Hi Tobias,
Those SNR look quite acceptable, but where’s the rest of your BeiDou satellites??
Also It would be negligent of you not to revisit Glonass tracking with your new helical antenna for some tests. GPS+GLO+GAL v GPS+GAL+BDS. Though in your part of the word BeiDou availability looks better than Glonass. At least it should be!
Hi Nick,
I think the rest of the sats are missing because I was between high trees and houses.
I’m quite happy with Beidou (at least until yesterday since it seems that there is a bug in ReachView which might be connected to Beidou???).
If I have the time to test against each other I will do - but GPS-GAL-BDS is great. If I can improve with the new antenna a little bit I’m more than satisfied, I think then I have to focus on other things (vibration, image quality and processing parameters) to improve the result.
I have a new mounting for the antenna which includes Kyosho Z8006 Zeal and shortening of my antenna boom. I hope to reduce my cycle slip issues (when I compare a windy and a calm day it is still like day and night). I will report… .
Congratulations!
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