The BIG and SMALL ANTENNA topic part 2

I am considering and asking these cases for minimal end-nodes, so the ground plane and colinear antennas are huge and bulky for these kind of nodes. What was your antenna’s gain when you got 1.7 km in urban environment? And what was your duty cycle? I mean, while you were getting data from 1.7 km what was the period of the incoming data? I tried with simple ir antenna which has a 2.14 dBi gain but did not got up to even 1 km in urban environment. Longest distance that i get with this antenna was approx. 800-900 meters. With standard copper wire -1/4 wavelength- antenna i got more efficiency which up to 1.1 km but it was not normal for Lora technology either i guess. Additional to this, my 5 seconds period was increased after i passed 800 meters and was not stable, i mean it increased to 25-30 seconds. What was your observations? Could you enlighten me?

what type of nodes you’re talking ? factory / DIY ? and what type of gateway

Its almost impossible to say whether you getting a range that is better or worse than expected.

‘Urban environents’ vary a great deal, in one 500m might be par, in another you might get 5km, all with the same basic setup.

The location, the height of the gateway antenna and the nodes, the proximetry of nearby objects will all affect the range, sometimes very significantly.

I would accuse the gateway more than the node. I do not know what do you mean for ir antenna, but normally the gateway location is the first determinant of coverage. A tracker I have with an antenna that could be 1/8 wavelength has been received up to 40km by a well placed gateway.

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110km with a Zane Ztube here in Wales UK… SF7

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Where can I find mounting brackets for my RAK antenna ? This is my antenna:

I found these brackets: https://www.123satelliet.nl/blueqon-WMM10-Muurbeugel-Zware-Uitvoering but these are oversized.

most brackets sold in dish shops are heavy duty
http://www.antennebeugel.nl/beugels.html

I look in auto accessory shops for exhaust pipe clamps. They have a range of clamp sizes to suit the wide range of pipes found on different make/model cars.

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quick%20antenna

Quick and dirty 868MHz antenna in 5 minutes

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I have 2 of these absolute junk super cheap fake nagoya 771 antennas in my junk box :sunglasses:

x1660
x1661
x1662

you think they can be ‘tuned’ … cut , to 868 ?

  • update - experiment failed :rofl:

x1663

I could have told you that before you cut it. These antennas are designed to be tuned to 2 frequencies and both sections are dependant on each other.
For example: one antenna is tuned for 144 MHz and then electically sized as a 1/4 lambda antenna. at the same time it is tuned for 430 MHz and electically sized as 5/8 lambda antenna.
What happens is you cut it somewhere to change resonance? you will have to cut is twice to stay resonent in the way you want. It will not respnd as you hope. You know now :grimacing::grimacing::grimacing:

yes I did … the fr center indeed changed, but just a bit to 220 Mhz … lesson learned , 1.80 wasted :innocent:

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I found this one:

€ 6,99 | OSHINVOY Outdoor patch antena installatie L beugels Antenne fixatie holding pole U bouten beugel
https://s.click.aliexpress.com/e/s5YXAxlQ

May is this some thing for you, only use the brackets.

Hello @gaguilar,
i really appreciated your question concerning the size of the wires and copper part in the antenna. Did you manage to understand why they call this 868Mhz tuned while it seems to be a wrong size ?
thanks for your insights

I stumbled over this simple mount for RAK antennas. Not for outdoor! Would be great if this should be available in a material that is resistant for outdoor use.

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What do RF-engineers do when they are in self-chosen isolation: They measure antennas!
These antennas I purchased for experiments and specific projects

868 MHz dipole

image


The antenna is good for 868 MHz with > 17 dB return loss.
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868 MHz logper

I purchased this antenna to connect to a node that has poor coverage at the edge of the TTN coverage of our town. 19 Dollar is a good price for a logper. The downside is that I have to reduce power from the node to meet regulator constraints.

image
At 868 MHz a return loss is delivered of 20 dB (very good!) The two dips are caused by the different length of the elements of teh dipole.
image
This antenna is painted for cloaking purposes.

434 MHz antenna

This antenna I purchased for an experiment (Not LoRaWAN).

image
Although this advert is no langer available, equivalent types can be found.

The antenna perfoms OK with > 11 dB Return loss.
image

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Does anyone has design for 868MHz PCB antenna or know where to buy some that can be useful? I’m looking something that I can use inside of enclosure, possible some tracker. Thanks :smiley:

Try a Google search on;

texas instruments 868mhz pcb antenna

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Hi @slaven96,

I use Molex 105262 and Taoglas PC81.07.0100A.db. Both are really good as products that can be purchased online.

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