The BIG and SMALL ANTENNA topic part 1

Thank you very much for the answer… but sorry that didn’t make any sense to me, and google seems to fail helping me there.
May I ask you - or anyone who knows - to provide some link or pointer about this ?

GTem cel: https://en.wikipedia.org/wiki/GTEM_cell
OAT: http://www.compliance-club.com/archive/old_archive/020312.htm

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Just wondering because this topic’s title casing and the images in the first post seem to contradict:
Is this the “BIG ANTENNA” topic or is this the BIG “ANTENNA topic” ? :blush:

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the idea is everything about LoRa antennas … BIG and small :sunglasses:

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Getting 7.5km using the manufacturer provided long-duck antenna with a Laird RG168 gateway.
image
Anybody know what can we expect if we install something more like this?
http://www.webb.co.za/storage/files/WEBB_PROX_ANTENNA.pdf

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My Procom CXL900-868 arrived.

IMG_20171214_185642

It’s bigger than expected :open_mouth: .

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Said the actress to the bishop :wink:

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VERY GOOD! THAT is a good quality antenna. :clap::clap:

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MAX. POWER 100 W so no problem :wink:

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Interesting article on building and using cantennas (directional).

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anyone tried or heard about this one?
http://www.delock.de/produkte/H/89583/merkmale.html

it’s in the 30€ range around here, guess i gotta give it a try for my TTN gateway…

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looks fine to me :sunglasses:

We just inspected the “Antenna collinear 868 Mhz 869 mhz LORAWAN LORA great gain SDR USB smart grid” from https://www.ebay.com/itm/302598573188

Interior:

afbeelding

Bottom coil:

afbeelding

Top coil

afbeelding

Measurements will follow.

I have seen a discussion before about the collineair DiY antenna :flushed: from @lex_ph2lb

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Look forward to your results as I was just about to order one, will hold off for now

I am having good results at the moment with the DIY 1/4 wave GPA.
Would it be possible to compare your measurements to this one?

We are considering antenna gain measurements at the moment.
The idea was proposed earlier on this forum.

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Is it not possible to come up with a top ten list of antennas for under 100 euros , we seem to never pin this down to which is the best for lorawan and in what order

How about using one popular antenna as the baseline?

Hi @paulb, the IEEE norm is to use a 1/2 wave centre-fed straight dipole as a baseline antenna for RF testing in UHF. This is also the most common external antenna. Antenna gain is normalised at 2.15dBi in the perpendicular axis. For EU 868mHz each side of the dipole is 1/4 wave or about 8.5cm so typical length is about 18cm.
The transmission line is also very important and any serious comparison needs to standardise the type and length of coax used, e.g. RG58, 2m long.

Here are the measurements of the antenna I have presented the interior of:

afbeelding

afbeelding

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