We are setting up several Lora stations on farms, to go with our agricultural sensors. What would you say is the best option for fixing to the side of a bar?
For the moment we ordered 12 dBi Taoglas Braccuda, and hope to range-test it next week.
Also I’ve done some casual testing (without ttn mapper) in city and got about 900 meter range
You are aware that to be legal you need to keep the ERP to 14dBm ?
If you use a standard gateway\node setup, which defaults to a TX power of 14dBm, that antenna would increase ERP to 24dBm…
In practice (with most TTN applications) the only legal use of a gain antenna is to offset connector and cable losses.
HI @ClumsyPilot, the following is the mechanical drawing of the Taoglas OMB.868.B12F21 antenna.
I use a lot of the 5dBi equivalent of the 12dBi antenna that you have ordered. Per the mechanical drawings, I always fix them to standard 2inch/50mm telecom masts using the u-bolts that are delivered with the antenna.
You ask about attaching to the side of a “bar”. Do you mean “barn”? If so then don’t attach the antenna direct to the side of the barn, you need the entire antenna to stick up clear of the apex of the roof.
Are you aware that the 12dBi antenna is 2.4m long? You will need to use a substantial mast - like a scaffolding pole. The scaffolding pole is normally attached to the side of the building using standard heavy-duty telecom “T & K” brackets.
Following is a picture of LoRaWAN base-station using a Taoglas 5dBi (1m long) antenna mounted on a barn using T&K brackets, unistrut and a scaffolding pole. Your antenna is 2x the length of this antenna.
Depending on your ant height & assuming you GW location is near Icentrum north of Aston Uni you are doing well to get signal west to where shown on the map beyond the Children’s hospital. Can I suggest you do a slow driving test n/ne along the A38 Aston Expressway towards/beyond the M6 intersection. You should be getting good coverage 300-400m all around you but then extending much further in the N/E quadrant. You should hold signal to the motorway, possibly loosing some from around Aston Park and across the River Tame valley picking up again as you close on the motorway intersection. Beyond the M6 if you continue and do some war driving around Gravely Hill area you should see coverage around there 
you may also see signal along Victoria road between A38 & A34 and again west A34 towards Lozells on the B4144 or B4145. If you can demonstrate that then you know don’t have a setup range problem but rather a topography & building clutter problem 
No need for exotic ant in that area as this should be achievable with a typical As Supplied GW ant e.g. A 2dbi ‘rubber duck’. Should be ok for anything SF9-SF12. Only need greater sensitivity if trying to use lower SF’s for shorter on air time. Suggest you try same ‘drives’ (walks!?) with nodes @ different SF’s or repeat runs to compare and assess and with low duty cycle to avoid breaching regs…hence slow to get good geographic coverage without Tx gaps
yagi antenna GSM outdoor 9 units 13DBi 824-960mhz 900 mhz GSM CDMA (now € 10,66 incl. ! )
usable ? yes, perfect for a long range ‘field’ sensor node imho
I also tested these 11 DBi versions… they are very BAD
It is a little bit of pity that you did not mount the antenna’s in free air. Lying on the floor/table definitly influences the VSWR and frequency-response.
true and I did hold it on the cable when measuring, and put it on the (concrete/iron!) floor LATER and took the picture 
It looks good, so I ordered one.
Hi all! I am building a Pi-based RAK2245 gateway and I already have 1090Mhz 26 inch 5.5dBi ADS-B antenna mounted on the roof, which I would like to re-purpose and use it for this gateway; at least temporarily. I know it’s not ideal for the US-based 915Mhz, but will it work decently for now, or should I just bite the bullet and buy a new one?
Thanks guys!
Jason
byte the bullet imho and buy a tuned antenna for 915…
If the off frequency antenna is a poor match at a frequency it was not designed for, there is the possibility you could damage the gateway.
Do you feel lucky ?
Has anyone been able to conduct antenna gain tests on the RF Solutions 3dB SMA antenna?
We’ve used many of these with good success, but I’m doubtful of the 3dB claim, since that’s a hard value to manufacture to, especially at the price point.
What I can’t find in the specs is the SWR of this (possibly china made) antenna… did you measure that ?
Haven’t been able to thus far. You’re correct, the specs are minimal. I have the original RoHS certificate but that obviously contains no info about antenna params.
I can’t name the brand/source, last couple of years I ‘collected’ many of these.
But I can tell you that the ones with a length of 210 mm gave me the best results
So that’s probably the one you use
Yes, mine measure ~210mm too. I believe they all come from the same factory anyway! They’re great antennas, but I doubt the 3dB gain quoted is true. We’re actually running some tests at the moment and trying to squeeze as much out of the unit as possible, but have to assume antenna gain in our tests as we don’t have the equipment to test it inhouse. Something around 2.2dB would actually be ideal!
I had also one that was likely a 2.4GHz antenna sold as 868, indistinguishable from outside. The I found a couple of sources for the right ones.
In my informal trials, however, they do not seem better than a GPA.
